first commit

wp-content/plugins/wp-scss/scssphp/LICENSE.md

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+Copyright (c) 2015 Leaf Corcoran, http://scssphp.github.io/scssphp
+ 
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+ 
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+ 
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

wp-content/plugins/wp-scss/scssphp/README.md

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+# scssphp
+### <https://scssphp.github.io/scssphp>
+
+![Build](https://github.com/scssphp/scssphp/workflows/CI/badge.svg)
+[![License](https://poser.pugx.org/scssphp/scssphp/license)](https://packagist.org/packages/scssphp/scssphp)
+
+`scssphp` is a compiler for SCSS written in PHP.
+
+Checkout the homepage, <https://scssphp.github.io/scssphp>, for directions on how to use.
+
+## Running Tests
+
+`scssphp` uses [PHPUnit](https://github.com/sebastianbergmann/phpunit) for testing.
+
+Run the following command from the root directory to run every test:
+
+    vendor/bin/phpunit tests
+
+There are several tests in the `tests/` directory:
+
+* `ApiTest.php` contains various unit tests that test the PHP interface.
+* `ExceptionTest.php` contains unit tests that test for exceptions thrown by the parser and compiler.
+* `FailingTest.php` contains tests reported in Github issues that demonstrate compatibility bugs.
+* `InputTest.php` compiles every `.scss` file in the `tests/inputs` directory
+  then compares to the respective `.css` file in the `tests/outputs` directory.
+* `SassSpecTest.php` extracts tests from the `sass/sass-spec` repository.
+
+When changing any of the tests in `tests/inputs`, the tests will most likely
+fail because the output has changed. Once you verify that the output is correct
+you can run the following command to rebuild all the tests:
+
+    BUILD=1 vendor/bin/phpunit tests
+
+This will compile all the tests, and save results into `tests/outputs`. It also
+updates the list of excluded specs from sass-spec.
+
+To enable the full `sass-spec` compatibility tests:
+
+    TEST_SASS_SPEC=1 vendor/bin/phpunit tests
+
+## Coding Standard
+
+`scssphp` source conforms to [PSR12](https://www.php-fig.org/psr/psr-12/).
+
+Run the following command from the root directory to check the code for "sniffs".
+
+    vendor/bin/phpcs --standard=PSR12 --extensions=php bin src tests *.php
+
+## Static Analysis
+
+`scssphp` uses [phpstan](https://phpstan.org/) for static analysis.
+
+Run the following command from the root directory to analyse the codebase:
+
+    make phpstan
+
+As most of the codebase is composed of legacy code which cannot be type-checked
+fully, the setup contains a baseline file with all errors we want to ignore. In
+particular, we ignore all errors related to not specifying the types inside arrays
+when these arrays correspond to the representation of Sass values and Sass AST nodes
+in the parser and compiler.
+When contributing, the proper process to deal with static analysis is the following:
+
+1. Make your change in the codebase
+2. Run `make phpstan`
+3. Fix errors reported by phpstan when possible
+4. Repeat step 2 and 3 until nothing gets fixed anymore at step 3
+5. Run `make phpstan-baseline` to regenerate the phpstan baseline
+
+Additions to the baseline will be reviewed to avoid ignoring errors that should have
+been fixed.

wp-content/plugins/wp-scss/scssphp/bin/pscss

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+#!/usr/bin/env php
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+error_reporting(E_ALL);
+
+if (version_compare(PHP_VERSION, '5.6') < 0) {
+    die('Requires PHP 5.6 or above');
+}
+
+include __DIR__ . '/../scss.inc.php';
+
+use ScssPhp\ScssPhp\Compiler;
+use ScssPhp\ScssPhp\Exception\SassException;
+use ScssPhp\ScssPhp\OutputStyle;
+use ScssPhp\ScssPhp\Parser;
+use ScssPhp\ScssPhp\Version;
+
+$style = null;
+$loadPaths = null;
+$dumpTree = false;
+$inputFile = null;
+$changeDir = false;
+$encoding = false;
+$sourceMap = false;
+$embedSources = false;
+$embedSourceMap = false;
+
+/**
+ * Parse argument
+ *
+ * @param integer $i
+ * @param array $options
+ *
+ * @return string|null
+ */
+function parseArgument(&$i, $options) {
+    global $argc;
+    global $argv;
+
+    if (! preg_match('/^(?:' . implode('|', (array) $options) . ')=?(.*)/', $argv[$i], $matches)) {
+        return;
+    }
+
+    if (strlen($matches[1])) {
+        return $matches[1];
+    }
+
+    if ($i + 1 < $argc) {
+        $i++;
+
+        return $argv[$i];
+    }
+}
+
+$arguments = [];
+
+for ($i = 1; $i < $argc; $i++) {
+    if ($argv[$i] === '-?' || $argv[$i] === '-h' || $argv[$i] === '--help') {
+        $exe = $argv[0];
+
+        $HELP = <<<EOT
+Usage: $exe [options] [input-file] [output-file]
+
+Options include:
+
+    --help              Show this message [-h, -?]
+    --continue-on-error [deprecated] Ignored
+    --debug-info        [deprecated] Ignored [-g]
+    --dump-tree         [deprecated] Dump formatted parse tree [-T]
+    --iso8859-1         Use iso8859-1 encoding instead of default utf-8
+    --line-numbers      [deprecated] Ignored [--line-comments]
+    --load-path=PATH    Set import path [-I]
+    --precision=N       [deprecated] Ignored. (default 10) [-p]
+    --sourcemap         Create source map file
+    --embed-sources     Embed source file contents in source maps
+    --embed-source-map  Embed the source map contents in CSS (default if writing to stdout)
+    --style=FORMAT      Set the output style (compressed or expanded) [-s, -t]
+    --version           Print the version [-v]
+
+EOT;
+        exit($HELP);
+    }
+
+    if ($argv[$i] === '-v' || $argv[$i] === '--version') {
+        exit(Version::VERSION . "\n");
+    }
+
+    // Keep parsing --continue-on-error to avoid BC breaks for scripts using it
+    if ($argv[$i] === '--continue-on-error') {
+        // TODO report it as a warning ?
+        continue;
+    }
+
+    // Keep parsing it to avoid BC breaks for scripts using it
+    if ($argv[$i] === '-g' || $argv[$i] === '--debug-info') {
+        // TODO report it as a warning ?
+        continue;
+    }
+
+    if ($argv[$i] === '--iso8859-1') {
+        $encoding = 'iso8859-1';
+        continue;
+    }
+
+    // Keep parsing it to avoid BC breaks for scripts using it
+    if ($argv[$i] === '--line-numbers' || $argv[$i] === '--line-comments') {
+        // TODO report it as a warning ?
+        continue;
+    }
+
+    if ($argv[$i] === '--sourcemap') {
+        $sourceMap = true;
+        continue;
+    }
+
+    if ($argv[$i] === '--embed-sources') {
+        $embedSources = true;
+        continue;
+    }
+
+    if ($argv[$i] === '--embed-source-map') {
+        $embedSourceMap = true;
+        continue;
+    }
+
+    if ($argv[$i] === '-T' || $argv[$i] === '--dump-tree') {
+        $dumpTree = true;
+        continue;
+    }
+
+    $value = parseArgument($i, array('-t', '-s', '--style'));
+
+    if (isset($value)) {
+        $style = $value;
+        continue;
+    }
+
+    $value = parseArgument($i, array('-I', '--load-path'));
+
+    if (isset($value)) {
+        $loadPaths = $value;
+        continue;
+    }
+
+    // Keep parsing --precision to avoid BC breaks for scripts using it
+    $value = parseArgument($i, array('-p', '--precision'));
+
+    if (isset($value)) {
+        // TODO report it as a warning ?
+        continue;
+    }
+
+    $arguments[] = $argv[$i];
+}
+
+
+if (isset($arguments[0]) && file_exists($arguments[0])) {
+    $inputFile = $arguments[0];
+    $data = file_get_contents($inputFile);
+} else {
+    $data = '';
+
+    while (! feof(STDIN)) {
+        $data .= fread(STDIN, 8192);
+    }
+}
+
+if ($dumpTree) {
+    $parser = new Parser($inputFile);
+
+    print_r(json_decode(json_encode($parser->parse($data)), true));
+
+    fwrite(STDERR, 'Warning: the --dump-tree option is deprecated. Use proper debugging tools instead.');
+
+    exit();
+}
+
+$scss = new Compiler();
+
+if ($loadPaths) {
+    $scss->setImportPaths(explode(PATH_SEPARATOR, $loadPaths));
+}
+
+if ($style) {
+    if ($style === OutputStyle::COMPRESSED || $style === OutputStyle::EXPANDED) {
+        $scss->setOutputStyle($style);
+    } else {
+        fwrite(STDERR, "WARNING: the $style style is deprecated.\n");
+        $scss->setFormatter('ScssPhp\\ScssPhp\\Formatter\\' . ucfirst($style));
+    }
+}
+
+$outputFile = isset($arguments[1]) ? $arguments[1] : null;
+$sourceMapFile = null;
+
+if ($sourceMap) {
+    $sourceMapOptions = array(
+        'outputSourceFiles' => $embedSources,
+    );
+    if ($embedSourceMap || $outputFile === null) {
+        $scss->setSourceMap(Compiler::SOURCE_MAP_INLINE);
+    } else {
+        $sourceMapFile = $outputFile . '.map';
+        $sourceMapOptions['sourceMapWriteTo'] = $sourceMapFile;
+        $sourceMapOptions['sourceMapURL'] = basename($sourceMapFile);
+        $sourceMapOptions['sourceMapBasepath'] = getcwd();
+        $sourceMapOptions['sourceMapFilename'] = basename($outputFile);
+
+        $scss->setSourceMap(Compiler::SOURCE_MAP_FILE);
+    }
+
+    $scss->setSourceMapOptions($sourceMapOptions);
+}
+
+if ($encoding) {
+    $scss->setEncoding($encoding);
+}
+
+try {
+    $result = $scss->compileString($data, $inputFile);
+} catch (SassException $e) {
+    fwrite(STDERR, 'Error: '.$e->getMessage()."\n");
+    exit(1);
+}
+
+if ($outputFile) {
+    file_put_contents($outputFile, $result->getCss());
+
+    if ($sourceMapFile !== null && $result->getSourceMap() !== null) {
+        file_put_contents($sourceMapFile, $result->getSourceMap());
+    }
+} else {
+    echo $result->getCss();
+}

wp-content/plugins/wp-scss/scssphp/composer.json

@@ -0,0 +1,118 @@
+{
+    "name": "scssphp/scssphp",
+    "type": "library",
+    "description": "scssphp is a compiler for SCSS written in PHP.",
+    "keywords": ["css", "stylesheet", "scss", "sass", "less"],
+    "homepage": "http://scssphp.github.io/scssphp/",
+    "license": [
+        "MIT"
+    ],
+    "authors": [
+        {
+            "name": "Anthon Pang",
+            "email": "apang@softwaredevelopment.ca",
+            "homepage": "https://github.com/robocoder"
+        },
+        {
+            "name": "Cédric Morin",
+            "email": "cedric@yterium.com",
+            "homepage": "https://github.com/Cerdic"
+        }
+    ],
+    "autoload": {
+        "psr-4": { "ScssPhp\\ScssPhp\\": "src/" }
+    },
+    "autoload-dev": {
+        "psr-4": { "ScssPhp\\ScssPhp\\Tests\\": "tests/" }
+    },
+    "require": {
+        "php": ">=7.2",
+        "ext-ctype": "*",
+        "ext-json": "*",
+        "league/uri": "^6.4.0",
+        "league/uri-interfaces": "^2.3"
+    },
+    "suggest": {
+        "ext-mbstring": "For best performance, mbstring should be installed as it is faster than ext-iconv",
+        "ext-iconv": "Can be used as fallback when ext-mbstring is not available"
+    },
+    "require-dev": {
+        "bamarni/composer-bin-plugin": "^1.4",
+        "phpunit/phpunit": "^8.5 || ^9.5",
+        "sass/sass-spec": "*",
+        "squizlabs/php_codesniffer": "~3.5",
+        "symfony/phpunit-bridge": "^5.1",
+        "thoughtbot/bourbon": "^7.0",
+        "twbs/bootstrap": "~5.0",
+        "twbs/bootstrap4": "4.6.1",
+        "zurb/foundation": "~6.5"
+    },
+    "repositories": [
+        {
+            "type": "package",
+            "package": {
+                "name": "sass/sass-spec",
+                "version": "2022.08.19",
+                "source": {
+                    "type": "git",
+                    "url": "https://github.com/sass/sass-spec.git",
+                    "reference": "2bdc199723a3445d5badac3ac774105698f08861"
+                },
+                "dist": {
+                    "type": "zip",
+                    "url": "https://api.github.com/repos/sass/sass-spec/zipball/2bdc199723a3445d5badac3ac774105698f08861",
+                    "reference": "2bdc199723a3445d5badac3ac774105698f08861",
+                    "shasum": ""
+                }
+            }
+        },
+        {
+            "type": "package",
+            "package": {
+                "name": "thoughtbot/bourbon",
+                "version": "v7.0.0",
+                "source": {
+                    "type": "git",
+                    "url": "https://github.com/thoughtbot/bourbon.git",
+                    "reference": "fbe338ee6807e7f7aa996d82c8a16f248bb149b3"
+                },
+                "dist": {
+                    "type": "zip",
+                    "url": "https://api.github.com/repos/thoughtbot/bourbon/zipball/fbe338ee6807e7f7aa996d82c8a16f248bb149b3",
+                    "reference": "fbe338ee6807e7f7aa996d82c8a16f248bb149b3",
+                    "shasum": ""
+                }
+            }
+        },
+        {
+            "type": "package",
+            "package": {
+                "name": "twbs/bootstrap4",
+                "version": "v4.6.1",
+                "source": {
+                    "type": "git",
+                    "url": "https://github.com/twbs/bootstrap.git",
+                    "reference": "043a03c95a2ad6738f85b65e53b9dbdfb03b8d10"
+                },
+                "dist": {
+                    "type": "zip",
+                    "url": "https://api.github.com/repos/twbs/bootstrap/zipball/043a03c95a2ad6738f85b65e53b9dbdfb03b8d10",
+                    "reference": "043a03c95a2ad6738f85b65e53b9dbdfb03b8d10",
+                    "shasum": ""
+                }
+            }
+        }
+    ],
+    "config": {
+        "sort-packages": true,
+        "allow-plugins": {
+            "bamarni/composer-bin-plugin": true
+        }
+    },
+    "extra": {
+        "bamarni-bin": {
+            "forward-command": false,
+            "bin-links": false
+        }
+    }
+}

wp-content/plugins/wp-scss/scssphp/phpcs.xml.dist

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+<?xml version="1.0"?>
+<ruleset name="PSR12 (adapted for PHP 5.6+)">
+    <rule ref="PSR12">
+        <!-- Ignore this PHP 7.1+ sniff as long as we support PHP 5.6+ -->
+        <exclude name="PSR12.Properties.ConstantVisibility.NotFound"/>
+
+        <!-- This sniff doesn't ignore comment blocks -->
+<!--
+        <exclude name="Generic.Files.LineLength"/>
+-->
+    </rule>
+</ruleset>

wp-content/plugins/wp-scss/scssphp/scss.inc.php

@@ -0,0 +1,21 @@
+<?php
+
+if (version_compare(PHP_VERSION, '7.2') < 0) {
+    throw new \Exception('scssphp requires PHP 7.2 or above');
+}
+
+if (! class_exists('ScssPhp\ScssPhp\Version')) {
+    spl_autoload_register(function ($class) {
+        if (0 !== strpos($class, 'ScssPhp\ScssPhp\\')) {
+            // Not a ScssPhp class
+            return;
+        }
+
+        $subClass = substr($class, strlen('ScssPhp\ScssPhp\\'));
+        $path = __DIR__ . '/src/' . str_replace('\\', '/', $subClass) . '.php';
+
+        if (file_exists($path)) {
+            require $path;
+        }
+    });
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/AstNode.php

