Add support for dart imports

src/Assetic/Filter/DartFilter.php

@@ -13,27 +13,63 @@
 
 use Assetic\Asset\AssetInterface;
 use Assetic\Exception\FilterException;
+use Assetic\Factory\AssetFactory;
+use Assetic\Util\DartUtils;
 
 /**
  * Compiles Dart into Javascript.
  *
  * @link http://dartlang.org/
  */
-class DartFilter extends BaseProcessFilter
+class DartFilter extends BaseProcessFilter implements DependencyExtractorInterface
 {
+    /**
+     * @var string
+     */
     private $dartBin;
 
+    /**
+     * @param string $dartBin
+     */
     public function __construct($dartBin = '/usr/bin/dart2js')
     {
         $this->dartBin = $dartBin;
     }
 
+    /**
+     * @param  AssetInterface    $asset
+     * @throws \RuntimeException
+     */
     public function filterLoad(AssetInterface $asset)
     {
         $input  = tempnam(sys_get_temp_dir(), 'assetic_dart');
         $output = tempnam(sys_get_temp_dir(), 'assetic_dart');
 
-        file_put_contents($input, $asset->getContent());
+        $content = $asset->getContent();
+
+        $sourcePath = $asset->getSourceDirectory();
+
+        $callback = function ($matches) use ($sourcePath, &$content) {
+            if (!$matches['url'] || null === $sourcePath || 'dart:' === substr($matches['url'], 0, 5)) {
+                return;
+            }
+
+            $currentDir = getcwd();
+
+            chdir($sourcePath);
+            $importPath = str_replace('\\', '/', realpath($matches['url']));
+            chdir($currentDir);
+
+            if ('/' !== substr($importPath, 0, 1)) {
+                $importPath = '/' . $importPath;
+            }
+
+            $content = str_replace($matches['url'], $importPath, $content);
+        };
+
+        DartUtils::filterImports($content, $callback);
+
+        file_put_contents($input, $content);
 
         $pb = $this->createProcessBuilder()
             ->add($this->dartBin)
@@ -61,6 +97,40 @@ public function filterLoad(AssetInterface $asset)
         unlink($output);
     }
 
+    /**
+     * @param  AssetFactory                          $factory
+     * @param  string                                $content
+     * @param  null                                  $loadPath
+     * @return array|\Assetic\Asset\AssetInterface[]
+     */
+    public function getChildren(AssetFactory $factory, $content, $loadPath = null)
+    {
+        if (null === $loadPath) {
+            return array();
+        }
+
+        $children = array();
+
+        foreach (DartUtils::extractImports($content) as $reference) {
+            if ('dart:' === substr($reference, 0, 5)) {
+                // skip imports that is not files
+                continue;
+            }
+
+            if (file_exists($file = $loadPath.'/'.$reference)) {
+                $coll = $factory->createAsset($file, array(), array('root' => $loadPath));
+
+                foreach ($coll as $leaf) {
+                    $leaf->ensureFilter($this);
+                    $children[] = $leaf;
+                    break;
+                }
+            }
+        }
+
+        return $children;
+    }
+
     public function filterDump(AssetInterface $asset)
     {
     }

src/Assetic/Util/DartUtils.php

@@ -0,0 +1,23 @@
+<?php
+
+/*
+ * This file is part of the Assetic package, an OpenSky project.
+ *
+ * (c) 2010-2013 OpenSky Project Inc
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Assetic\Util;
+
+/**
+ * Dart Utils.
+ *
+ * @author Pierre du Plessis <pdples@gmail.com>
+ */
+class DartUtils extends CssUtils
+{
+    const REGEX_IMPORTS         = '/import? (\'|"|)(?<url>[^\'"\)\n\r]*)\1\)?;?/';
+    const REGEX_COMMENTS        = '/((?:\/\*[^*]*\*+(?:[^\/][^*]*\*+)*\/)|\/\/[^\n]+)/';
+}

tests/Assetic/Test/Filter/DartFilterTest.php

@@ -12,6 +12,7 @@
 namespace Assetic\Test\Filter;
 
 use Assetic\Asset\StringAsset;
+use Assetic\Asset\FileAsset;
 use Assetic\Filter\DartFilter;
 
 /**
@@ -35,6 +36,19 @@ protected function tearDown()
         $this->filter = null;
     }
 
+    public function testImport()
+    {
+        $asset = new FileAsset(__DIR__.'/fixtures/dart/main.dart');
+        $asset->load();
+
+        $this->filter->filterLoad($asset);
+
+        $this->assertContains(
+            'Generated by dart2js, the Dart to JavaScript compiler.',
+            $asset->getContent()
+        );
+    }
+
     public function testFilterLoad()
     {
         $input = <<<EOM

tests/Assetic/Test/Filter/fixtures/dart/library/library.dart

@@ -0,0 +1,12 @@
+import 'dart:html';
+
+librayFunction() {
+  var msg = query('#msg');
+  var btn = new ButtonElement();
+  var someThing = new Element.a();
+  someThing.href = 'New Cool Link';
+
+  btn.text = 'Click me!';
+  btn.on.click.add((e) => msg.text = 'Dart!');
+  document.body.nodes.add(btn);
+}

tests/Assetic/Test/Filter/fixtures/dart/main.dart

@@ -0,0 +1,5 @@
+import "library/library.dart";
+
+main() {
+  librayFunction();
+}