Add Tailwind CSS Standalone CLI utility filter

.github/workflows/tests.yml

@@ -24,6 +24,13 @@ jobs:
           sudo apt-get -y install jpegoptim libjpeg-progs optipng
           npm install
 
+      - name: Install Tailwind CSS Standalone CLI
+        uses: supplypike/setup-bin@v4
+        with:
+            uri: 'https://github.com/tailwindlabs/tailwindcss/releases/download/v3.4.4/tailwindcss-linux-x64'
+            name: 'tailwindcss'
+            version: '3.4.4'
+
       - name: Install PHP
         uses: shivammathur/setup-php@v2
         with:

src/Assetic/Filter/BaseProcessFilter.php

@@ -16,6 +16,11 @@ abstract class BaseProcessFilter extends BaseFilter
      */
     protected $binaryPath;
 
+    /**
+     * @var string|null Defines the working directory for the process.
+     */
+    protected $workingDirectory = null;
+
     /**
      * @var boolean Flag to indicate that the process will output the result to the input file
      */
@@ -75,6 +80,25 @@ public function setTimeout($timeout)
         $this->timeout = $timeout;
     }
 
+    /**
+     * Sets the binary path for the process.
+     */
+    public function setBinaryPath(string $binaryPath): void
+    {
+        $this->binaryPath = $binaryPath;
+    }
+
+    /**
+     * Sets the working directory for the process.
+     *
+     * Some processes may require a specified working directory to function correctly, ie. locating configurations,
+     * assets, etc.
+     */
+    public function setWorkingDirectory(?string $workingDirectory = null): void
+    {
+        $this->workingDirectory = $workingDirectory;
+    }
+
     /**
      * Creates a new process.
      *
@@ -83,7 +107,7 @@ public function setTimeout($timeout)
      */
     protected function createProcess(array $arguments = [])
     {
-        $process = new Process($arguments);
+        $process = new Process($arguments, $this->workingDirectory);
 
         if (null !== $this->timeout) {
             $process->setTimeout($this->timeout);

src/Assetic/Filter/TailwindCssFilter.php

@@ -0,0 +1,88 @@
+<?php
+
+namespace Assetic\Filter;
+
+use Assetic\Contracts\Asset\AssetInterface;
+
+/**
+ * Tailwind CSS filter.
+ *
+ * Compiles Tailwind CSS into standard CSS, using the standalone Tailwind CSS CLI tool.
+ *
+ * @author Ben Thomson <[email protected]>
+ */
+class TailwindCssFilter extends BaseProcessFilter
+{
+    /**
+     * @var string Path to the binary for this process based filter
+     */
+    protected $binaryPath = '/usr/bin/tailwindcss';
+
+    /**
+     * @var string|null Path to the Tailwind configuration file.
+     */
+    protected $configPath = null;
+
+    /**
+     * @var bool Is minification enabled?
+     */
+    protected $minify = false;
+
+    /**
+     * @var bool Is autoprefixing enabled?
+     */
+    protected $autoprefix = true;
+
+    /**
+     * Sets the path for the configuration file.
+     */
+    public function setConfigPath(string $configPath): void
+    {
+        $this->configPath = $configPath;
+    }
+
+    /**
+     * Enable minification.
+     */
+    public function minify(): void
+    {
+        $this->minify = true;
+    }
+
+    /**
+     * Disable autoprefixer.
+     */
+    public function withoutAutoprefixing(): void
+    {
+        $this->autoprefix = false;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function filterLoad(AssetInterface $asset)
+    {
+        $args = [
+            '--input',
+            '{INPUT}',
+            '--output',
+            '{OUTPUT}'
+        ];
+
+        if (!is_null($this->configPath)) {
+            $args[] = '--config';
+            $args[] = $this->configPath;
+        }
+
+        if ($this->minify) {
+            $args[] = '--minify';
+        }
+
+        if (!$this->autoprefix) {
+            $args[] = '--no-autoprefixer';
+        }
+
+        $result = $this->runProcess($asset->getContent(), $args);
+        $asset->setContent($result);
+    }
+}