@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A node in an abstract syntax tree.
+ *
+ * @internal
+ */
+interface AstNode
+{
+    public function getSpan(): FileSpan;
+
+    public function __toString(): string;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssAtRule.php

@@ -0,0 +1,35 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * An unknown plain CSS at-rule.
+ *
+ * @internal
+ */
+interface CssAtRule extends CssParentNode
+{
+    /**
+     * The name of this rule.
+     *
+     * @return CssValue<string>
+     */
+    public function getName(): CssValue;
+
+    /**
+     * The value of this rule.
+     *
+     * @return CssValue<string>|null
+     */
+    public function getValue(): ?CssValue;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssComment.php

@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A plain CSS comment.
+ *
+ * This is always a multi-line comment.
+ *
+ * @internal
+ */
+interface CssComment extends CssNode
+{
+    /**
+     * The contents of this comment, including `/*` and `* /`.
+     */
+    public function getText(): string;
+
+    /**
+     * Whether this comment starts with `/*!` and so should be preserved even in
+     * compressed mode.
+     */
+    public function isPreserved(): bool;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssDeclaration.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Value\Value;
+
+/**
+ * A plain CSS declaration (that is, a `name: value` pair).
+ *
+ * @internal
+ */
+interface CssDeclaration extends CssNode
+{
+    /**
+     * The name of this declaration.
+     *
+     * @return CssValue<string>
+     */
+    public function getName(): CssValue;
+
+    /**
+     * The value of this declaration.
+     *
+     * @return CssValue<Value>
+     */
+    public function getValue(): CssValue;
+
+    /**
+     * The span for {@see getValue} that should be emitted to the source map.
+     *
+     * When the declaration's expression is just a variable, this is the span
+     * where that variable was declared whereas `$this->getValue()->getSpan()` is the span where
+     * the variable was used. Otherwise, this is identical to `$this->getValue()->getSpan()`.
+     */
+    public function getValueSpanForMap(): FileSpan;
+
+    /**
+     * Returns whether this is a CSS Custom Property declaration.
+     */
+    public function isCustomProperty(): bool;
+
+    /**
+     * Whether this was originally parsed as a custom property declaration, as
+     * opposed to using something like `#{--foo}: ...` to cause it to be parsed
+     * as a normal Sass declaration.
+     *
+     * If this is `true`, {@see isCustomProperty} will also be `true` and {@see getValue} will
+     * contain a {@see SassString}.
+     */
+    public function isParsedAsCustomProperty(): bool;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssImport.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A plain CSS `@import`.
+ *
+ * @internal
+ */
+interface CssImport extends CssNode
+{
+    /**
+     * The URL being imported.
+     *
+     * This includes quotes.
+     *
+     * @return CssValue<string>
+     */
+    public function getUrl(): CssValue;
+
+    /**
+     * The modifiers (such as media or supports queries) attached to this import.
+     *
+     * @return CssValue<string>|null
+     */
+    public function getModifiers(): ?CssValue;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssKeyframeBlock.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A block within a `@keyframes` rule.
+ *
+ * For example, `10% {opacity: 0.5}`.
+ *
+ * @internal
+ */
+interface CssKeyframeBlock extends CssParentNode
+{
+    /**
+     * The selector for this block.
+     *
+     * @return CssValue<list<string>>
+     */
+    public function getSelector(): CssValue;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssMediaQuery.php

@@ -0,0 +1,258 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Exception\SassFormatException;
+use ScssPhp\ScssPhp\Logger\LoggerInterface;
+use ScssPhp\ScssPhp\Parser\MediaQueryParser;
+
+/**
+ * A plain CSS media query, as used in `@media` and `@import`.
+ *
+ * @internal
+ */
+final class CssMediaQuery
+{
+    public const MERGE_RESULT_EMPTY = 'empty';
+    public const MERGE_RESULT_UNREPRESENTABLE = 'unrepresentable';
+
+    /**
+     * The modifier, probably either "not" or "only".
+     *
+     * This may be `null` if no modifier is in use.
+     *
+     * @var string|null
+     * @readonly
+     */
+    private $modifier;
+
+    /**
+     * The media type, for example "screen" or "print".
+     *
+     * This may be `null`. If so, {@see $conditions} will not be empty.
+     *
+     * @var string|null
+     * @readonly
+     */
+    private $type;
+
+    /**
+     * Whether {@see $conditions} is a conjunction or a disjunction.
+     *
+     * In other words, if this is `true` this query matches when _all_
+     * {@see $conditions} are met, and if it's `false` this query matches when _any_
+     * condition in {@see $conditions} is met.
+     *
+     * If this is `false`, {@see $modifier} and {@see $type} will both be `null`.
+     *
+     * @var bool
+     * @readonly
+     */
+    private $conjunction;
+
+    /**
+     * Media conditions, including parentheses.
+     *
+     * This is anything that can appear in the [`<media-in-parens>`] production.
+     *
+     * [`<media-in-parens>`]: https://drafts.csswg.org/mediaqueries-4/#typedef-media-in-parens
+     *
+     * @var list<string>
+     * @readonly
+     */
+    private $conditions;
+
+    /**
+     * Parses a media query from $contents.
+     *
+     * If passed, $url is the name of the file from which $contents comes.
+     *
+     * @return list<CssMediaQuery>
+     *
+     * @throws SassFormatException if parsing fails
+     */
+    public static function parseList(string $contents, ?LoggerInterface $logger = null, ?string $url = null): array
+    {
+        return (new MediaQueryParser($contents, $logger, $url))->parse();
+    }
+
+    /**
+     * @param list<string> $conditions
+     */
+    private function __construct(array $conditions = [], bool $conjunction = true, ?string $type = null, ?string $modifier = null)
+    {
+        $this->modifier = $modifier;
+        $this->type = $type;
+        $this->conditions = $conditions;
+        $this->conjunction = $conjunction;
+    }
+
+    /**
+     * Creates a media query specifies a type and, optionally, conditions.
+     *
+     * This always sets {@see $conjunction} to `true`.
+     *
+     * @param list<string> $conditions
+     */
+    public static function type(?string $type, ?string $modifier = null, array $conditions = []): CssMediaQuery
+    {
+        return new CssMediaQuery($conditions, true, $type, $modifier);
+    }
+
+    /**
+     * Creates a media query that matches $conditions according to
+     * $conjunction.
+     *
+     * The $conjunction argument may not be null if $conditions is longer than
+     * a single element.
+     *
+     * @param list<string> $conditions
+     */
+    public static function condition(array $conditions, ?bool $conjunction = null): CssMediaQuery
+    {
+        if (\count($conditions) > 1 && $conjunction === null) {
+            throw new \InvalidArgumentException('If conditions is longer than one element, conjunction may not be null.');
+        }
+
+        return new CssMediaQuery($conditions, $conjunction ?? true);
+    }
+
+    public function getModifier(): ?string
+    {
+        return $this->modifier;
+    }
+
+    public function getType(): ?string
+    {
+        return $this->type;
+    }
+
+    public function isConjunction(): bool
+    {
+        return $this->conjunction;
+    }
+
+    /**
+     * @return list<string>
+     */
+    public function getConditions(): array
+    {
+        return $this->conditions;
+    }
+
+    /**
+     * Whether this media query matches all media types.
+     */
+    public function matchesAllTypes(): bool
+    {
+        return $this->type === null || strtolower($this->type) === 'all';
+    }
+
+    /**
+     * Merges this with $other to return a query that matches the intersection
+     * of both inputs.
+     *
+     * @return CssMediaQuery|string
+     * @phpstan-return CssMediaQuery|CssMediaQuery::*
+     */
+    public function merge(CssMediaQuery $other)
+    {
+        if (!$this->conjunction || !$other->conjunction) {
+            return self::MERGE_RESULT_UNREPRESENTABLE;
+        }
+
+        $ourModifier = $this->modifier !== null ? strtolower($this->modifier) : null;
+        $ourType = $this->type !== null ? strtolower($this->type) : null;
+        $theirModifier = $other->modifier !== null ? strtolower($other->modifier) : null;
+        $theirType = $other->type !== null ? strtolower($other->type) : null;
+
+        if ($ourType === null && $theirType === null) {
+            return self::condition(array_merge($this->conditions, $other->conditions), true);
+        }
+
+        if (($ourModifier === 'not') !== ($theirModifier === 'not')) {
+            if ($ourType === $theirType) {
+                $negativeConditions = $ourModifier === 'not' ? $this->conditions : $other->conditions;
+                $positiveConditions = $ourModifier === 'not' ? $other->conditions : $this->conditions;
+
+                // If the negative conditions are a subset of the positive conditions, the
+                // query is empty. For example, `not screen and (color)` has no
+                // intersection with `screen and (color) and (grid)`.
+                //
+                // However, `not screen and (color)` *does* intersect with `screen and
+                // (grid)`, because it means `not (screen and (color))` and so it allows
+                // a screen with no color but with a grid.
+                if (empty(array_diff($negativeConditions, $positiveConditions))) {
+                    return self::MERGE_RESULT_EMPTY;
+                }
+
+                return self::MERGE_RESULT_UNREPRESENTABLE;
+            }
+
+            if ($this->matchesAllTypes() || $other->matchesAllTypes()) {
+                return self::MERGE_RESULT_UNREPRESENTABLE;
+            }
+
+            if ($ourModifier === 'not') {
+                $modifier = $theirModifier;
+                $type = $theirType;
+                $conditions = $other->conditions;
+            } else {
+                $modifier = $ourModifier;
+                $type = $ourType;
+                $conditions = $this->conditions;
+            }
+        } elseif ($ourModifier === 'not') {
+            // CSS has no way of representing "neither screen nor print".
+            if ($ourType !== $theirType) {
+                return self::MERGE_RESULT_UNREPRESENTABLE;
+            }
+
+            $moreConditions = \count($this->conditions) > \count($other->conditions) ? $this->conditions : $other->conditions;
+            $fewerConditions = \count($this->conditions) > \count($other->conditions) ? $other->conditions : $this->conditions;
+
+            // If one set of features is a superset of the other, use those features
+            // because they're strictly narrower.
+            if (empty(array_diff($fewerConditions, $moreConditions))) {
+                $modifier = $ourModifier; // "not"
+                $type = $ourType;
+                $conditions = $moreConditions;
+            } else {
+                // Otherwise, there's no way to represent the intersection.
+                return self::MERGE_RESULT_UNREPRESENTABLE;
+            }
+        } elseif ($this->matchesAllTypes()) {
+            $modifier = $theirModifier;
+            // Omit the type if either input query did, since that indicates that they
+            // aren't targeting a browser that requires "all and".
+            $type = $other->matchesAllTypes() && $ourType === null ? null : $theirType;
+            $conditions = array_merge($this->conditions, $other->conditions);
+        } elseif ($other->matchesAllTypes()) {
+            $modifier = $ourModifier;
+            $type = $ourType;
+            $conditions = array_merge($this->conditions, $other->conditions);
+        } elseif ($ourType !== $theirType) {
+            return self::MERGE_RESULT_EMPTY;
+        } else {
+            $modifier = $ourModifier ?? $theirModifier;
+            $type = $ourType;
+            $conditions = array_merge($this->conditions, $other->conditions);
+        }
+
+        return CssMediaQuery::type(
+            $type === $ourType ? $this->type : $other->type,
+            $modifier === $ourModifier ? $this->modifier : $other->modifier,
+            $conditions
+        );
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssMediaRule.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A plain CSS `@media` rule.
+ *
+ * @internal
+ */
+interface CssMediaRule extends CssParentNode
+{
+    /**
+     * The queries for this rule.
+     *
+     * This is never empty.
+     *
+     * @return list<CssMediaQuery>
+     */
+    public function getQueries(): array;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssNode.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Ast\AstNode;
+use ScssPhp\ScssPhp\Visitor\CssVisitor;
+
+/**
+ * A statement in a plain CSS syntax tree.
+ *
+ * @internal
+ */
+interface CssNode extends AstNode
+{
+    /**
+     * Whether this was generated from the last node in a nested Sass tree that
+     * got flattened during evaluation.
+     */
+    public function isGroupEnd(): bool;
+
+    /**
+     * Calls the appropriate visit method on $visitor.
+     *
+     * @template T
+     *
+     * @param CssVisitor<T> $visitor
+     *
+     * @return T
+     */
+    public function accept($visitor);
+
+    /**
+     * Whether this is invisible and won't be emitted to the compiled stylesheet.
+     *
+     * Note that this doesn't consider nodes that contain loud comments to be
+     * invisible even though they're omitted in compressed mode.
+     */
+    public function isInvisible(): bool;
+
+    /**
+     * Whether this node would be invisible even if style rule selectors within it
+     * didn't have bogus combinators.
+     *
+     * Note that this doesn't consider nodes that contain loud comments to be
+     * invisible even though they're omitted in compressed mode.
+     */
+    public function isInvisibleOtherThanBogusCombinators(): bool;
+
+    /**
+     * Whether this node will be invisible when loud comments are stripped.
+     */
+    public function isInvisibleHidingComments(): bool;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssParentNode.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A {@see CssNode} that can have child statements.
+ *
+ * @internal
+ */
+interface CssParentNode extends CssNode
+{
+    /**
+     * The child statements of this node.
+     *
+     * @return list<CssNode>
+     */
+    public function getChildren(): array;
+
+    /**
+     * Whether the rule has no children and should be emitted without curly
+     * braces.
+     *
+     * This implies `children.isEmpty`, but the reverse is not true—for a rule
+     * like `@foo {}`, {@see getChildren} is empty but {@see isChildless} is `false`.
+     */
+    public function isChildless(): bool;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssStyleRule.php

@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Ast\Selector\SelectorList;
+
+/**
+ * A plain CSS style rule.
+*  *
+*  * This applies style declarations to elements that match a given selector.
+*  * Note that this isn't *strictly* plain CSS, since {@see getSelector} may still
+*  * contain placeholder selectors.
+ *
+ * @internal
+ */
+interface CssStyleRule extends CssParentNode
+{
+    /**
+     * The selector for this rule.
+     *
+     * @return CssValue<SelectorList>
+     */
+    public function getSelector(): CssValue;
+
+    /**
+     * The selector for this rule, before any extensions were applied.
+     */
+    public function getOriginalSelector(): SelectorList;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssStylesheet.php

@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A plain CSS stylesheet.
+ *
+ * This is the root plain CSS node. It contains top-level statements.
+ *
+ * @internal
+ */
+interface CssStylesheet extends CssParentNode
+{
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssSupportsRule.php

@@ -0,0 +1,28 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A plain CSS `@supports` rule.
+ *
+ * @internal
+ */
+interface CssSupportsRule extends CssParentNode
+{
+    /**
+     * The supports condition.
+     *
+     * @return CssValue<string>
+     */
+    public function getCondition(): CssValue;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/CssValue.php

