From 017f9351a738d980c175fb82c12521b38537f969 Mon Sep 17 00:00:00 2001
From: DorZuberi <admin@dorzki.io>
Date: Sun, 29 Mar 2026 18:10:34 +0300
Subject: [PATCH] Add SCSS language support with patterns and tests

---
 src/Highlighter.php                           |   2 +
 .../Scss/Patterns/ScssCommentPattern.php      |  27 +++++
 .../Patterns/ScssInterpolationPattern.php     |  27 +++++
 .../Scss/Patterns/ScssKeywordPattern.php      |  33 ++++++
 .../Scss/Patterns/ScssSelectorPattern.php     |  28 +++++
 .../Scss/Patterns/ScssVariablePattern.php     |  28 +++++
 src/Languages/Scss/ScssLanguage.php           |  42 ++++++++
 tests/Bench/Fixtures/scss.txt                 | 100 ++++++++++++++++++
 tests/Bench/HighlighterBench.php              |   1 +
 tests/Languages/Scss/ScssLanguageTest.php     |  79 ++++++++++++++
 10 files changed, 367 insertions(+)
 create mode 100644 src/Languages/Scss/Patterns/ScssCommentPattern.php
 create mode 100644 src/Languages/Scss/Patterns/ScssInterpolationPattern.php
 create mode 100644 src/Languages/Scss/Patterns/ScssKeywordPattern.php
 create mode 100644 src/Languages/Scss/Patterns/ScssSelectorPattern.php
 create mode 100644 src/Languages/Scss/Patterns/ScssVariablePattern.php
 create mode 100644 src/Languages/Scss/ScssLanguage.php
 create mode 100644 tests/Bench/Fixtures/scss.txt
 create mode 100644 tests/Languages/Scss/ScssLanguageTest.php

diff --git a/src/Highlighter.php b/src/Highlighter.php
index 1374bd4..19c8413 100644
--- a/src/Highlighter.php
+++ b/src/Highlighter.php
@@ -21,6 +21,7 @@
 use Tempest\Highlight\Languages\Markdown\MarkdownLanguage;
 use Tempest\Highlight\Languages\Php\PhpLanguage;
 use Tempest\Highlight\Languages\Python\PythonLanguage;
+use Tempest\Highlight\Languages\Scss\ScssLanguage;
 use Tempest\Highlight\Languages\Sql\SqlLanguage;
 use Tempest\Highlight\Languages\Text\TextLanguage;
 use Tempest\Highlight\Languages\Twig\TwigLanguage;
@@ -64,6 +65,7 @@ public function __construct(private readonly Theme $theme = new CssTheme())
             ->addLanguage(new MarkdownLanguage())
             ->addLanguage(new PhpLanguage())
             ->addLanguage(new PythonLanguage())
+            ->addLanguage(new ScssLanguage())
             ->addLanguage(new SqlLanguage())
             ->addLanguage(new XmlLanguage())
             ->addLanguage(new YamlLanguage())
diff --git a/src/Languages/Scss/Patterns/ScssCommentPattern.php b/src/Languages/Scss/Patterns/ScssCommentPattern.php
new file mode 100644
index 0000000..7bcaf6d
--- /dev/null
+++ b/src/Languages/Scss/Patterns/ScssCommentPattern.php
@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Languages\Scss\Patterns;
+
+use Tempest\Highlight\IsPattern;
+use Tempest\Highlight\Pattern;
+use Tempest\Highlight\PatternTest;
+use Tempest\Highlight\Tokens\TokenTypeEnum;
+
+#[PatternTest(input: '// this is a comment', output: '// this is a comment')]
+#[PatternTest(input: 'color: red; // inline comment', output: '// inline comment')]
+final readonly class ScssCommentPattern implements Pattern
+{
+    use IsPattern;
+
+    public function getPattern(): string
+    {
+        return '/(?<match>\/\/.*)/';
+    }
+
+    public function getTokenType(): TokenTypeEnum
+    {
+        return TokenTypeEnum::COMMENT;
+    }
+}
diff --git a/src/Languages/Scss/Patterns/ScssInterpolationPattern.php b/src/Languages/Scss/Patterns/ScssInterpolationPattern.php
new file mode 100644
index 0000000..bebcdfc
--- /dev/null
+++ b/src/Languages/Scss/Patterns/ScssInterpolationPattern.php
