Fixing CakeRequest::accepts() where ;q values on Accept header

were not respected.
Fixes #1940

lib/Cake/Network/CakeRequest.php

@@ -605,23 +605,35 @@ public function subdomains($tldLength = 1) {
  *
  * `$this->request->accepts('json');`
  *
+ * This method will order the returned content types by the preference values indicated
+ * by the client.
+ *
  * @param string $type The content type to check for.  Leave null to get all types a client accepts.
  * @return mixed Either an array of all the types the client accepts or a boolean if they accept the
  *   provided type.
  */
 	public function accepts($type = null) {
-		$acceptTypes = explode(',', $this->header('accept'));
-		$acceptTypes = array_map('trim', $acceptTypes);
-		foreach ($acceptTypes as $i => $accepted) {
-			if (strpos($accepted, ';') !== false) {
-				list($accepted) = explode(';', $accepted);
-				$acceptTypes[$i] = $accepted;
+		$accept = array();
+		$header = explode(',', $this->header('accept'));
+		foreach (array_filter(array_reverse($header)) as $value) {
+			$prefPos = strpos($value, ';');
+			if ($prefPos !== false) {
+				$prefValue = (float) substr($value, strpos($value, '=') + 1);
+				$value = trim(substr($value, 0, $prefPos));
+			} else {
+				$prefValue = 1.0;
+				$value = trim($value);
+			}
+			if ($prefValue) {
+				$accept[$value] = $prefValue;
 			}
 		}
+		arsort($accept);
+		$accept = array_keys($accept);
 		if ($type === null) {
-			return $acceptTypes;
+			return $accept;
 		}
-		return in_array($type, $acceptTypes);
+		return in_array($type, $accept);
 	}
 
 /**

lib/Cake/Test/Case/Network/CakeRequestTest.php

@@ -785,7 +785,7 @@ public function testAccepts() {
 
 		$result = $request->accepts();
 		$expected = array(
-			'text/xml', 'application/xml', 'application/xhtml+xml', 'text/html', 'text/plain', 'image/png'
+			'text/xml', 'application/xhtml+xml', 'text/html', 'image/png', 'text/plain', 'application/xml'
 		);
 		$this->assertEquals($expected, $result, 'Content types differ.');
 
@@ -813,6 +813,19 @@ public function testAcceptWithWhitespace() {
 		$this->assertTrue($request->accepts('text/html'));
 	}
 
+/**
+ * Content types from accepts() should respect the client's q preference values.
+ *
+ * @return void
+ */
+	public function testAcceptWithQvalueSorting() {
+		$_SERVER['HTTP_ACCEPT'] = 'text/html;q=0.8,application/json;q=0.7,application/xml;q=1.0';
+		$request = new CakeRequest('/', false);
+		$result = $request->accepts();
+		$expected = array('application/xml', 'text/html', 'application/json');
+		$this->assertEquals($expected, $result);
+	}
+
 /**
  * testBaseUrlAndWebrootWithModRewrite method
  *