@@ -0,0 +1,71 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Ast\AstNode;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A value in a plain CSS tree.
+ *
+ * This is used to associate a span with a value that doesn't otherwise track
+ * its span.
+ *
+ * @template T
+ *
+ * @internal
+ */
+class CssValue implements AstNode
+{
+    /**
+     * @phpstan-var T
+     */
+    protected $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param T $value
+     */
+    public function __construct($value, FileSpan $span)
+    {
+        $this->value = $value;
+        $this->span = $span;
+    }
+
+    /**
+     * @return T
+     */
+    public function getValue()
+    {
+        return $this->value;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function __toString(): string
+    {
+        if (\is_array($this->value)) {
+            return implode($this->value);
+        }
+
+        return (string) $this->value;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/IsInvisibleVisitor.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Visitor\EveryCssVisitor;
+
+/**
+ * The visitor used to implement {@see CssNode::isInvisible}
+ *
+ * @internal
+ */
+final class IsInvisibleVisitor extends EveryCssVisitor
+{
+    /**
+     * Whether to consider selectors with bogus combinators invisible.
+     *
+     * @var bool
+     * @readonly
+     */
+    private $includeBogus;
+
+    /**
+     * Whether to consider comments invisible.
+     *
+     * @var bool
+     * @readonly
+     */
+    private $includeComments;
+
+    public function __construct(bool $includeBogus, bool $includeComments)
+    {
+        $this->includeBogus = $includeBogus;
+        $this->includeComments = $includeComments;
+    }
+
+    public function visitCssAtRule($node): bool
+    {
+        // An unknown at-rule is never invisible. Because we don't know the semantics
+        // of unknown rules, we can't guarantee that (for example) `@foo {}` isn't
+        // meaningful.
+        return false;
+    }
+
+    public function visitCssComment($node): bool
+    {
+        return $this->includeComments && !$node->isPreserved();
+    }
+
+    public function visitCssStyleRule($node): bool
+    {
+        return ($this->includeBogus ? $node->getSelector()->getValue()->isInvisible() : $node->getSelector()->getValue()->isInvisibleOtherThanBogusCombinators()) || parent::visitCssStyleRule($node);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssAtRule.php

@@ -0,0 +1,103 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssAtRule} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssAtRule extends ModifiableCssParentNode implements CssAtRule
+{
+    /**
+     * @var CssValue<string>
+     */
+    private $name;
+
+    /**
+     * @var CssValue<string>|null
+     */
+    private $value;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $childless;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param CssValue<string>      $name
+     * @param CssValue<string>|null $value
+     * @param bool                  $childless
+     * @param FileSpan              $span
+     */
+    public function __construct(CssValue $name, FileSpan $span, bool $childless = false, ?CssValue $value = null)
+    {
+        parent::__construct();
+
+        $this->name = $name;
+        $this->value = $value;
+        $this->childless = $childless;
+        $this->span = $span;
+    }
+
+    public function getName(): CssValue
+    {
+        return $this->name;
+    }
+
+    public function getValue(): ?CssValue
+    {
+        return $this->value;
+    }
+
+    public function isChildless(): bool
+    {
+        return $this->childless;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssAtRule($this);
+    }
+
+    /**
+     * @phpstan-return ModifiableCssAtRule
+     */
+    public function copyWithoutChildren(): ModifiableCssParentNode
+    {
+        return new ModifiableCssAtRule($this->name, $this->span, $this->childless, $this->value);
+    }
+
+    public function addChild(ModifiableCssNode $child): void
+    {
+        if ($this->childless) {
+            throw new \LogicException('Cannot add a child in a childless at-rule.');
+        }
+
+        parent::addChild($child);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssComment.php

@@ -0,0 +1,61 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssComment} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssComment extends ModifiableCssNode implements CssComment
+{
+    /**
+     * @var string
+     * @readonly
+     */
+    private $text;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $text, FileSpan $span)
+    {
+        $this->text = $text;
+        $this->span = $span;
+    }
+
+    public function getText(): string
+    {
+        return $this->text;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function isPreserved(): bool
+    {
+        return $this->text[2] === '!';
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssComment($this);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssDeclaration.php

@@ -0,0 +1,115 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Value\SassString;
+use ScssPhp\ScssPhp\Value\Value;
+
+/**
+ * A modifiable version of {@see CssDeclaration} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssDeclaration extends ModifiableCssNode implements CssDeclaration
+{
+    /**
+     * @var CssValue<string>
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var CssValue<Value>
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $parsedAsCustomProperty;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $valueSpanForMap;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param CssValue<string> $name
+     * @param CssValue<Value>  $value
+     * @param bool             $parsedAsCustomProperty
+     * @param FileSpan         $valueSpanForMap
+     * @param FileSpan         $span
+     */
+    public function __construct(CssValue $name, CssValue $value, FileSpan $span, bool $parsedAsCustomProperty, ?FileSpan $valueSpanForMap = null) {
+        $this->name = $name;
+        $this->value = $value;
+        $this->parsedAsCustomProperty = $parsedAsCustomProperty;
+        $this->valueSpanForMap = $valueSpanForMap ?? $value->getSpan();
+        $this->span = $span;
+
+        if ($parsedAsCustomProperty) {
+            if (!$this->isCustomProperty()) {
+                throw new \InvalidArgumentException('parsedAsCustomProperty must be false if name doesn\'t begin with "--".');
+            }
+
+            if (!$value->getValue() instanceof SassString) {
+                throw new \InvalidArgumentException(sprintf('If parsedAsCustomProperty is true, value must contain a SassString (was %s).', get_class($value->getValue())));
+            }
+        }
+    }
+
+    public function getName(): CssValue
+    {
+        return $this->name;
+    }
+
+    public function getValue(): CssValue
+    {
+        return $this->value;
+    }
+
+    public function isParsedAsCustomProperty(): bool
+    {
+        return $this->parsedAsCustomProperty;
+    }
+
+    public function getValueSpanForMap(): FileSpan
+    {
+        return $this->valueSpanForMap;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function isCustomProperty(): bool
+    {
+        return 0 === strpos($this->name->getValue(), '--');
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssDeclaration($this);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssImport.php

@@ -0,0 +1,77 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssImport} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssImport extends ModifiableCssNode implements CssImport
+{
+    /**
+     * The URL being imported.
+     *
+     * This includes quotes.
+     *
+     * @var CssValue<string>
+     * @readonly
+     */
+    private $url;
+
+    /**
+     * @var CssValue<string>|null
+     * @readonly
+     */
+    private $modifiers;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param CssValue<string>         $url
+     * @param FileSpan                 $span
+     * @param CssValue<string>|null    $modifiers
+     */
+    public function __construct(CssValue $url, FileSpan $span, ?CssValue $modifiers = null)
+    {
+        $this->url = $url;
+        $this->modifiers = $modifiers;
+        $this->span = $span;
+    }
+
+    public function getUrl(): CssValue
+    {
+        return $this->url;
+    }
+
+    public function getModifiers(): ?CssValue
+    {
+        return $this->modifiers;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssImport($this);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssKeyframeBlock.php

@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssKeyframeBlock} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssKeyframeBlock extends ModifiableCssParentNode implements CssKeyframeBlock
+{
+    /**
+     * @var CssValue<list<string>>
+     * @readonly
+     */
+    private $selector;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param CssValue<list<string>> $selector
+     * @param FileSpan               $span
+     */
+    public function __construct(CssValue $selector, FileSpan $span)
+    {
+        parent::__construct();
+        $this->selector = $selector;
+        $this->span = $span;
+    }
+
+    public function getSelector(): CssValue
+    {
+        return $this->selector;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssKeyframeBlock($this);
+    }
+
+    /**
+     * @phpstan-return ModifiableCssKeyframeBlock
+     */
+    public function copyWithoutChildren(): ModifiableCssParentNode
+    {
+        return new ModifiableCssKeyframeBlock($this->selector, $this->span);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssMediaRule.php

@@ -0,0 +1,65 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssMediaRule} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssMediaRule extends ModifiableCssParentNode implements CssMediaRule
+{
+    /**
+     * @var list<CssMediaQuery>
+     */
+    private $queries;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param CssMediaQuery[] $queries
+     * @param FileSpan        $span
+     */
+    public function __construct(array $queries, FileSpan $span)
+    {
+        parent::__construct();
+        $this->queries = $queries;
+        $this->span = $span;
+    }
+
+    public function getQueries(): array
+    {
+        return $this->queries;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssMediaRule($this);
+    }
+
+    public function copyWithoutChildren(): ModifiableCssParentNode
+    {
+        return new ModifiableCssMediaRule($this->queries, $this->span);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssNode.php

@@ -0,0 +1,151 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Serializer\Serializer;
+use ScssPhp\ScssPhp\Visitor\ModifiableCssVisitor;
+
+/**
+ * A modifiable version of {@see CssNode}.
+ *
+ * Almost all CSS nodes are the modifiable classes under the covers. However,
+ * modification should only be done within the evaluation step, so the
+ * unmodifiable types are used elsewhere to enforce that constraint.
+ *
+ * @internal
+ */
+abstract class ModifiableCssNode implements CssNode
+{
+    /**
+     * @var ModifiableCssParentNode|null
+     */
+    private $parent;
+
+    /**
+     * The index of `$this` in parent's children.
+     *
+     * This makes {@see remove} more efficient.
+     *
+     * @var int|null
+     */
+    private $indexInParent;
+
+    /**
+     * @var bool
+     */
+    private $groupEnd = false;
+
+    public function getParent(): ?ModifiableCssParentNode
+    {
+        return $this->parent;
+    }
+
+    protected function setParent(ModifiableCssParentNode $parent, int $indexInParent): void
+    {
+        $this->parent = $parent;
+        $this->indexInParent = $indexInParent;
+    }
+
+    public function isGroupEnd(): bool
+    {
+        return $this->groupEnd;
+    }
+
+    public function setGroupEnd(bool $groupEnd): void
+    {
+        $this->groupEnd = $groupEnd;
+    }
+
+    /**
+     * Whether this node has a visible sibling after it.
+     */
+    public function hasFollowingSibling(): bool
+    {
+        $parent = $this->parent;
+
+        if ($parent === null) {
+            return false;
+        }
+
+        assert($this->indexInParent !== null);
+        $siblings = $parent->getChildren();
+
+        for ($i = $this->indexInParent + 1; $i < \count($siblings); $i++) {
+            $sibling = $siblings[$i];
+
+            if (!$sibling->isInvisible()) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    public function isInvisible(): bool
+    {
+        return $this->accept(new IsInvisibleVisitor(true, false));
+    }
+
+    public function isInvisibleOtherThanBogusCombinators(): bool
+    {
+        return $this->accept(new IsInvisibleVisitor(false, false));
+    }
+
+    public function isInvisibleHidingComments(): bool
+    {
+        return $this->accept(new IsInvisibleVisitor(true, true));
+    }
+
+    /**
+     * Calls the appropriate visit method on $visitor.
+     *
+     * @template T
+     *
+     * @param ModifiableCssVisitor<T> $visitor
+     *
+     * @return T
+     */
+    abstract public function accept($visitor);
+
+    /**
+     * Removes $this from {@see parent}'s child list.
+     *
+     * @throws \LogicException if {@see parent} is `null`.
+     */
+    public function remove(): void
+    {
+        $parent = $this->parent;
+
+        if ($parent === null) {
+            throw new \LogicException("Can't remove a node without a parent.");
+        }
+
+        assert($this->indexInParent !== null);
+
+        $parent->removeChildAt($this->indexInParent);
+        $children = $parent->getChildren();
+
+        for ($i = $this->indexInParent; $i < \count($children); $i++) {
+            $child = $children[$i];
+            assert($child->indexInParent !== null);
+            $child->indexInParent = $child->indexInParent - 1;
+        }
+        $this->parent = null;
+        $this->indexInParent = null;
+    }
+
+    public function __toString(): string
+    {
+        return Serializer::serialize($this, true)->getCss();
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssParentNode.php

@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A modifiable version of {@see CssParentNode} for use in the evaluation step.
+ *
+ * @internal
+ */
+abstract class ModifiableCssParentNode extends ModifiableCssNode implements CssParentNode
+{
+    /**
+     * @var list<ModifiableCssNode>
+     */
+    private $children;
+
+    /**
+     * @param list<ModifiableCssNode> $children
+     */
+    public function __construct(array $children = [])
+    {
+        $this->children = $children;
+    }
+
+    /**
+     * @return list<ModifiableCssNode>
+     */
+    public function getChildren(): array
+    {
+        return $this->children;
+    }
+
+    public function isChildless(): bool
+    {
+        return false;
+    }
+
+    /**
+     * Returns a copy of $this with an empty {@see children} list.
+     *
+     * This is *not* a deep copy. If other parts of this node are modifiable,
+     * they are shared between the new and old nodes.
+     */
+    abstract public function copyWithoutChildren(): ModifiableCssParentNode;
+
+    public function addChild(ModifiableCssNode $child): void
+    {
+        $child->setParent($this, \count($this->children));
+        $this->children[] = $child;
+    }
+
+    /**
+     * @internal
+     */
+    public function removeChildAt(int $index): void
+    {
+        array_splice($this->children, $index, 1);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssStyleRule.php

@@ -0,0 +1,86 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\Ast\Selector\SelectorList;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssStyleRule} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssStyleRule extends ModifiableCssParentNode implements CssStyleRule
+{
+    /**
+     * @var ModifiableCssValue<SelectorList>
+     * @readonly
+     */
+    private $selector;
+
+    /**
+     * @var SelectorList
+     * @readonly
+     */
+    private $originalSelector;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param ModifiableCssValue<SelectorList> $selector
+     * @param FileSpan                         $span
+     * @param SelectorList|null                $originalSelector
+     */
+    public function __construct(ModifiableCssValue $selector, FileSpan $span, ?SelectorList $originalSelector = null)
+    {
+        parent::__construct();
+        $this->selector = $selector;
+        $this->originalSelector = $originalSelector ?? $selector->getValue();
+        $this->span = $span;
+    }
+
+    /**
+     * @phpstan-return ModifiableCssValue<SelectorList>
+     */
+    public function getSelector(): CssValue
+    {
+        return $this->selector;
+    }
+
+    public function getOriginalSelector(): SelectorList
+    {
+        return $this->originalSelector;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssStyleRule($this);
+    }
+
+    /**
+     * @phpstan-return ModifiableCssStyleRule
+     */
+    public function copyWithoutChildren(): ModifiableCssParentNode
+    {
+        return new ModifiableCssStyleRule($this->selector, $this->span, $this->originalSelector);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssStylesheet.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssStylesheet} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssStylesheet extends ModifiableCssParentNode implements CssStylesheet
+{
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param FileSpan $span
+     * @param list<ModifiableCssNode> $children
+     */
+    public function __construct(FileSpan $span, array $children = [])
+    {
+        parent::__construct($children);
+        $this->span = $span;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssStylesheet($this);
+    }
+
+    /**
+     * @phpstan-return ModifiableCssStylesheet
+     */
+    public function copyWithoutChildren(): ModifiableCssParentNode
+    {
+        return new ModifiableCssStylesheet($this->span);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssSupportsRule.php

@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A modifiable version of {@see CssSupportsRule} for use in the evaluation step.
+ *
+ * @internal
+ */
+final class ModifiableCssSupportsRule extends ModifiableCssParentNode implements CssSupportsRule
+{
+    /**
+     * @var CssValue<string>
+     * @readonly
+     */
+    private $condition;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param CssValue<string> $condition
+     * @param FileSpan         $span
+     */
+    public function __construct(CssValue $condition, FileSpan $span)
+    {
+        parent::__construct();
+        $this->condition = $condition;
+        $this->span = $span;
+    }
+
+    public function getCondition(): CssValue
+    {
+        return $this->condition;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept($visitor)
+    {
+        return $visitor->visitCssSupportsRule($this);
+    }
+
+    /**
+     * @phpstan-return ModifiableCssSupportsRule
+     */
+    public function copyWithoutChildren(): ModifiableCssParentNode
+    {
+        return new ModifiableCssSupportsRule($this->condition, $this->span);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Css/ModifiableCssValue.php