@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Languages\Scss\Patterns;
+
+use Tempest\Highlight\IsPattern;
+use Tempest\Highlight\Pattern;
+use Tempest\Highlight\PatternTest;
+use Tempest\Highlight\Tokens\TokenTypeEnum;
+
+#[PatternTest(input: 'content: "#{$name}";', output: '#{$name}')]
+#[PatternTest(input: '.#{$class}-item {', output: '#{$class}')]
+final readonly class ScssInterpolationPattern implements Pattern
+{
+    use IsPattern;
+
+    public function getPattern(): string
+    {
+        return '(?<match>#\{\$[\w\-]+\})';
+    }
+
+    public function getTokenType(): TokenTypeEnum
+    {
+        return TokenTypeEnum::VARIABLE;
+    }
+}
diff --git a/src/Languages/Scss/Patterns/ScssKeywordPattern.php b/src/Languages/Scss/Patterns/ScssKeywordPattern.php
new file mode 100644
index 0000000..23a07ff
--- /dev/null
+++ b/src/Languages/Scss/Patterns/ScssKeywordPattern.php
@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Languages\Scss\Patterns;
+
+use Tempest\Highlight\IsPattern;
+use Tempest\Highlight\Pattern;
+use Tempest\Highlight\PatternTest;
+use Tempest\Highlight\Tokens\TokenTypeEnum;
+
+#[PatternTest(input: '@mixin rounded {', output: '@mixin')]
+#[PatternTest(input: '@include rounded;', output: '@include')]
+#[PatternTest(input: '@extend .base;', output: '@extend')]
+#[PatternTest(input: '@if $dark {', output: '@if')]
+#[PatternTest(input: '@each $color in $colors {', output: '@each')]
+#[PatternTest(input: "@use 'colors';", output: '@use')]
+#[PatternTest(input: '@function double($value) {', output: '@function')]
+#[PatternTest(input: '@return $value * 2;', output: '@return')]
+final readonly class ScssKeywordPattern implements Pattern
+{
+    use IsPattern;
+
+    public function getPattern(): string
+    {
+        return '(?<match>@(?:mixin|include|extend|function|return|if|else|for|each|while|use|forward|at-root|debug|warn|error))\b';
+    }
+
+    public function getTokenType(): TokenTypeEnum
+    {
+        return TokenTypeEnum::KEYWORD;
+    }
+}
diff --git a/src/Languages/Scss/Patterns/ScssSelectorPattern.php b/src/Languages/Scss/Patterns/ScssSelectorPattern.php
new file mode 100644
index 0000000..42b0976
--- /dev/null
+++ b/src/Languages/Scss/Patterns/ScssSelectorPattern.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Languages\Scss\Patterns;
+
+use Tempest\Highlight\IsPattern;
+use Tempest\Highlight\Pattern;
+use Tempest\Highlight\PatternTest;
+use Tempest\Highlight\Tokens\TokenTypeEnum;
+
+#[PatternTest(input: '&:hover {', output: '&:hover ')]
+#[PatternTest(input: '%placeholder {', output: '%placeholder ')]
+#[PatternTest(input: '& .child {', output: '& .child ')]
+final readonly class ScssSelectorPattern implements Pattern
+{
+    use IsPattern;
+
+    public function getPattern(): string
+    {
+        return '(?<match>[\[\]\'\"\=\@\-\#\.\w\s,\n\+\:\(\)\*\&\%]+)\{';
+    }
+
+    public function getTokenType(): TokenTypeEnum
+    {
+        return TokenTypeEnum::KEYWORD;
+    }
+}
diff --git a/src/Languages/Scss/Patterns/ScssVariablePattern.php b/src/Languages/Scss/Patterns/ScssVariablePattern.php
new file mode 100644
index 0000000..cd5105c
--- /dev/null
+++ b/src/Languages/Scss/Patterns/ScssVariablePattern.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Languages\Scss\Patterns;
+
+use Tempest\Highlight\IsPattern;
+use Tempest\Highlight\Pattern;
+use Tempest\Highlight\PatternTest;
+use Tempest\Highlight\Tokens\TokenTypeEnum;
+
+#[PatternTest(input: '$primary-color: #333;', output: '$primary-color')]
+#[PatternTest(input: 'color: $primary-color;', output: '$primary-color')]
