diff --git a/PHPUnit/Framework/Constraint.php b/PHPUnit/Framework/Constraint.php
index 99f0252b715..0c59c1b1a01 100644
--- a/PHPUnit/Framework/Constraint.php
+++ b/PHPUnit/Framework/Constraint.php
@@ -90,14 +90,16 @@ abstract public function evaluate($other);
      */
     public function fail($other, $description, $not = FALSE)
     {
-        if (!empty($description)) {
-            $description .= "\n";
-        }
+        throw new PHPUnit_Framework_ExpectationFailedException(
+          $this->failureDescription($other, $description, $not)
+        );
+    }
 
+    protected function failureDescription($other, $description, $not)
+    {
         $failureDescription = sprintf(
-          '%sFailed asserting that %s %s.',
+          'Failed asserting that %s %s.',
 
-           $description,
            PHPUnit_Util_Type::toString($other),
            $this->toString()
         );
@@ -106,9 +108,11 @@ public function fail($other, $description, $not = FALSE)
             $failureDescription = self::negate($failureDescription);
         }
 
-        throw new PHPUnit_Framework_ExpectationFailedException(
-          $failureDescription
-        );
+        if (!empty($description)) {
+            $failureDescription = $description . "\n" . $failureDescription;
+        }
+
+        return $failureDescription;
     }
 
     public static function negate($string)
@@ -122,11 +126,11 @@ public static function negate($string)
             'matches '
           ),
           array(
-            'not contains ',
-            'not exists ',
-            'has not ',
+            'does not contain ',
+            'does not exist ',
+            'does not have ',
             'is not ',
-            'not matches '
+            'does not match '
           ),
           $string
         );
diff --git a/PHPUnit/Framework/Constraint/FileExists.php b/PHPUnit/Framework/Constraint/FileExists.php
index 2e3bc88ebaf..67a78ed5483 100644
--- a/PHPUnit/Framework/Constraint/FileExists.php
+++ b/PHPUnit/Framework/Constraint/FileExists.php
@@ -89,17 +89,22 @@ public function evaluate($other)
      */
     public function fail($other, $description, $not = FALSE)
     {
+        $failureDescription = sprintf(
+          'Failed asserting that file "%s" exists.',
+
+           $other
+        );
+
+        if ($not) {
+            $failureDescription = self::negate($failureDescription);
+        }
+
         if (!empty($description)) {
-            $description .= "\n";
+            $failureDescription = $description . "\n" . $failureDescription;
         }
 
         throw new PHPUnit_Framework_ExpectationFailedException(
-          sprintf(
-            '%sFailed asserting that file "%s" exists.',
-
-             $description,
-             $other
-          )
+          $failureDescription
         );
     }
 
diff --git a/PHPUnit/Framework/Constraint/IsEqual.php b/PHPUnit/Framework/Constraint/IsEqual.php
index e0763f82831..bbe530a051b 100644
--- a/PHPUnit/Framework/Constraint/IsEqual.php
+++ b/PHPUnit/Framework/Constraint/IsEqual.php
@@ -106,16 +106,10 @@ public function evaluate($other)
      */
     public function fail($other, $description, $not = FALSE)
     {
-        if (!empty($description)) {
-            $description .= "\n";
-        }
-
-        $failureDescription = sprintf(
-          '%sFailed asserting that %s %s.',
-
-           $description,
-           PHPUnit_Util_Type::toString($other),
-           $this->toString()
+        $failureDescription = $this->failureDescription(
+          $other,
+          $description,
+          $not
         );
 
         if (!$not) {
@@ -124,8 +118,6 @@ public function fail($other, $description, $not = FALSE)
               PHPUnit_Framework_ComparisonFailure::diffEqual($this->value, $other)
             );
         } else {
-            $failureDescription = self::negate($failureDescription);
-
             throw new PHPUnit_Framework_ExpectationFailedException(
               $failureDescription
             );
diff --git a/PHPUnit/Framework/Constraint/IsIdentical.php b/PHPUnit/Framework/Constraint/IsIdentical.php
index 916b831ed1b..9a11dc485cd 100644
--- a/PHPUnit/Framework/Constraint/IsIdentical.php
+++ b/PHPUnit/Framework/Constraint/IsIdentical.php
@@ -101,16 +101,10 @@ public function evaluate($other)
      */
     public function fail($other, $description, $not = FALSE)
     {
-        if (!empty($description)) {
-            $description .= "\n";
-        }
-
-        $failureDescription = sprintf(
-          '%sFailed asserting that %s %s.',
-
-           $description,
-           PHPUnit_Util_Type::toString($other),
-           $this->toString()
+        $failureDescription = $this->failureDescription(
+          $other,
+          $description,
+          $not
         );
 
         if (!$not) {
@@ -120,7 +114,7 @@ public function fail($other, $description, $not = FALSE)
             );
         } else {
             throw new PHPUnit_Framework_ExpectationFailedException(
-              $failureDescription
+              self::negate($failureDescription)
             );
         }
     }