@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Css;
+
+/**
+ * A modifiable version of {@see CssValue} for use in the evaluation step.
+ *
+ * @template T
+ * @template-extends CssValue<T>
+ *
+ * @internal
+ */
+final class ModifiableCssValue extends CssValue
+{
+    /**
+     * @param T $value
+     */
+    public function setValue($value): void
+    {
+        $this->value = $value;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/FakeAstNode.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * An {@see AstNode} that just exposes a single span generated by a callback.
+ *
+ * @internal
+ */
+final class FakeAstNode implements AstNode
+{
+    /**
+     * @var callable(): FileSpan
+     * @readonly
+     */
+    private $callback;
+
+    /**
+     * @param callable(): FileSpan $callback
+     */
+    public function __construct(callable $callback)
+    {
+        $this->callback = $callback;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return ($this->callback)();
+    }
+
+    public function __toString(): string
+    {
+        return '';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Argument.php

@@ -0,0 +1,99 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+
+/**
+ * An argument declared as part of an {@see ArgumentDeclaration}.
+ *
+ * @internal
+ */
+final class Argument implements SassNode, SassDeclaration
+{
+    /**
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var Expression|null
+     * @readonly
+     */
+    private $defaultValue;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $name, FileSpan $span, ?Expression $defaultValue = null)
+    {
+        $this->name = $name;
+        $this->defaultValue = $defaultValue;
+        $this->span = $span;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * The variable name as written in the document, without underscores
+     * converted to hyphens and including the leading `$`.
+     *
+     * This isn't particularly efficient, and should only be used for error
+     * messages.
+     */
+    public function getOriginalName(): string
+    {
+        if ($this->defaultValue === null) {
+            return $this->span->getText();
+        }
+
+        return Util::declarationName($this->span);
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        if ($this->defaultValue === null) {
+            return $this->span;
+        }
+
+        return SpanUtil::initialIdentifier($this->span, 1);
+    }
+
+    public function getDefaultValue(): ?Expression
+    {
+        return $this->defaultValue;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function __toString(): string
+    {
+        if ($this->defaultValue === null) {
+            return $this->name;
+        }
+
+        return $this->name . ': ' . $this->defaultValue;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/ArgumentDeclaration.php

@@ -0,0 +1,228 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\Exception\SassFormatException;
+use ScssPhp\ScssPhp\Exception\SassScriptException;
+use ScssPhp\ScssPhp\Logger\LoggerInterface;
+use ScssPhp\ScssPhp\Parser\ScssParser;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * An argument declaration, as for a function or mixin definition.
+ *
+ * @internal
+ */
+final class ArgumentDeclaration implements SassNode
+{
+    /**
+     * @var list<Argument>
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var string|null
+     * @readonly
+     */
+    private $restArgument;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param list<Argument> $arguments
+     * @param FileSpan      $span
+     * @param string|null $restArgument
+     */
+    public function __construct(array $arguments, FileSpan $span, ?string $restArgument = null)
+    {
+        $this->arguments = $arguments;
+        $this->restArgument = $restArgument;
+        $this->span = $span;
+    }
+
+    public static function createEmpty(FileSpan $span): ArgumentDeclaration
+    {
+        return new self([], $span);
+    }
+
+    /**
+     * Parses an argument declaration from $contents, which should be of the
+     * form `@rule name(args) {`.
+     *
+     * If passed, $url is the name of the file from which $contents comes.
+     *
+     * @throws SassFormatException if parsing fails.
+     */
+    public static function parse(string $contents, ?LoggerInterface $logger = null, ?string $url = null): ArgumentDeclaration
+    {
+        return (new ScssParser($contents, $logger, $url))->parseArgumentDeclaration();
+    }
+
+    public function isEmpty(): bool
+    {
+        return \count($this->arguments) === 0 && $this->restArgument === null;
+    }
+
+    /**
+     * @return list<Argument>
+     */
+    public function getArguments(): array
+    {
+        return $this->arguments;
+    }
+
+    public function getRestArgument(): ?string
+    {
+        return $this->restArgument;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    /**
+     * @param int                  $positional
+     * @param array<string, mixed> $names Only keys are relevant
+     *
+     * @throws SassScriptException if $positional and $names aren't valid for this argument declaration.
+     */
+    public function verify(int $positional, array $names): void
+    {
+        $nameUsed = 0;
+
+        foreach ($this->arguments as $i => $argument) {
+            if ($i < $positional) {
+                if (isset($names[$argument->getName()])) {
+                    $originalName = $this->originalArgumentName($argument->getName());
+                    throw new SassScriptException(sprintf('Argument $%s was passed both by position and by name.', $originalName));
+                }
+            } elseif (isset($names[$argument->getName()])) {
+                $nameUsed++;
+            } elseif ($argument->getDefaultValue() === null) {
+                $originalName = $this->originalArgumentName($argument->getName());
+                throw new SassScriptException(sprintf('Missing argument $%s', $originalName));
+            }
+        }
+
+        if ($this->restArgument !== null) {
+            return;
+        }
+
+        if ($positional > \count($this->arguments)) {
+            $message = sprintf(
+                'Only %d %sargument%s allowed, but %d %s passed.',
+                \count($this->arguments),
+                empty($names) ? '' : 'positional ',
+                \count($this->arguments) === 1 ? '' : 's',
+                $positional,
+                $positional === 1 ? 'was' : 'were'
+            );
+            throw new SassScriptException($message);
+        }
+
+        if ($nameUsed < \count($names)) {
+            $unknownNames = array_values(array_diff(array_keys($names), array_map(function ($argument) {
+                return $argument->getName();
+            }, $this->arguments)));
+            $lastName = array_pop($unknownNames);
+            $message = sprintf(
+                'No argument%s named $%s%s.',
+                $unknownNames ? 's' : '',
+                $unknownNames ? implode(', $', $unknownNames) . ' or $' : '',
+                $lastName
+            );
+            throw new SassScriptException($message);
+        }
+    }
+
+    private function originalArgumentName(string $name): string
+    {
+        if ($name === $this->restArgument) {
+            $text = $this->span->getText();
+            $lastDollar = strrpos($text, '$');
+            assert($lastDollar !== false);
+            $fromDollar = substr($text, $lastDollar);
+            $dot = strrpos($fromDollar, '.');
+            assert($dot !== false);
+
+            return substr($fromDollar, 0, $dot);
+        }
+
+        foreach ($this->arguments as $argument) {
+            if ($argument->getName() === $name) {
+                return $argument->getOriginalName();
+            }
+        }
+
+        throw new \InvalidArgumentException("This declaration has no argument named \"\$$name\".");
+    }
+
+    /**
+     * Returns whether $positional and $names are valid for this argument
+     * declaration.
+     *
+     * @param int                  $positional
+     * @param array<string, mixed> $names Only keys are relevant
+     *
+     * @return bool
+     */
+    public function matches(int $positional, array $names): bool
+    {
+        $nameUsed = 0;
+
+        foreach ($this->arguments as $i => $argument) {
+            if ($i < $positional) {
+                if (isset($names[$argument->getName()])) {
+                    return false;
+                }
+            } elseif (isset($names[$argument->getName()])) {
+                $nameUsed++;
+            } elseif ($argument->getDefaultValue() === null) {
+                return false;
+            }
+        }
+
+        if ($this->restArgument !== null) {
+            return true;
+        }
+
+        if ($positional > \count($this->arguments)) {
+            return false;
+        }
+
+        if ($nameUsed < \count($names)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    public function __toString(): string
+    {
+        $parts = [];
+        foreach ($this->arguments as $arg) {
+            $parts[] = "\$$arg";
+        }
+        if ($this->restArgument !== null) {
+            $parts[] = "\$$this->restArgument...";
+        }
+
+        return implode(', ', $parts);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/ArgumentInvocation.php

@@ -0,0 +1,127 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A set of arguments passed in to a function or mixin.
+ *
+ * @internal
+ */
+final class ArgumentInvocation implements SassNode
+{
+    /**
+     * @var list<Expression>
+     * @readonly
+     */
+    private $positional;
+
+    /**
+     * @var array<string, Expression>
+     * @readonly
+     */
+    private $named;
+
+    /**
+     * @var Expression|null
+     * @readonly
+     */
+    private $rest;
+
+    /**
+     * @var Expression|null
+     */
+    private $keywordRest;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param list<Expression>          $positional
+     * @param array<string, Expression> $named
+     * @param FileSpan                  $span
+     * @param Expression|null           $rest
+     * @param Expression|null           $keywordRest
+     */
+    public function __construct(array $positional, array $named, FileSpan $span, ?Expression $rest = null, ?Expression $keywordRest = null)
+    {
+        assert($keywordRest === null || $rest !== null);
+
+        $this->positional = $positional;
+        $this->named = $named;
+        $this->rest = $rest;
+        $this->keywordRest = $keywordRest;
+        $this->span = $span;
+    }
+
+    public static function createEmpty(FileSpan $span): ArgumentInvocation
+    {
+        return new self([], [], $span);
+    }
+
+    public function isEmpty(): bool
+    {
+        return \count($this->positional) === 0 && \count($this->named) === 0 && $this->rest === null;
+    }
+
+    /**
+     * @return list<Expression>
+     */
+    public function getPositional(): array
+    {
+        return $this->positional;
+    }
+
+    /**
+     * @return array<string, Expression>
+     */
+    public function getNamed(): array
+    {
+        return $this->named;
+    }
+
+    public function getRest(): ?Expression
+    {
+        return $this->rest;
+    }
+
+    public function getKeywordRest(): ?Expression
+    {
+        return $this->keywordRest;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function __toString(): string
+    {
+        $parts = $this->positional;
+        foreach ($this->named as $name => $arg) {
+            $parts[] = "\$$name: $arg";
+        }
+        if ($this->rest !== null) {
+            $parts[] = "$this->rest...";
+        }
+        if ($this->keywordRest !== null) {
+            $parts[] = "$this->keywordRest...";
+        }
+
+        return '(' . implode(', ', $parts) . ')';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/AtRootQuery.php

@@ -0,0 +1,167 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\Ast\Css\CssAtRule;
+use ScssPhp\ScssPhp\Ast\Css\CssMediaRule;
+use ScssPhp\ScssPhp\Ast\Css\CssParentNode;
+use ScssPhp\ScssPhp\Ast\Css\CssStyleRule;
+use ScssPhp\ScssPhp\Ast\Css\CssSupportsRule;
+use ScssPhp\ScssPhp\Exception\SassFormatException;
+use ScssPhp\ScssPhp\Logger\LoggerInterface;
+use ScssPhp\ScssPhp\Parser\AtRootQueryParser;
+
+/**
+ * A query for the `@at-root` rule.
+ *
+ * @internal
+ */
+final class AtRootQuery
+{
+    /**
+     * Whether the query includes or excludes rules with the specified names.
+     *
+     * @var bool
+     * @readonly
+     */
+    private $include;
+
+    /**
+     * The names of the rules included or excluded by this query.
+     *
+     * There are two special names. "all" indicates that all rules are included
+     * or excluded, and "rule" indicates style rules are included or excluded.
+     *
+     * @var string[]
+     * @readonly
+     */
+    private $names;
+
+    /**
+     * Whether this includes or excludes *all* rules.
+     *
+     * @var bool
+     * @readonly
+     */
+    private $all;
+
+    /**
+     * Whether this includes or excludes style rules.
+     *
+     * @var bool
+     * @readonly
+     */
+    private $rule;
+
+    /**
+     * Parses an at-root query from $contents.
+     *
+     * If passed, $url is the name of the file from which $contents comes.
+     *
+     * @throws SassFormatException if parsing fails
+     */
+    public static function parse(string $contents, ?LoggerInterface $logger = null, ?string $url = null): AtRootQuery
+    {
+        return (new AtRootQueryParser($contents, $logger, $url))->parse();
+    }
+
+    /**
+     * @param string[] $names
+     * @param bool     $include
+     */
+    public static function create(array $names, bool $include): AtRootQuery
+    {
+        return new AtRootQuery($names, $include, \in_array('all', $names, true), \in_array('rule', $names, true));
+    }
+
+    /**
+     * The default at-root query
+     */
+    public static function getDefault(): AtRootQuery
+    {
+        return new AtRootQuery([], false, false, true);
+    }
+
+    /**
+     * @param string[] $names
+     * @param bool     $include
+     * @param bool     $all
+     * @param bool     $rule
+     */
+    private function __construct(array $names, bool $include, bool $all, bool $rule)
+    {
+        $this->include = $include;
+        $this->names = $names;
+        $this->all = $all;
+        $this->rule = $rule;
+    }
+
+    public function getInclude(): bool
+    {
+        return $this->include;
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getNames(): array
+    {
+        return $this->names;
+    }
+
+    /**
+     * Whether this excludes style rules.
+     *
+     * Note that this takes {@see include} into account.
+     */
+    public function excludesStyleRules(): bool
+    {
+        return ($this->all || $this->rule) !== $this->include;
+    }
+
+    /**
+     * Returns whether $this excludes $node
+     */
+    public function excludes(CssParentNode $node): bool
+    {
+        if ($this->all) {
+            return !$this->include;
+        }
+
+        if ($node instanceof CssStyleRule) {
+            return $this->excludesStyleRules();
+        }
+
+        if ($node instanceof CssMediaRule) {
+            return $this->excludesName('media');
+        }
+
+        if ($node instanceof CssSupportsRule) {
+            return $this->excludesName('supports');
+        }
+
+        if ($node instanceof CssAtRule) {
+            return $this->excludesName(strtolower($node->getName()->getValue()));
+        }
+
+        return false;
+    }
+
+    /**
+     * Returns whether $this excludes an at-rule with the given $name.
+     */
+    public function excludesName(string $name): bool
+    {
+        return ($this->all || \in_array($name, $this->names, true)) !== $this->include;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/CallableInvocation.php

@@ -0,0 +1,18 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+interface CallableInvocation extends SassNode
+{
+    public function getArguments(): ArgumentInvocation;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/ConfiguredVariable.php

@@ -0,0 +1,86 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+
+/**
+ * A variable configured by a `with` clause in a `@use` or `@forward` rule.
+ *
+ * @internal
+ */
+final class ConfiguredVariable implements SassNode, SassDeclaration
+{
+    /**
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $guarded;
+
+    public function __construct(string $name, Expression $expression, FileSpan $span, bool $guarded = false)
+    {
+        $this->name = $name;
+        $this->expression = $expression;
+        $this->span = $span;
+        $this->guarded = $guarded;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function isGuarded(): bool
+    {
+        return $this->guarded;
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        return SpanUtil::initialIdentifier($this->span, 1);
+    }
+
+    public function __toString(): string
+    {
+        return '$' . $this->name . ': ' . $this->expression . ($this->guarded ? ' !default' : '');
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A SassScript expression in a Sass syntax tree.
+ *
+ * @internal
+ */
+interface Expression extends SassNode
+{
+    /**
+     * @template T
+     * @param ExpressionVisitor<T> $visitor
+     * @return T
+     */
+    public function accept(ExpressionVisitor $visitor);
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/BinaryOperationExpression.php