+#[PatternTest(input: 'border: 1px solid $border-color;', output: '$border-color')]
+final readonly class ScssVariablePattern implements Pattern
+{
+    use IsPattern;
+
+    public function getPattern(): string
+    {
+        return '(?<match>\$[\w\-]+)';
+    }
+
+    public function getTokenType(): TokenTypeEnum
+    {
+        return TokenTypeEnum::VARIABLE;
+    }
+}
diff --git a/src/Languages/Scss/ScssLanguage.php b/src/Languages/Scss/ScssLanguage.php
new file mode 100644
index 0000000..19acf39
--- /dev/null
+++ b/src/Languages/Scss/ScssLanguage.php
@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Languages\Scss;
+
+use Override;
+use Tempest\Highlight\Languages\Css\CssLanguage;
+use Tempest\Highlight\Languages\Scss\Patterns\ScssCommentPattern;
+use Tempest\Highlight\Languages\Scss\Patterns\ScssInterpolationPattern;
+use Tempest\Highlight\Languages\Scss\Patterns\ScssKeywordPattern;
+use Tempest\Highlight\Languages\Scss\Patterns\ScssSelectorPattern;
+use Tempest\Highlight\Languages\Scss\Patterns\ScssVariablePattern;
+
+class ScssLanguage extends CssLanguage
+{
+    public function getName(): string
+    {
+        return 'scss';
+    }
+
+    #[Override]
+    public function getInjections(): array
+    {
+        return [
+            ...parent::getInjections(),
+        ];
+    }
+
+    #[Override]
+    public function getPatterns(): array
+    {
+        return [
+            ...parent::getPatterns(),
+            new ScssSelectorPattern(),
+            new ScssCommentPattern(),
+            new ScssVariablePattern(),
+            new ScssKeywordPattern(),
+            new ScssInterpolationPattern(),
+        ];
+    }
+}
diff --git a/tests/Bench/Fixtures/scss.txt b/tests/Bench/Fixtures/scss.txt
new file mode 100644
index 0000000..4066300
--- /dev/null
+++ b/tests/Bench/Fixtures/scss.txt
@@ -0,0 +1,100 @@
+$primary-color: #3b82f6;
+$secondary-color: #6366f1;
+$spacing-unit: 0.25rem;
+$font-sans: 'Inter', system-ui, -apple-system, sans-serif;
+$breakpoint-md: 768px;
+
+@mixin flex-center {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+}
+
+@mixin responsive($breakpoint) {
+    @media (max-width: $breakpoint) {
+        @content;
+    }
+}
+
+@function spacing($multiplier) {
+    @return $spacing-unit * $multiplier;
+}
+
+%card-base {
+    background: white;
+    border-radius: 0.75rem;
+    padding: spacing(6);
+}
+
+body {
+    font-family: $font-sans;
+    line-height: 1.6;
+    color: #1f2937;
+    background-color: #f9fafb;
+}
+
+.container {
+    max-width: 1200px;
+    margin: 0 auto;
+    padding: 0 spacing(4);
+}
+
+.card {
+    @extend %card-base;
+    box-shadow: 0 10px 15px -3px rgb(0 0 0 / 0.1);
+    transition: transform 0.2s ease-in-out;
+
+    &:hover {
+        transform: translateY(-2px);
+    }
+
+    &__title {
+        font-size: 1.25rem;
+        color: $primary-color;
+    }
+
+    &__body {
+        padding: spacing(4);
+    }
+}
+
+.btn {
+    @include flex-center;
+    padding: spacing(2) spacing(4);
+    border-radius: 0.375rem;
+    cursor: pointer;
+
+    &-primary {
+        background-color: $primary-color;
+        color: white;
+
+        &:hover {
+            background-color: darken($primary-color, 10%);
+        }
+    }
+}
+
+// Responsive utilities
+@each $size in sm, md, lg {
+    .hide-#{$size} {
+        @include responsive($breakpoint-md) {
+            display: none;
+        }
+    }
+}
+
+@if $primary-color == #3b82f6 {
+    .themed {
+        color: $primary-color;
+    }
