bug symfony#15718 Fix that two DirectoryResources with different patterns would be deduplicated (mpdude)

This PR was submitted for the 2.8 branch but it was merged into the 2.3 branch instead (closes symfony#15718).

Discussion
----------

Fix that two DirectoryResources with different patterns would be deduplicated

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

ResourceInterface::__toString is mainly important because in various places, array_uniqe() is called to perform a de-duplication of resources and will use the string representation for objects.

Thus, we need to take care that if DirectoryResources apply different patterns they must be kept after array_unique calls.

Commits
-------

2b36ac5 Fix that two DirectoryResources with different patterns would be deduplicated

Author: fabpot

src/Symfony/Component/Config/Resource/DirectoryResource.php

@@ -38,7 +38,7 @@ public function __construct($resource, $pattern = null)
      */
     public function __toString()
     {
-        return (string) $this->resource;
+        return md5(serialize(array($this->resource, $this->pattern)));
     }
 
     /**

src/Symfony/Component/Config/Tests/Resource/DirectoryResourceTest.php

@@ -54,7 +54,6 @@ public function testGetResource()
     {
         $resource = new DirectoryResource($this->directory);
         $this->assertSame($this->directory, $resource->getResource(), '->getResource() returns the path to the resource');
-        $this->assertSame($this->directory, (string) $resource, '->__toString() returns the path to the resource');
     }
 
     public function testGetPattern()
@@ -87,6 +86,13 @@ public function testIsFreshNewFile()
         $this->assertFalse($resource->isFresh(time() + 10), '->isFresh() returns false if a new file is added');
     }
 
+    public function testIsFreshNewFileWithDifferentPattern()
+    {
+        $resource = new DirectoryResource($this->directory, '/.xml$/');
+        touch($this->directory.'/new.yaml', time() + 20);
+        $this->assertTrue($resource->isFresh(time() + 10), '->isFresh() returns true if a new file with a non-matching pattern is added');
+    }
+
     public function testIsFreshDeleteFile()
     {
         $resource = new DirectoryResource($this->directory);
@@ -149,4 +155,12 @@ public function testSerializeUnserialize()
         $this->assertSame($this->directory, $resource->getResource());
         $this->assertSame('/\.(foo|xml)$/', $resource->getPattern());
     }
+
+    public function testResourcesWithDifferentPatternsAreDifferent()
+    {
+        $resourceA = new DirectoryResource($this->directory, '/.xml$/');
+        $resourceB = new DirectoryResource($this->directory, '/.yaml$/');
+
+        $this->assertEquals(2, count(array_unique(array($resourceA, $resourceB))));
+    }
 }