@@ -0,0 +1,148 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A binary operator, as in `1 + 2` or `$this and $other`.
+ *
+ * @internal
+ */
+final class BinaryOperationExpression implements Expression
+{
+    /**
+     * @var BinaryOperator::*
+     * @readonly
+     */
+    private $operator;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $left;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $right;
+
+    /**
+     * Whether this is a dividedBy operation that may be interpreted as slash-separated numbers.
+     *
+     * @var bool
+     */
+    private $allowsSlash = false;
+
+    /**
+     * @param BinaryOperator::* $operator
+     */
+    public function __construct(string $operator, Expression $left, Expression $right)
+    {
+        $this->operator = $operator;
+        $this->left = $left;
+        $this->right = $right;
+    }
+
+    /**
+     * Creates a dividedBy operation that may be interpreted as slash-separated numbers.
+     */
+    public static function slash(Expression $left, Expression $right): self
+    {
+        $operation = new self(BinaryOperator::DIVIDED_BY, $left, $right);
+        $operation->allowsSlash = true;
+
+        return $operation;
+    }
+
+    /**
+     * @return BinaryOperator::*
+     */
+    public function getOperator(): string
+    {
+        return $this->operator;
+    }
+
+    public function getLeft(): Expression
+    {
+        return $this->left;
+    }
+
+    public function getRight(): Expression
+    {
+        return $this->right;
+    }
+
+    public function allowsSlash(): bool
+    {
+        return $this->allowsSlash;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        $left = $this->left;
+
+        while ($left instanceof BinaryOperationExpression) {
+            $left = $left->left;
+        }
+
+        $right = $this->right;
+
+        while ($right instanceof BinaryOperationExpression) {
+            $right = $right->right;
+        }
+
+        $leftSpan = $left->getSpan();
+        $rightSpan = $right->getSpan();
+
+        return $leftSpan->expand($rightSpan);
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitBinaryOperationExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '';
+
+        $leftNeedsParens = $this->left instanceof BinaryOperationExpression && BinaryOperator::getPrecedence($this->left->getOperator()) < BinaryOperator::getPrecedence($this->operator);
+        if ($leftNeedsParens) {
+            $buffer .= '(';
+        }
+        $buffer .= $this->left;
+        if ($leftNeedsParens) {
+            $buffer .= ')';
+        }
+
+        $buffer .= ' ';
+        $buffer .= $this->operator;
+        $buffer .= ' ';
+
+        $rightNeedsParens = $this->right instanceof BinaryOperationExpression && BinaryOperator::getPrecedence($this->right->getOperator()) <= BinaryOperator::getPrecedence($this->operator);
+        if ($rightNeedsParens) {
+            $buffer .= '(';
+        }
+        $buffer .= $this->right;
+        if ($rightNeedsParens) {
+            $buffer .= ')';
+        }
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/BinaryOperator.php

@@ -0,0 +1,72 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+/**
+ * @internal
+ */
+final class BinaryOperator
+{
+    const SINGLE_EQUALS = '=';
+    const OR = 'or';
+    const AND = 'and';
+    const EQUALS = '==';
+    const NOT_EQUALS = '!=';
+    const GREATER_THAN = '>';
+    const GREATER_THAN_OR_EQUALS = '>=';
+    const LESS_THAN = '<';
+    const LESS_THAN_OR_EQUALS = '<=';
+    const PLUS = '+';
+    const MINUS = '-';
+    const TIMES = '*';
+    const DIVIDED_BY = '/';
+    const MODULO = '%';
+
+    /**
+     * @param BinaryOperator::* $operator
+     */
+    public static function getPrecedence(string $operator): int
+    {
+        switch ($operator) {
+            case self::SINGLE_EQUALS:
+                return 0;
+
+            case self::OR:
+                return 1;
+
+            case self::AND:
+                return 2;
+
+            case self::EQUALS:
+            case self::NOT_EQUALS:
+                return 3;
+
+            case self::GREATER_THAN:
+            case self::GREATER_THAN_OR_EQUALS:
+            case self::LESS_THAN:
+            case self::LESS_THAN_OR_EQUALS:
+                return 4;
+
+            case self::PLUS:
+            case self::MINUS:
+                return 5;
+
+            case self::TIMES:
+            case self::DIVIDED_BY:
+            case self::MODULO:
+                return 6;
+        }
+
+        throw new \InvalidArgumentException(sprintf('Unknown operator "%s".', $operator));
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/BooleanExpression.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A boolean literal, `true` or `false`.
+ *
+ * @internal
+ */
+final class BooleanExpression implements Expression
+{
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(bool $value, FileSpan $span)
+    {
+        $this->value = $value;
+        $this->span = $span;
+    }
+
+    public function getValue(): bool
+    {
+        return $this->value;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitBooleanExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return $this->value ? 'true' : 'false';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/CalculationExpression.php

@@ -0,0 +1,235 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A calculation literal.
+ *
+ * @internal
+ */
+final class CalculationExpression implements Expression
+{
+    /**
+     * This calculation's name.
+     *
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * The arguments for the calculation.
+     *
+     * @var list<Expression>
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * Returns a `calc()` calculation expression.
+     *
+     * @param Expression $argument
+     * @param FileSpan   $span
+     *
+     * @return CalculationExpression
+     */
+    public static function calc(Expression $argument, FileSpan $span): CalculationExpression
+    {
+        return new CalculationExpression('calc', [$argument], $span);
+    }
+
+    /**
+     * Returns a `min()` calculation expression.
+     *
+     * @param list<Expression> $arguments
+     * @param FileSpan         $span
+     *
+     * @return CalculationExpression
+     */
+    public static function min(array $arguments, FileSpan $span): CalculationExpression
+    {
+        if (!$arguments) {
+            throw new \InvalidArgumentException('min() requires at least one argument.');
+        }
+
+        return new CalculationExpression('min', $arguments, $span);
+    }
+
+    /**
+     * Returns a `max()` calculation expression.
+     *
+     * @param list<Expression> $arguments
+     * @param FileSpan         $span
+     *
+     * @return CalculationExpression
+     */
+    public static function max(array $arguments, FileSpan $span): CalculationExpression
+    {
+        if (!$arguments) {
+            throw new \InvalidArgumentException('max() requires at least one argument.');
+        }
+
+        return new CalculationExpression('max', $arguments, $span);
+    }
+
+    /**
+     * Returns a `clamp()` calculation expression.
+     *
+     * @param Expression $min
+     * @param Expression $value
+     * @param Expression $max
+     * @param FileSpan   $span
+     *
+     * @return CalculationExpression
+     */
+    public static function clamp(Expression $min, Expression $value, Expression $max, FileSpan $span): CalculationExpression
+    {
+        return new CalculationExpression('clamp', [$min, $value, $max], $span);
+    }
+
+    /**
+     * Returns a calculation expression with the given name and arguments.
+     *
+     * Unlike the other constructors, this doesn't verify that the arguments are
+     * valid for the name.
+     *
+     * @param string           $name
+     * @param list<Expression> $arguments
+     * @param FileSpan         $span
+     */
+    public function __construct(string $name, array $arguments, FileSpan $span)
+    {
+        self::verifyArguments($arguments);
+        $this->name = $name;
+        $this->arguments = $arguments;
+        $this->span = $span;
+    }
+
+    /**
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * @return list<Expression>
+     */
+    public function getArguments(): array
+    {
+        return $this->arguments;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitCalculationExpression($this);
+    }
+
+    /**
+     * @param list<Expression> $arguments
+     *
+     * @throws \InvalidArgumentException if $arguments aren't valid calculation arguments.
+     */
+    private static function verifyArguments(array $arguments): void
+    {
+        foreach ($arguments as $argument) {
+            self::verify($argument);
+        }
+    }
+
+    /**
+     * @throws \InvalidArgumentException if $expression isn't a valid calculation argument.
+     */
+    private static function verify(Expression $expression): void
+    {
+        if ($expression instanceof NumberExpression) {
+            return;
+        }
+
+        if ($expression instanceof CalculationExpression) {
+            return;
+        }
+
+        if ($expression instanceof VariableExpression) {
+            return;
+        }
+
+        if ($expression instanceof FunctionExpression) {
+            return;
+        }
+
+        if ($expression instanceof IfExpression) {
+            return;
+        }
+
+        if ($expression instanceof StringExpression) {
+            if ($expression->hasQuotes()) {
+                throw new \InvalidArgumentException('Invalid calculation argument.');
+            }
+
+            return;
+        }
+
+        if ($expression instanceof ParenthesizedExpression) {
+            self::verify($expression->getExpression());
+
+            return;
+        }
+
+        if ($expression instanceof BinaryOperationExpression) {
+            self::verify($expression->getLeft());
+            self::verify($expression->getRight());
+
+            if ($expression->getOperator() === BinaryOperator::PLUS) {
+                return;
+            }
+
+            if ($expression->getOperator() === BinaryOperator::MINUS) {
+                return;
+            }
+
+            if ($expression->getOperator() === BinaryOperator::TIMES) {
+                return;
+            }
+
+            if ($expression->getOperator() === BinaryOperator::DIVIDED_BY) {
+                return;
+            }
+
+            throw new \InvalidArgumentException('Invalid calculation argument.');
+        }
+
+        throw new \InvalidArgumentException('Invalid calculation argument.');
+    }
+
+    public function __toString(): string
+    {
+        return $this->name . '(' . implode(', ', $this->arguments) . ')';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/ColorExpression.php

@@ -0,0 +1,64 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Value\SassColor;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A color literal.
+ *
+ * @internal
+ */
+final class ColorExpression implements Expression
+{
+    /**
+     * @var SassColor
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(SassColor $value, FileSpan $span)
+    {
+        $this->value = $value;
+        $this->span = $span;
+    }
+
+    public function getValue(): SassColor
+    {
+        return $this->value;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitColorExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return (string) $this->value;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/FunctionExpression.php

@@ -0,0 +1,141 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\CallableInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\SassReference;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A function invocation.
+ *
+ * This may be a plain CSS function or a Sass function,  but may not include
+ * interpolation.
+ *
+ * @internal
+ */
+final class FunctionExpression implements Expression, CallableInvocation, SassReference
+{
+    /**
+     * The name of the function being invoked, with underscores left as-is.
+     *
+     * @var string
+     * @readonly
+     */
+    private $originalName;
+
+    /**
+     * The arguments to pass to the function.
+     *
+     * @var ArgumentInvocation
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * The namespace of the function being invoked, or `null` if it's invoked
+     * without a namespace.
+     *
+     * @var string|null
+     * @readonly
+     */
+    private $namespace;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $originalName, ArgumentInvocation $arguments, FileSpan $span, ?string $namespace = null)
+    {
+        $this->span = $span;
+        $this->originalName = $originalName;
+        $this->arguments = $arguments;
+        $this->namespace = $namespace;
+    }
+
+    /**
+     * @return string
+     */
+    public function getOriginalName(): string
+    {
+        return $this->originalName;
+    }
+
+    /**
+     * The name of the function being invoked, with underscores converted to
+     * hyphens.
+     *
+     * If this function is a plain CSS function, use {@see getOriginalName} instead.
+     */
+    public function getName(): string
+    {
+        return str_replace('_', '-', $this->originalName);
+    }
+
+    public function getArguments(): ArgumentInvocation
+    {
+        return $this->arguments;
+    }
+
+    public function getNamespace(): ?string
+    {
+        return $this->namespace;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        if ($this->namespace === null) {
+            return SpanUtil::initialIdentifier($this->span);
+        }
+
+        return SpanUtil::initialIdentifier(SpanUtil::withoutNamespace($this->span));
+    }
+
+    public function getNamespaceSpan(): ?FileSpan
+    {
+        if ($this->namespace === null) {
+            return null;
+        }
+
+        return SpanUtil::initialIdentifier($this->span);
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitFunctionExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '';
+
+        if ($this->namespace !== null) {
+            $buffer .= $this->namespace . '.';
+        }
+
+        $buffer .= $this->originalName . $this->arguments;
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/IfExpression.php

@@ -0,0 +1,89 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentDeclaration;
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\CallableInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A ternary expression.
+ *
+ * This is defined as a separate syntactic construct rather than a normal
+ * function because only one of the `$if-true` and `$if-false` arguments are
+ * evaluated.
+ *
+ * @internal
+ */
+final class IfExpression implements Expression, CallableInvocation
+{
+    /**
+     * The arguments passed to `if()`.
+     *
+     * @var ArgumentInvocation
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @var ArgumentDeclaration|null
+     */
+    private static $declaration;
+
+    public function __construct(ArgumentInvocation $arguments, FileSpan $span)
+    {
+        $this->span = $span;
+        $this->arguments = $arguments;
+    }
+
+    /**
+     * The declaration of `if()`, as though it were a normal function.
+     */
+    public static function getDeclaration(): ArgumentDeclaration
+    {
+        if (self::$declaration === null) {
+            self::$declaration = ArgumentDeclaration::parse('@function if($condition, $if-true, $if-false) {');
+        }
+
+        return self::$declaration;
+    }
+
+    public function getArguments(): ArgumentInvocation
+    {
+        return $this->arguments;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitIfExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return 'if' . $this->arguments;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/InterpolatedFunctionExpression.php

@@ -0,0 +1,84 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\CallableInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * An interpolated function invocation.
+ *
+ * This is always a plain CSS function.
+ *
+ * @internal
+ */
+final class InterpolatedFunctionExpression implements Expression, CallableInvocation
+{
+    /**
+     * The name of the function being invoked.
+     *
+     * @var Interpolation
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * The arguments to pass to the function.
+     *
+     * @var ArgumentInvocation
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Interpolation $name, ArgumentInvocation $arguments, FileSpan $span)
+    {
+        $this->span = $span;
+        $this->name = $name;
+        $this->arguments = $arguments;
+    }
+
+    public function getName(): Interpolation
+    {
+        return $this->name;
+    }
+
+    public function getArguments(): ArgumentInvocation
+    {
+        return $this->arguments;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitInterpolatedFunctionExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return $this->name . $this->arguments;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/ListExpression.php

@@ -0,0 +1,142 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Value\ListSeparator;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A list literal.
+ *
+ * @internal
+ */
+final class ListExpression implements Expression
+{
+    /**
+     * @var Expression[]
+     * @readonly
+     */
+    private $contents;
+
+    /**
+     * @var ListSeparator::*
+     * @readonly
+     */
+    private $separator;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $brackets;
+
+    /**
+     * ListExpression constructor.
+     *
+     * @param Expression[] $contents
+     * @param ListSeparator::* $separator
+     */
+    public function __construct(array $contents, string $separator, FileSpan $span, bool $brackets = false)
+    {
+        $this->contents = $contents;
+        $this->separator = $separator;
+        $this->span = $span;
+        $this->brackets = $brackets;
+    }
+
+    /**
+     * @return Expression[]
+     */
+    public function getContents(): array
+    {
+        return $this->contents;
+    }
+
+    /**
+     * @return ListSeparator::*
+     */
+    public function getSeparator(): string
+    {
+        return $this->separator;
+    }
+
+    public function hasBrackets(): bool
+    {
+        return $this->brackets;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitListExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '';
+        if ($this->hasBrackets()) {
+            $buffer .= '[';
+        }
+
+        $buffer .= implode($this->separator === ListSeparator::COMMA ? ', ' : ' ', array_map(function ($element) {
+            return $this->elementNeedsParens($element) ? "($element)" : (string) $element;
+        }, $this->contents));
+
+        if ($this->hasBrackets()) {
+            $buffer .= ']';
+        }
+
+        return $buffer;
+    }
+
+    /**
+     * Returns whether $expression, contained in $this, needs parentheses when
+     * printed as Sass source.
+     */
+    private function elementNeedsParens(Expression $expression): bool
+    {
+        if ($expression instanceof ListExpression) {
+            if (\count($expression->contents) < 2) {
+                return false;
+            }
+
+            if ($expression->brackets) {
+                return false;
+            }
+
+            return $this->separator === ListSeparator::COMMA ? $expression->separator === ListSeparator::COMMA : $expression->separator !== ListSeparator::UNDECIDED;
+        }
+
+        if ($this->separator !== ListSeparator::SPACE) {
+            return false;
+        }
+
+        if ($expression instanceof UnaryOperationExpression) {
+            return $expression->getOperator() === UnaryOperator::PLUS || $expression->getOperator() === UnaryOperator::MINUS;
+        }
+
+        return false;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/MapExpression.php