+} @else {
+    .themed {
+        color: $secondary-color;
+    }
+}
+
+/* Multi-line comment
+   still works in SCSS */
+.fade-in {
+    animation: fadeIn 0.3s ease-out forwards;
+}
\ No newline at end of file
diff --git a/tests/Bench/HighlighterBench.php b/tests/Bench/HighlighterBench.php
index 0516f96..b751fed 100644
--- a/tests/Bench/HighlighterBench.php
+++ b/tests/Bench/HighlighterBench.php
@@ -31,6 +31,7 @@ final class HighlighterBench
         'markdown' => 'markdown.txt',
         'php' => 'php.txt',
         'python' => 'python.txt',
+        'scss' => 'scss.txt',
         'sql' => 'sql.txt',
         'twig' => 'twig.txt',
         'xml' => 'xml.txt',
diff --git a/tests/Languages/Scss/ScssLanguageTest.php b/tests/Languages/Scss/ScssLanguageTest.php
new file mode 100644
index 0000000..9de3735
--- /dev/null
+++ b/tests/Languages/Scss/ScssLanguageTest.php
@@ -0,0 +1,79 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tempest\Highlight\Tests\Languages\Scss;
+
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\TestCase;
+use Tempest\Highlight\Highlighter;
+
+class ScssLanguageTest extends TestCase
+{
+    #[DataProvider('provide_highlight_cases')]
+    public function test_highlight(string $content, string $expected): void
+    {
+        $highlighter = new Highlighter();
+
+        $this->assertSame(
+            $expected,
+            $highlighter->parse($content, 'scss'),
+        );
+    }
+
+    public static function provide_highlight_cases(): iterable
+    {
+        return [
+            // SCSS variable
+            [
+                '$primary: #333;',
+                '<span class="hl-variable">$primary</span>: #333;',
+            ],
+            // Single-line comment
+            [
+                '// this is a comment',
+                '<span class="hl-comment">// this is a comment</span>',
+            ],
+            // Mixin definition
+            [
+                '@mixin rounded {',
+                '<span class="hl-keyword">@mixin rounded </span>{',
+            ],
+            // @include
+            [
+                '@include rounded;',
+                '<span class="hl-keyword">@include</span> rounded;',
+            ],
+            // Parent selector (& is HTML-encoded)
+            [
+                '&:hover {',
+                '<span class="hl-keyword">&amp;:hover </span>{',
+            ],
+            // Placeholder selector
+            [
+                '%placeholder {',
+                '<span class="hl-keyword">%placeholder </span>{',
+            ],
+            // @each keyword with variables
+            [
+                '@each $color in $colors {',
+                '<span class="hl-keyword">@each</span> <span class="hl-variable">$color</span> in <span class="hl-variable">$colors</span> {',
+            ],
+            // CSS features still work
+            [
+                '@media only screen and (max-width: 500px) {}',
+                '<span class="hl-keyword">@media only screen and (max-width: 500px) </span>{}',
+            ],
+            // CSS property
+            [
+                'color: $primary;',
+                '<span class="hl-property">color</span>: <span class="hl-variable">$primary</span>;',
+            ],
+            // SCSS function
+            [
+                'background: darken($color, 10%);',
+                '<span class="hl-property">background</span>: <span class="hl-keyword">darken</span>(<span class="hl-variable">$color</span>, 10%);',
+            ],
+        ];
+    }
+}