Refactored Basz's code a little. Added docblocks + unit tests

Author: Freeaqingme

src/Header/AbstractAccept.php

@@ -302,10 +302,10 @@ public function match($matchAgainst)
         foreach ($this->getPrioritized() as $left) {
             foreach ($matchAgainst as $right) {
                 if ($right->type == '*' || $left->type == '*') {
-                    if ($res = $this->matchAcceptParams($left, $right)) {
-                        $res->matchedAgainst = $right;
+                    if ($this->matchAcceptParams($left, $right)) {
+                        $left->setMatchedAgainst($right);
 
-                        return $res;
+                        return $left;
                     }
                 }
 
@@ -315,10 +315,10 @@ public function match($matchAgainst)
                             ($left->format == $right->format ||
                                     $right->format == '*' || $left->format == '*')))
                     {
-                        if ($res = $this->matchAcceptParams($left, $right)) {
-                            $res->matchedAgainst = $right;
+                        if ($this->matchAcceptParams($left, $right)) {
+                            $left->setMatchedAgainst($right);
 
-                            return $res;
+                            return $left;
                         }
                     }
                 }

src/Header/Accept/FieldValuePart/AbstractFieldValuePart.php

@@ -27,6 +27,12 @@ abstract class AbstractFieldValuePart
      */
     private $internalValues;
 
+    /**
+     * A Field Value Part this Field Value Part matched against.
+     * @var AbstractFieldValuePart
+     */
+    protected $matchedPart;
+
     /**
      *
      * @param object $internalValues
@@ -36,6 +42,28 @@ public function __construct($internalValues)
         $this->internalValues = $internalValues;
     }
 
+    /**
+     * Set a Field Value Part this Field Value Part matched against.
+     *
+     * @param AbstractFieldValuePart $matchedPart
+     * return AbstractFieldValuePart provides fluent interface
+     */
+    public function setMatchedAgainst(AbstractFieldValuePart $matchedPart)
+    {
+        $this->matchedPart = $matchedPart;
+        return $this;
+    }
+
+    /**
+     * Get a Field Value Part this Field Value Part matched against.
+     *
+     * return AbstractFieldValuePart|null
+     */
+    public function getMatchedAgainst()
+    {
+        return $this->matchedPart;
+    }
+
     /**
      *
      * @return object

test/Header/AcceptTest.php

@@ -193,6 +193,38 @@ public function testParsingAndAssemblingQuotedStrings()
     }
 
 
+    public function testMatchReturnsMatchedAgainstObject()
+    {
+        $acceptStr = 'Accept: text/html;q=1; version=23; level=5, text/json;level=1,' .
+                'text/xml;level=2;q=0.4';
+        $acceptHeader = Accept::fromString($acceptStr);
+
+        $res = $acceptHeader->match('text/html; _randomValue=foobar');
+        $this->assertInstanceOf(
+                'Zend\Http\Header\Accept\FieldValuePart\AbstractFieldValuePart',
+                $res->getMatchedAgainst()
+        );
+        $this->assertEquals(
+                'foobar',
+                $res->getMatchedAgainst()->getParams()->_randomValue
+        );
+
+        $acceptStr = 'Accept: */*; ';
+        $acceptHeader = Accept::fromString($acceptStr);
+
+        $res = $acceptHeader->match('text/html; _foo=bar');
+        $this->assertInstanceOf(
+                'Zend\Http\Header\Accept\FieldValuePart\AbstractFieldValuePart',
+                $res->getMatchedAgainst()
+        );
+
+        $this->assertEquals(
+                'bar',
+                $res->getMatchedAgainst()->getParams()->_foo
+        );
+    }
+
+
     public function testVersioning()
     {
         $acceptStr = 'Accept: text/html;q=1; version=23; level=5, text/json;level=1,' .