tests/Assetic/Test/Filter/TailwindCssFilterTest.php

@@ -0,0 +1,89 @@
+<?php
+
+namespace Assetic\Test\Filter;
+
+use Assetic\Asset\FileAsset;
+use Assetic\Filter\TailwindCssFilter;
+
+/**
+ * @group integration
+ */
+class TailwindCssFilterTest extends FilterTestCase
+{
+    /** @var TailwindCssFilter|null */
+    private $filter;
+
+    protected function setUp(): void
+    {
+        $tailwindCssBin = $this->findExecutable('tailwindcss', 'TAILWINDCSS_BIN');
+
+        if (!$tailwindCssBin) {
+            $this->markTestSkipped('Unable to find `tailwindcss` executable.');
+        }
+
+        $this->filter = new TailwindCssFilter($tailwindCssBin);
+    }
+
+    protected function tearDown(): void
+    {
+        $this->filter = null;
+    }
+
+    public function testFilterLoad()
+    {
+        $fileAsset = new FileAsset(__DIR__ . '/fixtures/tailwindcss/css/style.css');
+        $fileAsset->load();
+
+        $this->filter->setConfigPath(__DIR__ . '/fixtures/tailwindcss/tailwind.config.js');
+        $this->filter->setWorkingDirectory(__DIR__ . '/fixtures/tailwindcss');
+        $this->filter->filterLoad($fileAsset);
+        $contents = $fileAsset->getContent();
+
+        // Detect boilerplate TailwindCSS styling
+        $expected = <<<'STYLE'
+            ::backdrop {
+              --tw-border-spacing-x: 0;
+              --tw-border-spacing-y: 0;
+              --tw-translate-x: 0;
+              --tw-translate-y: 0;
+            STYLE;
+
+        $this->assertStringContainsString($expected, $contents);
+
+        // Detect class defined in HTML
+        $expected = <<<'STYLE'
+            .text-gray-800 {
+              --tw-text-opacity: 1;
+              color: rgb(31 41 55 / var(--tw-text-opacity));
+            }
+            STYLE;
+
+        $this->assertStringContainsString($expected, $contents);
+    }
+
+    public function testFilterLoadWithMinification()
+    {
+        $fileAsset = new FileAsset(__DIR__ . '/fixtures/tailwindcss/css/style.css');
+        $fileAsset->load();
+
+        $this->filter->setConfigPath(__DIR__ . '/fixtures/tailwindcss/tailwind.config.js');
+        $this->filter->setWorkingDirectory(__DIR__ . '/fixtures/tailwindcss');
+        $this->filter->minify();
+        $this->filter->filterLoad($fileAsset);
+        $contents = $fileAsset->getContent();
+
+        // Detect boilerplate TailwindCSS styling
+        $expected = <<<'STYLE'
+            *,::backdrop,:after,:before{--tw-border-spacing-x:0;--tw-border-spacing-y:0;--tw-translate-x:0;--tw-translate-y:0;
+            STYLE;
+
+        $this->assertStringContainsString($expected, $contents);
+
+        // Detect class defined in HTML
+        $expected = <<<'STYLE'
+            .text-gray-800{--tw-text-opacity:1;color:rgb(31 41 55/var(--tw-text-opacity))}
+            STYLE;
+
+        $this->assertStringContainsString($expected, $contents);
+    }
+}

tests/Assetic/Test/Filter/fixtures/tailwindcss/css/style.css

@@ -0,0 +1,3 @@
+@tailwind base;
+@tailwind components;
+@tailwind utilities;

tests/Assetic/Test/Filter/fixtures/tailwindcss/html/index.html

@@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Tailwind CSS test</title>
+</head>
+<body class="antialiased bg-white text-gray-800">
+    <div class="flex flex-row gap-10">
+        <div class="bg-red text-white p-4">Red</div>
+        <div class="bg-green text-white p-4">Green</div>
+        <div class="bg-blue text-white p-4">Blue</div>
+    </div>
+</body>
+</html>

tests/Assetic/Test/Filter/fixtures/tailwindcss/tailwind.config.js

@@ -0,0 +1,8 @@
+/** @type {import('tailwindcss').Config} */
+module.exports = {
+    content: ["./html/**/*.html"],
+    theme: {
+      extend: {},
+    },
+    plugins: [],
+  }