@@ -0,0 +1,71 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A map literal.
+ *
+ * @internal
+ */
+final class MapExpression implements Expression
+{
+    /**
+     * @var list<array{Expression, Expression}>
+     * @readonly
+     */
+    private $pairs;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param list<array{Expression, Expression}> $pairs
+     */
+    public function __construct(array $pairs, FileSpan $span)
+    {
+        $this->pairs = $pairs;
+        $this->span = $span;
+    }
+
+    /**
+     * @return list<array{Expression, Expression}>
+     */
+    public function getPairs(): array
+    {
+        return $this->pairs;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitMapExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return '(' . implode(', ', array_map(function ($pair) {
+            return $pair[0] . ': ' . $pair[1];
+        }, $this->pairs)) . ')';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/NullExpression.php

@@ -0,0 +1,51 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A null literal.
+ *
+ * @internal
+ */
+final class NullExpression implements Expression
+{
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(FileSpan $span)
+    {
+        $this->span = $span;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitNullExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return 'null';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/NumberExpression.php

@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Value\SassNumber;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A number literal.
+ *
+ * @internal
+ */
+final class NumberExpression implements Expression
+{
+    /**
+     * @var float
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @var string|null
+     * @readonly
+     */
+    private $unit;
+
+    public function __construct(float $value, FileSpan $span, ?string $unit = null)
+    {
+        $this->value = $value;
+        $this->span = $span;
+        $this->unit = $unit;
+    }
+
+    public function getValue(): float
+    {
+        return $this->value;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function getUnit(): ?string
+    {
+        return $this->unit;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitNumberExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return (string) SassNumber::create($this->value, $this->unit);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/ParenthesizedExpression.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * An expression wrapped in parentheses.
+ *
+ * @internal
+ */
+final class ParenthesizedExpression implements Expression
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Expression $expression, FileSpan $span)
+    {
+        $this->expression = $expression;
+        $this->span = $span;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitParenthesizedExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return '(' . $this->expression . ')';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/SelectorExpression.php

@@ -0,0 +1,51 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A parent selector reference, `&`.
+ *
+ * @internal
+ */
+final class SelectorExpression implements Expression
+{
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(FileSpan $span)
+    {
+        $this->span = $span;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitSelectorExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return '&';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/StringExpression.php

@@ -0,0 +1,182 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Parser\InterpolationBuffer;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\Character;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A string literal.
+ *
+ * @internal
+ */
+final class StringExpression implements Expression
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $text;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $quotes;
+
+    public function __construct(Interpolation $text, bool $quotes = false)
+    {
+        $this->text = $text;
+        $this->quotes = $quotes;
+    }
+
+    /**
+     * Returns a string expression with no interpolation.
+     */
+    public static function plain(string $text, FileSpan $span, bool $quotes = false): self
+    {
+        return new self(new Interpolation([$text], $span), $quotes);
+    }
+
+    /**
+     * Returns Sass source for a quoted string that, when evaluated, will have
+     * $text as its contents.
+     */
+    public static function quoteText(string $text): string
+    {
+        $quote = self::bestQuote([$text]);
+        $buffer = $quote;
+        $buffer .= self::quoteInnerText($text, $quote, true);
+        $buffer .= $quote;
+
+        return $buffer;
+    }
+
+    public function getText(): Interpolation
+    {
+        return $this->text;
+    }
+
+    public function hasQuotes(): bool
+    {
+        return $this->quotes;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->text->getSpan();
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitStringExpression($this);
+    }
+
+    public function asInterpolation(bool $static = false, string $quote = null): Interpolation
+    {
+        if (!$this->quotes) {
+            return $this->text;
+        }
+
+        $quote = $quote ?? self::bestQuote($this->text->getContents());
+        $buffer = new InterpolationBuffer();
+
+        $buffer->write($quote);
+
+        foreach ($this->text->getContents() as $value) {
+            if ($value instanceof Expression) {
+                $buffer->add($value);
+            } else {
+                $buffer->write(self::quoteInnerText($value, $quote, $static));
+            }
+        }
+
+        $buffer->write($quote);
+
+        return $buffer->buildInterpolation($this->text->getSpan());
+    }
+
+    private static function quoteInnerText(string $value, string $quote, bool $static = false): string
+    {
+        $buffer = '';
+        $length = \strlen($value);
+
+        for ($i = 0; $i < $length; $i++) {
+            $char = $value[$i];
+
+            if (Character::isNewline($char)) {
+                $buffer .= '\\a';
+
+                if ($i !== $length - 1) {
+                    $next = $value[$i + 1];
+
+                    if (Character::isWhitespace($next) || Character::isHex($next)) {
+                        $buffer .= ' ';
+                    }
+                }
+            } else {
+                if ($char === $quote || $char === '\\' || ($static && $char === '#' && $i < $length - 1 && $value[$i + 1] === '{')) {
+                    $buffer .= '\\';
+                }
+
+                if (\ord($char) < 0x80) {
+                    $buffer .= $char;
+                } else {
+                    if (!preg_match('/./usA', $value, $m, 0, $i)) {
+                        throw new \UnexpectedValueException('Invalid UTF-8 char');
+                    }
+
+                    $buffer .= $m[0];
+                    $i += \strlen($m[0]) - 1; // skip over the extra bytes that have been processed.
+                }
+            }
+        }
+
+        return $buffer;
+    }
+
+    /**
+     * @param array<string|Expression> $parts
+     *
+     * @return string
+     */
+    private static function bestQuote(array $parts): string
+    {
+        $containsDoubleQuote = false;
+
+        foreach ($parts as $part) {
+            if (!\is_string($part)) {
+                continue;
+            }
+
+            if (false !== strpos($part, "'")) {
+                return '"';
+            }
+
+            if (false !== strpos($part, '"')) {
+                $containsDoubleQuote = true;
+            }
+        }
+
+        return $containsDoubleQuote ? "'": '"';
+    }
+
+    public function __toString(): string
+    {
+        return (string) $this->asInterpolation();
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/SupportsExpression.php

@@ -0,0 +1,60 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\SupportsCondition;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * An expression-level `@supports` condition.
+ *
+ * This appears only in the modifiers that come after a plain-CSS `@import`. It
+ * doesn't include the function name wrapping the condition.
+ *
+ * @internal
+ */
+final class SupportsExpression implements Expression
+{
+    /**
+     * @var SupportsCondition
+     * @readonly
+     */
+    private $condition;
+
+    public function __construct(SupportsCondition $condition)
+    {
+        $this->condition = $condition;
+    }
+
+    public function getCondition(): SupportsCondition
+    {
+        return $this->condition;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->condition->getSpan();
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitSupportsExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return (string) $this->condition;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/UnaryOperationExpression.php

@@ -0,0 +1,87 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A unary operator, as in `+$var` or `not fn()`.
+ *
+ * @internal
+ */
+final class UnaryOperationExpression implements Expression
+{
+    /**
+     * @var UnaryOperator::*
+     * @readonly
+     */
+    private $operator;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $operand;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param UnaryOperator::* $operator
+     */
+    public function __construct(string $operator, Expression $operand, FileSpan $span)
+    {
+        $this->operator = $operator;
+        $this->operand = $operand;
+        $this->span = $span;
+    }
+
+    /**
+     * @return UnaryOperator::*
+     */
+    public function getOperator()
+    {
+        return $this->operator;
+    }
+
+    public function getOperand(): Expression
+    {
+        return $this->operand;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitUnaryOperationExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = $this->operator;
+        if ($this->operator === UnaryOperator::NOT) {
+            $buffer .= ' ';
+        }
+        $buffer .= $this->operand;
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/UnaryOperator.php

@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+/**
+ * @internal
+ */
+final class UnaryOperator
+{
+    const PLUS = '+';
+    const MINUS = '-';
+    const DIVIDE = '/';
+    const NOT = 'not';
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/ValueExpression.php

@@ -0,0 +1,67 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Value\Value;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * An expression that directly embeds a value.
+ *
+ * This is never constructed by the parser. It's only used when ASTs are
+ * constructed dynamically, as for the `call()` function.
+ *
+ * @internal
+ */
+final class ValueExpression implements Expression
+{
+    /**
+     * @var Value
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Value $value, FileSpan $span)
+    {
+        $this->value = $value;
+        $this->span = $span;
+    }
+
+    public function getValue(): Value
+    {
+        return $this->value;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitValueExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        return (string) $this->value;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Expression/VariableExpression.php

@@ -0,0 +1,104 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Expression;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\SassReference;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+use ScssPhp\ScssPhp\Visitor\ExpressionVisitor;
+
+/**
+ * A Sass variable.
+ *
+ * @internal
+ */
+final class VariableExpression implements Expression, SassReference
+{
+    /**
+     * The name of this variable, with underscores converted to hyphens.
+     *
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * The namespace of the variable being referenced, or `null` if it's
+     * referenced without a namespace.
+     *
+     * @var string|null
+     * @readonly
+     */
+    private $namespace;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $name, FileSpan $span, ?string $namespace = null)
+    {
+        $this->span = $span;
+        $this->name = $name;
+        $this->namespace = $namespace;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function getNamespace(): ?string
+    {
+        return $this->namespace;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        if ($this->namespace === null) {
+            return $this->span;
+        }
+
+        return SpanUtil::withoutNamespace($this->span);
+    }
+
+    public function getNamespaceSpan(): ?FileSpan
+    {
+        if ($this->namespace === null) {
+            return null;
+        }
+
+        return SpanUtil::initialIdentifier($this->span);
+    }
+
+    public function accept(ExpressionVisitor $visitor)
+    {
+        return $visitor->visitVariableExpression($this);
+    }
+
+    public function __toString(): string
+    {
+        if ($this->namespace === null) {
+            return '$' . $this->name;
+        }
+
+        return $this->namespace . '$' . $this->name;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Import.php

@@ -0,0 +1,22 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+/**
+ * An interface for different types of import.
+ *
+ * @internal
+ */
+interface Import extends SassNode
+{
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Import/DynamicImport.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Import;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression\StringExpression;
+use ScssPhp\ScssPhp\Ast\Sass\Import;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * An import that will load a Sass file at runtime.
+ *
+ * @internal
+ */
+final class DynamicImport implements Import
+{
+    /**
+     * The URI of the file to import.
+     *
+     * If this is relative, it's relative to the containing file.
+     *
+     * @var string
+     * @readonly
+     */
+    private $urlString;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $urlString, FileSpan $span)
+    {
+        $this->urlString = $urlString;
+        $this->span = $span;
+    }
+
+    public function getUrlString(): string
+    {
+        return $this->urlString;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function __toString(): string
+    {
+        return StringExpression::quoteText($this->urlString);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Import/StaticImport.php

@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Import;
+
+use ScssPhp\ScssPhp\Ast\Sass\Import;
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * An import that produces a plain CSS `@import` rule.
+ *
+ * @internal
+ */
+final class StaticImport implements Import
+{
+    /**
+     * The URL for this import.
+     *
+     * This already contains quotes.
+     *
+     * @var Interpolation
+     * @readonly
+     */
+    private $url;
+
+    /**
+     * The modifiers (such as media or supports queries) attached to this import,
+     * or `null` if none are attached.
+     *
+     * @var Interpolation|null
+     * @readonly
+     */
+    private $modifiers;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Interpolation $url, FileSpan $span, ?Interpolation $modifiers = null)
+    {
+        $this->url = $url;
+        $this->span = $span;
+        $this->modifiers = $modifiers;
+    }
+
+    public function getUrl(): Interpolation
+    {
+        return $this->url;
+    }
+
+    public function getModifiers(): ?Interpolation
+    {
+        return $this->modifiers;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function __toString(): string
+    {
+        $buffer = (string) $this->url;
+
+        if ($this->modifiers !== null) {
+            $buffer .= ' ' . $this->modifiers;
+        }
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Interpolation.php

@@ -0,0 +1,138 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\Parser\InterpolationBuffer;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * Plain text interpolated with Sass expressions.
+ *
+ * @internal
+ */
+final class Interpolation implements SassNode
+{
+    /**
+     * @var list<string|Expression>
+     * @readonly
+     */
+    private $contents;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * Creates a new {@see Interpolation} by concatenating a sequence of strings,
+     * {@see Expression}s, or nested {@see Interpolation}s.
+     *
+     * @param array<string|Expression|Interpolation> $contents
+     */
+    public static function concat(array $contents, FileSpan $span): Interpolation
+    {
+        $buffer = new InterpolationBuffer();
+
+        foreach ($contents as $element) {
+            if (\is_string($element)) {
+                $buffer->write($element);
+            } elseif ($element instanceof Expression) {
+                $buffer->add($element);
+            } elseif ($element instanceof Interpolation) {
+                $buffer->addInterpolation($element);
+            } else {
+                throw new \InvalidArgumentException(sprintf('The elements in $contents may only contains strings, Expressions, or Interpolations, "%s" given.', \is_object($element) ? get_class($element) : gettype($element)));
+            }
+        }
+
+        return $buffer->buildInterpolation($span);
+    }
+
+    /**
+     * @param list<string|Expression> $contents
+     */
+    public function __construct(array $contents, FileSpan $span)
+    {
+        for ($i = 0; $i < \count($contents); $i++) {
+            if (!\is_string($contents[$i]) && !$contents[$i] instanceof Expression) {
+                throw new \TypeError('The contents of an Interpolation may only contain strings or Expression instances.');
+            }
+
+            if ($i != 0 && \is_string($contents[$i]) && \is_string($contents[$i - 1])) {
+                throw new \InvalidArgumentException('The contents of an Interpolation may not contain adjacent strings.');
+            }
+        }
+
+        $this->contents = $contents;
+        $this->span = $span;
+    }
+
+    /**
+     * @return list<string|Expression>
+     */
+    public function getContents(): array
+    {
+        return $this->contents;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    /**
+     * If this contains no interpolated expressions, returns its text contents.
+     *
+     * Otherwise, returns `null`.
+     *
+     * @psalm-mutation-free
+     */
+    public function getAsPlain(): ?string
+    {
+        if (\count($this->contents) === 0) {
+            return '';
+        }
+
+        if (\count($this->contents) > 1) {
+            return null;
+        }
+
+        if (\is_string($this->contents[0])) {
+            return $this->contents[0];
+        }
+
+        return null;
+    }
+
+    /**
+     * Returns the plain text before the interpolation, or the empty string.
+     */
+    public function getInitialPlain(): string
+    {
+        $first = $this->contents[0] ?? null;
+
+        if (\is_string($first)) {
+            return $first;
+        }
+
+        return '';
+    }
+
+    public function __toString(): string
+    {
+        return implode('', array_map(function ($value) {
+            return \is_string($value) ? $value : '#{' . $value .'}';
+        }, $this->contents));
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/SassDeclaration.php

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A common interface for any node that declares a Sass member.
+ *
+ * @internal
+ */
+interface SassDeclaration extends SassNode
+{
+    /**
+     * The name of the declaration, with underscores converted to hyphens.
+     *
+     * This does not include the `$` for variables.
+     */
+    public function getName(): string;
+
+    /**
+     * The span containing this declaration's name.
+     *
+     * This includes the `$` for variables.
+     */
+    public function getNameSpan(): FileSpan;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/SassNode.php

@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\Ast\AstNode;
+
+/**
+ * A node in the abstract syntax tree for an unevaluated Sass file.
+ *
+ * @internal
+ */
+interface SassNode extends AstNode
+{
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/SassReference.php

@@ -0,0 +1,50 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * A common interface for any node that references a Sass member.
+ *
+ * @internal
+ */
+interface SassReference extends SassNode
+{
+    /**
+     * The namespace of the member being referenced, or `null` if it's referenced
+     * without a namespace.
+     */
+    public function getNamespace(): ?string;
+
+    /**
+     * The name of the member being referenced, with underscores converted to
+     * hyphens.
+     *
+     * This does not include the `$` for variables.
+     */
+    public function getName(): string;
+
+    /**
+     * The span containing this reference's name.
+     *
+     * For variables, this should include the `$`.
+     */
+    public function getNameSpan(): FileSpan;
+
+    /**
+     * The span containing this reference's namespace, null if {@see getNamespace} is
+     * null.
+     */
+    public function getNamespaceSpan(): ?FileSpan;
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass;
+
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A statement in a Sass syntax tree.
+ *
+ * @internal
+ */
+interface Statement extends SassNode
+{
+    /**
+     * @template T
+     * @param StatementVisitor<T> $visitor
+     * @return T
+     */
+    public function accept(StatementVisitor $visitor);
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/AtRootRule.php

@@ -0,0 +1,80 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@at-root` rule.
+ *
+ * This moves it contents "up" the tree through parent nodes.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class AtRootRule extends ParentStatement
+{
+    /**
+     * @var Interpolation|null
+     * @readonly
+     */
+    private $query;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(array $children, FileSpan $span, ?Interpolation $query = null)
+    {
+        $this->query = $query;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    /**
+     * The query specifying which statements this should move its contents through.
+     */
+    public function getQuery(): ?Interpolation
+    {
+        return $this->query;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitAtRootRule($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '@at-root ';
+        if ($this->query !== null) {
+            $buffer .= $this->query . ' ';
+        }
+
+        return $buffer . '{' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/AtRule.php

@@ -0,0 +1,93 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * An unknown at-rule.
+ *
+ * @extends ParentStatement<Statement[]|null>
+ *
+ * @internal
+ */
+final class AtRule extends ParentStatement
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var Interpolation|null
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[]|null $children
+     */
+    public function __construct(Interpolation $name, FileSpan $span, ?Interpolation $value = null, ?array $children = null)
+    {
+        $this->name = $name;
+        $this->value = $value;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    public function getName(): Interpolation
+    {
+        return $this->name;
+    }
+
+    public function getValue(): ?Interpolation
+    {
+        return $this->value;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitAtRule($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '@' . $this->name;
+        if ($this->value !== null) {
+            $buffer .= ' ' . $this->value;
+        }
+
+        $children = $this->getChildren();
+
+        if ($children === null) {
+            return $buffer . ';';
+        }
+
+        return $buffer . '{' . implode(' ', $children) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/CallableDeclaration.php

@@ -0,0 +1,90 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentDeclaration;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+
+/**
+ * An abstract class for callables (functions or mixins) that are declared in
+ * user code.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+abstract class CallableDeclaration extends ParentStatement
+{
+    /**
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var ArgumentDeclaration
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var SilentComment|null
+     * @readonly
+     */
+    private $comment;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(string $name, ArgumentDeclaration $arguments, FileSpan $span, array $children, ?SilentComment $comment = null)
+    {
+        $this->name = $name;
+        $this->arguments = $arguments;
+        $this->comment = $comment;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    /**
+     * The name of this callable, with underscores converted to hyphens.
+     */
+    final public function getName(): string
+    {
+        return $this->name;
+    }
+
+    final public function getArguments(): ArgumentDeclaration
+    {
+        return $this->arguments;
+    }
+
+    /**
+     * @return SilentComment|null
+     */
+    final public function getComment(): ?SilentComment
+    {
+        return $this->comment;
+    }
+
+    final public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ContentBlock.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentDeclaration;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * An anonymous block of code that's invoked for a {@see ContentRule}.
+ *
+ * @internal
+ */
+final class ContentBlock extends CallableDeclaration
+{
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(ArgumentDeclaration $arguments, array $children, FileSpan $span)
+    {
+        parent::__construct('@content', $arguments, $span, $children);
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitContentBlock($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = $this->getArguments()->isEmpty() ? '' : ' using (' . $this->getArguments() . ')';
+
+        return $buffer . '{' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ContentRule.php

@@ -0,0 +1,71 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@content` rule.
+ *
+ * This is used in a mixin to include statement-level content passed by the
+ * caller.
+ *
+ * @internal
+ */
+final class ContentRule implements Statement
+{
+    /**
+     * The arguments pass to this `@content` rule.
+     *
+     * This will be an empty invocation if `@content` has no arguments.
+     *
+     * @var ArgumentInvocation
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(ArgumentInvocation $arguments, FileSpan $span)
+    {
+        $this->arguments = $arguments;
+        $this->span = $span;
+    }
+
+    public function getArguments(): ArgumentInvocation
+    {
+        return $this->arguments;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitContentRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return $this->arguments->isEmpty() ? '@content;' : "@content($this->arguments);";
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/DebugRule.php

@@ -0,0 +1,66 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@debug` rule.
+ *
+ * This prints a Sass value for debugging purposes.
+ *
+ * @internal
+ */
+final class DebugRule implements Statement
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Expression $expression, FileSpan $span)
+    {
+        $this->expression = $expression;
+        $this->span = $span;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitDebugRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@debug ' . $this->expression . ';';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/Declaration.php

@@ -0,0 +1,143 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Expression\StringExpression;
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A declaration (that is, a `name: value` pair).
+ *
+ * @extends ParentStatement<Statement[]|null>
+ *
+ * @internal
+ */
+final class Declaration extends ParentStatement
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * The value of this declaration.
+     *
+     * If {@see getChildren} is `null`, this is never `null`. Otherwise, it may or may
+     * not be `null`.
+     *
+     * @var Expression|null
+     * @readonly
+     */
+    private $value;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[]|null $children
+     */
+    private function __construct(Interpolation $name, ?Expression $value, FileSpan $span, ?array $children = null)
+    {
+        $this->name = $name;
+        $this->value = $value;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    public static function create(Interpolation $name, Expression $value, FileSpan $span): self
+    {
+        $declaration = new self($name, $value, $span);
+
+        if ($declaration->isCustomProperty() && !$value instanceof StringExpression) {
+            throw new \InvalidArgumentException(sprintf('Declarations whose names begin with "--" must have StringExpression values (got %s)', get_class($value)));
+        }
+
+        return $declaration;
+    }
+
+    /**
+     * @param Statement[] $children
+     */
+    public static function nested(Interpolation $name, array $children, FileSpan $span, ?Expression $value = null): self
+    {
+        $declaration = new self($name, $value, $span, $children);
+
+        if ($declaration->isCustomProperty() && !$value instanceof StringExpression) {
+            throw new \InvalidArgumentException('Declarations whose names begin with "--" may not be nested.');
+        }
+
+        return $declaration;
+    }
+
+    public function getName(): Interpolation
+    {
+        return $this->name;
+    }
+
+    public function getValue(): ?Expression
+    {
+        return $this->value;
+    }
+
+    /**
+     * Returns whether this is a CSS Custom Property declaration.
+     *
+     * Note that this can return `false` for declarations that will ultimately be
+     * serialized as custom properties if they aren't *parsed as* custom
+     * properties, such as `#{--foo}: ...`.
+     *
+     * If this is `true`, then `value` will be a {@see StringExpression}.
+     */
+    public function isCustomProperty(): bool
+    {
+        return 0 === strpos($this->name->getInitialPlain(), '--');
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitDeclaration($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = $this->name . ':';
+
+        if ($this->value !== null) {
+            if (!$this->isCustomProperty()) {
+                $buffer .= ' ';
+            }
+            $buffer .= $this->value;
+        }
+
+        $children = $this->getChildren();
+
+        if ($children === null) {
+            return $buffer . ';';
+        }
+
+        return $buffer . '{' . implode(' ', $children) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/EachRule.php

@@ -0,0 +1,88 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * An `@each` rule.
+ *
+ * This iterates over values in a list or map.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class EachRule extends ParentStatement
+{
+    /**
+     * @var string[]
+     * @readonly
+     */
+    private $variables;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $list;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param string[]    $variables
+     * @param Statement[] $children
+     */
+    public function __construct(array $variables, Expression $list, array $children, FileSpan $span)
+    {
+        $this->variables = $variables;
+        $this->list = $list;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getVariables(): array
+    {
+        return $this->variables;
+    }
+
+    public function getList(): Expression
+    {
+        return $this->list;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitEachRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@each ' . implode(', ', array_map(function ($variable) { return '$' . $variable; }, $this->variables)) . ' in ' . $this->list . ' {' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ElseClause.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+/**
+ * An `@else` clause in an `@if` rule.
+ *
+ * @internal
+ */
+final class ElseClause extends IfRuleClause
+{
+    public function __toString(): string
+    {
+        return '@else {' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ErrorRule.php

@@ -0,0 +1,66 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@error` rule.
+ *
+ * This emits an error and stops execution.
+ *
+ * @internal
+ */
+final class ErrorRule implements Statement
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Expression $expression, FileSpan $span)
+    {
+        $this->expression = $expression;
+        $this->span = $span;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitErrorRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@error ' . $this->expression . ';';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ExtendRule.php

@@ -0,0 +1,84 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * An `@extend` rule.
+ *
+ * This gives one selector all the styling of another.
+ *
+ * @internal
+ */
+final class ExtendRule implements Statement
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $selector;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $optional;
+
+    public function __construct(Interpolation $selector, FileSpan $span, bool $optional = false)
+    {
+        $this->selector = $selector;
+        $this->span = $span;
+        $this->optional = $optional;
+    }
+
+    public function getSelector(): Interpolation
+    {
+        return $this->selector;
+    }
+
+    /**
+     * Whether this is an optional extension.
+     *
+     * If an extension isn't optional, it will emit an error if it doesn't match
+     * any selectors.
+     */
+    public function isOptional(): bool
+    {
+        return $this->optional;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitExtendRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@extend ' . $this->selector . ($this->optional ? ' !optional' : '') . ';';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ForRule.php

@@ -0,0 +1,111 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@for` rule.
+ *
+ * This iterates a set number of times.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class ForRule extends ParentStatement
+{
+    /**
+     * @var string
+     * @readonly
+     */
+    private $variable;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $from;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $to;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $exclusive;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(string $variable, Expression $from, Expression $to, array $children, FileSpan $span, bool $exclusive = false)
+    {
+        $this->variable = $variable;
+        $this->from = $from;
+        $this->to = $to;
+        $this->exclusive = $exclusive;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    public function getVariable(): string
+    {
+        return $this->variable;
+    }
+
+    public function getFrom(): Expression
+    {
+        return $this->from;
+    }
+
+    public function getTo(): Expression
+    {
+        return $this->to;
+    }
+
+    /**
+     * Whether {@see getTo} is exclusive.
+     */
+    public function isExclusive(): bool
+    {
+        return $this->exclusive;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitForRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@for $' . $this->variable . ' from ' . $this->from . ($this->exclusive ? ' to ' : ' through ') . $this->to . '{' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/FunctionRule.php

@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\SassDeclaration;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A function declaration.
+ *
+ * This declares a function that's invoked using normal CSS function syntax.
+ *
+ * @internal
+ */
+final class FunctionRule extends CallableDeclaration implements SassDeclaration
+{
+    public function getNameSpan(): FileSpan
+    {
+        return SpanUtil::initialIdentifier(SpanUtil::withoutInitialAtRule($this->getSpan()));
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitFunctionRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@function ' . $this->getName() . '(' . $this->getArguments() . ') {' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/HasContentVisitor.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Visitor\StatementSearchVisitor;
+
+/**
+ * A visitor for determining whether a {@see MixinRule} recursively contains a
+ * {@see ContentRule}.
+ *
+ * @internal
+ *
+ * @extends StatementSearchVisitor<bool>
+ */
+final class HasContentVisitor extends StatementSearchVisitor
+{
+    public function visitContentRule(ContentRule $node): bool
+    {
+        return true;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/IfClause.php

@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+/**
+ * An `@if` or `@else if` clause in an `@if` rule.
+ *
+ * @internal
+ */
+final class IfClause extends IfRuleClause
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(Expression $expression, array $children)
+    {
+        $this->expression = $expression;
+        parent::__construct($children);
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/IfRule.php

@@ -0,0 +1,106 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * An `@if` rule.
+ *
+ * This conditionally executes a block of code.
+ *
+ * @internal
+ */
+final class IfRule implements Statement
+{
+    /**
+     * @var IfClause[]
+     * @readonly
+     */
+    private $clauses;
+
+    /**
+     * @var ElseClause|null
+     * @readonly
+     */
+    private $lastClause;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param IfClause[] $clauses
+     */
+    public function __construct(array $clauses, FileSpan $span, ?ElseClause $lastClause = null)
+    {
+        $this->clauses = $clauses;
+        $this->span = $span;
+        $this->lastClause = $lastClause;
+    }
+
+    /**
+     * The `@if` and `@else if` clauses.
+     *
+     * The first clause whose expression evaluates to `true` will have its
+     * statements executed. If no expression evaluates to `true`, `lastClause`
+     * will be executed if it's not `null`.
+     *
+     * @return IfClause[]
+     */
+    public function getClauses(): array
+    {
+        return $this->clauses;
+    }
+
+    /**
+     * The final, unconditional `@else` clause.
+     *
+     * This is `null` if there is no unconditional `@else`.
+     *
+     * @return ElseClause|null
+     */
+    public function getLastClause(): ?ElseClause
+    {
+        return $this->lastClause;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitIfRule($this);
+    }
+
+    public function __toString(): string
+    {
+        $parts = [];
+
+        foreach ($this->clauses as $index => $clause) {
+            $parts[] = ($index === 0 ? '@if ' : '@else if ') . $clause->getExpression() . '{' . implode(' ', $clause->getChildren()) . '}';
+        }
+
+        if ($this->lastClause !== null) {
+            $parts[] = $this->lastClause;
+        }
+
+        return implode(' ', $parts);
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/IfRuleClause.php

@@ -0,0 +1,73 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Import\DynamicImport;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+/**
+ * The superclass of `@if` and `@else` clauses.
+ *
+ * @internal
+ */
+abstract class IfRuleClause
+{
+    /**
+     * @var Statement[]
+     * @readonly
+     */
+    private $children;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $declarations = false;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(array $children)
+    {
+        $this->children = $children;
+
+        foreach ($children as $child) {
+            if ($child instanceof VariableDeclaration || $child instanceof FunctionRule || $child instanceof MixinRule) {
+                $this->declarations = true;
+                break;
+            }
+
+            if ($child instanceof ImportRule) {
+                foreach ($child->getImports() as $import) {
+                    if ($import instanceof DynamicImport) {
+                        $this->declarations = true;
+                        break 2;
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * @return Statement[]
+     */
+    final public function getChildren(): array
+    {
+        return $this->children;
+    }
+
+    final public function hasDeclarations(): bool
+    {
+        return $this->declarations;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ImportRule.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Import;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * An `@import` rule.
+ *
+ * @internal
+ */
+final class ImportRule implements Statement
+{
+    /**
+     * @var Import[]
+     * @readonly
+     */
+    private $imports;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Import[] $imports
+     */
+    public function __construct(array $imports, FileSpan $span)
+    {
+        $this->imports = $imports;
+        $this->span = $span;
+    }
+
+    /**
+     * @return Import[]
+     */
+    public function getImports(): array
+    {
+        return $this->imports;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitImportRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@import ' . implode(', ', $this->imports) . ';';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/IncludeRule.php

@@ -0,0 +1,149 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\CallableInvocation;
+use ScssPhp\ScssPhp\Ast\Sass\SassReference;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A mixin invocation.
+ *
+ * @internal
+ */
+final class IncludeRule implements Statement, CallableInvocation, SassReference
+{
+    /**
+     * @var string|null
+     * @readonly
+     */
+    private $namespace;
+
+    /**
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var ArgumentInvocation
+     * @readonly
+     */
+    private $arguments;
+
+    /**
+     * @var ContentBlock|null
+     * @readonly
+     */
+    private $content;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $name, ArgumentInvocation $arguments, FileSpan $span, ?string $namespace = null,?ContentBlock $content = null)
+    {
+        $this->name = $name;
+        $this->arguments = $arguments;
+        $this->span = $span;
+        $this->namespace = $namespace;
+        $this->content = $content;
+    }
+
+    public function getNamespace(): ?string
+    {
+        return $this->namespace;
+    }
+
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    public function getArguments(): ArgumentInvocation
+    {
+        return $this->arguments;
+    }
+
+    public function getContent(): ?ContentBlock
+    {
+        return $this->content;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function getSpanWithoutContent(): FileSpan
+    {
+        if ($this->content === null) {
+            return $this->span;
+        }
+
+        return SpanUtil::trim($this->span->getFile()->span($this->span->getStart()->getOffset(), $this->arguments->getSpan()->getEnd()->getOffset()));
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        $startSpan = $this->span->getText()[0] === '+' ? SpanUtil::trimLeft($this->span->subspan(1)) : SpanUtil::withoutInitialAtRule($this->span);
+
+        if ($this->namespace !== null) {
+            $startSpan = SpanUtil::withoutNamespace($startSpan);
+        }
+
+        return SpanUtil::initialIdentifier($startSpan);
+    }
+
+    public function getNamespaceSpan(): ?FileSpan
+    {
+        if ($this->namespace === null) {
+            return null;
+        }
+
+        $startSpan = $this->span->getText()[0] === '+'
+            ? SpanUtil::trimLeft($this->span->subspan(1))
+            : SpanUtil::withoutInitialAtRule($this->span);
+
+        return SpanUtil::initialIdentifier($startSpan);
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitIncludeRule($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '@include ';
+
+        if ($this->namespace !== null) {
+            $buffer .= $this->namespace . '.';
+        }
+        $buffer .= $this->name;
+
+        if (!$this->arguments->isEmpty()) {
+            $buffer .= "($this->arguments)";
+        }
+
+        $buffer .= $this->content === null ? ';' : ' ' . $this->content;
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/LoudComment.php

@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A loud CSS-style comment.
+ *
+ * @internal
+ */
+final class LoudComment implements Statement
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $text;
+
+    public function __construct(Interpolation $text)
+    {
+        $this->text = $text;
+    }
+
+    public function getText(): Interpolation
+    {
+        return $this->text;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->text->getSpan();
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitLoudComment($this);
+    }
+
+    public function __toString(): string
+    {
+        return (string) $this->text;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/MediaRule.php

@@ -0,0 +1,75 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@media` rule.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class MediaRule extends ParentStatement
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $query;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(Interpolation $query, array $children, FileSpan $span)
+    {
+        $this->query = $query;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    /**
+     * The query that determines on which platforms the styles will be in effect.
+     *
+     * This is only parsed after the interpolation has been resolved.
+     */
+    public function getQuery(): Interpolation
+    {
+        return $this->query;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitMediaRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@media ' . $this->query . ' {' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/MixinRule.php

@@ -0,0 +1,81 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\ArgumentDeclaration;
+use ScssPhp\ScssPhp\Ast\Sass\SassDeclaration;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A mixin declaration.
+ *
+ * This declares a mixin that's invoked using `@include`.
+ *
+ * @internal
+ */
+final class MixinRule extends CallableDeclaration implements SassDeclaration
+{
+    /**
+     * Whether the mixin contains a `@content` rule.
+     *
+     * @var bool|null
+     */
+    private $content;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(string $name, ArgumentDeclaration $arguments, FileSpan $span, array $children, ?SilentComment $comment = null)
+    {
+        parent::__construct($name, $arguments, $span, $children, $comment);
+    }
+
+    public function hasContent(): bool
+    {
+        if (!isset($this->content)) {
+            $this->content = (new HasContentVisitor())->visitMixinRule($this) === true;
+        }
+
+        return $this->content;
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        $startSpan = $this->getSpan()->getText()[0] === '='
+            ? SpanUtil::trimLeft($this->getSpan()->subspan(1))
+            : SpanUtil::withoutInitialAtRule($this->getSpan());
+
+        return SpanUtil::initialIdentifier($startSpan);
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitMixinRule($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '@mixin ' . $this->getName();
+
+        if (!$this->getArguments()->isEmpty()) {
+            $buffer .= "({$this->getArguments()})";
+        }
+
+        $buffer .= ' {' . implode(' ', $this->getChildren()) . '}';
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ParentStatement.php

@@ -0,0 +1,86 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Import\DynamicImport;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+/**
+ * A {@see Statement} that can have child statements.
+ *
+ * This has a generic parameter so that its subclasses can choose whether or
+ * not their children lists are nullable.
+ *
+ * @template T
+ * @psalm-template T of (Statement[]|null)
+ *
+ * @internal
+ */
+abstract class ParentStatement implements Statement
+{
+    /**
+     * @var T
+     * @readonly
+     */
+    private $children;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $declarations;
+
+    /**
+     * @param T $children
+     */
+    public function __construct(?array $children)
+    {
+        $this->children = $children;
+
+        if ($children === null) {
+            $this->declarations = false;
+            return;
+        }
+
+        foreach ($children as $child) {
+            if ($child instanceof VariableDeclaration || $child instanceof FunctionRule || $child instanceof MixinRule) {
+                $this->declarations = true;
+                return;
+            }
+
+            if ($child instanceof ImportRule) {
+                foreach ($child->getImports() as $import) {
+                    if ($import instanceof DynamicImport) {
+                        $this->declarations = true;
+                        return;
+                    }
+                }
+            }
+        }
+
+        $this->declarations = false;
+    }
+
+    /**
+     * @return T
+     */
+    final public function getChildren()
+    {
+        return $this->children;
+    }
+
+    final public function hasDeclarations(): bool
+    {
+        return $this->declarations;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/ReturnRule.php

@@ -0,0 +1,66 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@return` rule.
+ *
+ * This exits from the current function body with a return value.
+ *
+ * @internal
+ */
+final class ReturnRule implements Statement
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Expression $expression, FileSpan $span)
+    {
+        $this->expression = $expression;
+        $this->span = $span;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitReturnRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@return ' . $this->expression . ';';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/SilentComment.php

@@ -0,0 +1,63 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A silent Sass-style comment.
+ *
+ * @internal
+ */
+final class SilentComment implements Statement
+{
+    /**
+     * @var string
+     * @readonly
+     */
+    private $text;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $text, FileSpan $span)
+    {
+        $this->text = $text;
+        $this->span = $span;
+    }
+
+    public function getText(): string
+    {
+        return $this->text;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitSilentComment($this);
+    }
+
+    public function __toString(): string
+    {
+        return $this->text;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/StyleRule.php

@@ -0,0 +1,77 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Interpolation;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A style rule.
+ *
+ * This applies style declarations to elements that match a given selector.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class StyleRule extends ParentStatement
+{
+    /**
+     * @var Interpolation
+     * @readonly
+     */
+    private $selector;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(Interpolation $selector, array $children, FileSpan $span)
+    {
+        $this->selector = $selector;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    /**
+     * The selector to which the declaration will be applied.
+     *
+     * This is only parsed after the interpolation has been resolved.
+     */
+    public function getSelector(): Interpolation
+    {
+        return $this->selector;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitStyleRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return $this->selector . ' {' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/Stylesheet.php

@@ -0,0 +1,126 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\Exception\SassFormatException;
+use ScssPhp\ScssPhp\Logger\LoggerInterface;
+use ScssPhp\ScssPhp\Parser\CssParser;
+use ScssPhp\ScssPhp\Parser\ScssParser;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\SourceSpan\SourceFile;
+use ScssPhp\ScssPhp\Syntax;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A Sass stylesheet.
+ *
+ * This is the root Sass node. It contains top-level statements.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class Stylesheet extends ParentStatement
+{
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $plainCss;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(array $children, FileSpan $span, bool $plainCss = false)
+    {
+        $this->span = $span;
+        $this->plainCss = $plainCss;
+        parent::__construct($children);
+    }
+
+    public function isPlainCss(): bool
+    {
+        return $this->plainCss;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitStylesheet($this);
+    }
+
+    /**
+     * @param Syntax::* $syntax
+     *
+     * @throws SassFormatException when parsing fails
+     */
+    public static function parse(string $contents, string $syntax, ?LoggerInterface $logger = null, ?string $sourceUrl = null): self
+    {
+        switch ($syntax) {
+            case Syntax::SASS:
+                return self::parseSass($contents, $logger, $sourceUrl);
+
+            case Syntax::SCSS:
+                return self::parseScss($contents, $logger, $sourceUrl);
+
+            case Syntax::CSS:
+                return self::parseCss($contents, $logger, $sourceUrl);
+
+            default:
+                throw new \InvalidArgumentException("Unknown syntax $syntax.");
+        }
+    }
+
+    /**
+     * @throws SassFormatException when parsing fails
+     */
+    public static function parseSass(string $contents, ?LoggerInterface $logger = null, ?string $sourceUrl = null): self
+    {
+        $file = new SourceFile($contents, $sourceUrl);
+        $span = $file->span(0, 0);
+
+        throw new SassFormatException('The Sass indented syntax is not implemented.', $span);
+    }
+
+    /**
+     * @throws SassFormatException when parsing fails
+     */
+    public static function parseScss(string $contents, ?LoggerInterface $logger = null, ?string $sourceUrl = null): self
+    {
+        return (new ScssParser($contents, $logger, $sourceUrl))->parse();
+    }
+
+    /**
+     * @throws SassFormatException when parsing fails
+     */
+    public static function parseCss(string $contents, ?LoggerInterface $logger = null, ?string $sourceUrl = null): self
+    {
+        return (new CssParser($contents, $logger, $sourceUrl))->parse();
+    }
+
+    public function __toString(): string
+    {
+        return implode(' ', $this->getChildren());
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/SupportsRule.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\Ast\Sass\SupportsCondition;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@supports` rule.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class SupportsRule extends ParentStatement
+{
+    /**
+     * @var SupportsCondition
+     * @readonly
+     */
+    private $condition;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(SupportsCondition $condition, array $children, FileSpan $span)
+    {
+        $this->condition = $condition;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    public function getCondition(): SupportsCondition
+    {
+        return $this->condition;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitSupportsRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@supports ' . $this->condition . ' {' . implode(' ', $this->getChildren()) . '}';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/VariableDeclaration.php

@@ -0,0 +1,174 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\SassDeclaration;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Util;
+use ScssPhp\ScssPhp\Util\SpanUtil;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A variable declaration.
+ *
+ * This defines or sets a variable.
+ *
+ * @internal
+ */
+final class VariableDeclaration implements Statement, SassDeclaration
+{
+    /**
+     * @var string|null
+     * @readonly
+     */
+    private $namespace;
+
+    /**
+     * @var string
+     * @readonly
+     */
+    private $name;
+
+    /**
+     * @var SilentComment|null
+     * @readonly
+     */
+    private $comment;
+
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $guarded;
+
+    /**
+     * @var bool
+     * @readonly
+     */
+    private $global;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(string $name, Expression $expression, FileSpan $span, ?string $namespace = null, bool $guarded = false, bool $global = false, ?SilentComment $comment = null)
+    {
+        $this->name = $name;
+        $this->expression = $expression;
+        $this->span = $span;
+        $this->namespace = $namespace;
+        $this->guarded = $guarded;
+        $this->global = $global;
+        $this->comment = $comment;
+
+        if ($namespace !== null && $global) {
+            throw new \InvalidArgumentException("Other modules' members can't be defined with !global.");
+        }
+    }
+
+    public function getNamespace(): ?string
+    {
+        return $this->namespace;
+    }
+
+    /**
+     * The name of the variable, with underscores converted to hyphens.
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * The variable name as written in the document, without underscores
+     * converted to hyphens and including the leading `$`.
+     *
+     * This isn't particularly efficient, and should only be used for error
+     * messages.
+     */
+    public function getOriginalName(): string
+    {
+        return Util::declarationName($this->span);
+    }
+
+    public function getComment(): ?SilentComment
+    {
+        return $this->comment;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function isGuarded(): bool
+    {
+        return $this->guarded;
+    }
+
+    public function isGlobal(): bool
+    {
+        return $this->global;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function getNameSpan(): FileSpan
+    {
+        $span = $this->span;
+
+        if ($this->namespace !== null) {
+            $span = SpanUtil::withoutNamespace($span);
+        }
+
+        return SpanUtil::initialIdentifier($span, 1);
+    }
+
+    public function getNamespaceSpan(): ?FileSpan
+    {
+        if ($this->namespace === null) {
+            return null;
+        }
+
+        return SpanUtil::initialIdentifier($this->span);
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitVariableDeclaration($this);
+    }
+
+    public function __toString(): string
+    {
+        $buffer = '';
+        if ($this->namespace !== null) {
+            $buffer .= $this->namespace . '.';
+        }
+        $buffer .= "\$$this->name: $this->expression;";
+
+        return $buffer;
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/WarnRule.php

@@ -0,0 +1,66 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@warn` rule.
+ *
+ * This prints a Sass value—usually a string—to warn the user of something.
+ *
+ * @internal
+ */
+final class WarnRule implements Statement
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $expression;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    public function __construct(Expression $expression, FileSpan $span)
+    {
+        $this->expression = $expression;
+        $this->span = $span;
+    }
+
+    public function getExpression(): Expression
+    {
+        return $this->expression;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitWarnRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@warn ' . $this->expression . ';';
+    }
+}

wp-content/plugins/wp-scss/scssphp/src/Ast/Sass/Statement/WhileRule.php

@@ -0,0 +1,73 @@
+<?php
+
+/**
+ * SCSSPHP
+ *
+ * @copyright 2012-2020 Leaf Corcoran
+ *
+ * @license http://opensource.org/licenses/MIT MIT
+ *
+ * @link http://scssphp.github.io/scssphp
+ */
+
+namespace ScssPhp\ScssPhp\Ast\Sass\Statement;
+
+use ScssPhp\ScssPhp\Ast\Sass\Expression;
+use ScssPhp\ScssPhp\Ast\Sass\Statement;
+use ScssPhp\ScssPhp\SourceSpan\FileSpan;
+use ScssPhp\ScssPhp\Visitor\StatementVisitor;
+
+/**
+ * A `@while` rule.
+ *
+ * This repeatedly executes a block of code as long as a statement evaluates to
+ * `true`.
+ *
+ * @extends ParentStatement<Statement[]>
+ *
+ * @internal
+ */
+final class WhileRule extends ParentStatement
+{
+    /**
+     * @var Expression
+     * @readonly
+     */
+    private $condition;
+
+    /**
+     * @var FileSpan
+     * @readonly
+     */
+    private $span;
+
+    /**
+     * @param Statement[] $children
+     */
+    public function __construct(Expression $condition, array $children, FileSpan $span)
+    {
+        $this->condition = $condition;
+        $this->span = $span;
+        parent::__construct($children);
+    }
+
+    public function getCondition(): Expression
+    {
+        return $this->condition;
+    }
+
+    public function getSpan(): FileSpan
+    {
+        return $this->span;
+    }
+
+    public function accept(StatementVisitor $visitor)
+    {
+        return $visitor->visitWhileRule($this);
+    }
+
+    public function __toString(): string
+    {
+        return '@while ' . $this->condition . ' {' . implode(' ', $this->getChildren()) . '}';
+    }
+}