[5.6] Handle more JSON errors gracefully when JSON_PARTIAL_OUTPUT_ON_…

…ERROR is set

It's fairly common for stack traces to be circular, i.e. they can't be encoded as JSON without limiting the recursion depth somehow. PHP automatically does this if JSON_PARTIAL_OUTPUT_ON_ERROR is true, but we still considered it an error.

By treating JSON_ERROR_RECURSION as okay if JSON_PARTIAL_OUTPUT_ON_ERROR is set we prevent things from blowing up if the user uses a JSON-based exception handler.

Since exceptions thrown in exception handlers are generally a recipe for disaster I added JSON_ERROR_INF_OR_NAN to the list of "acceptable" errors too.

src/Illuminate/Http/JsonResponse.php

@@ -86,9 +86,24 @@ public function setData($data = [])
      */
     protected function hasValidJson($jsonError)
     {
-        return $jsonError === JSON_ERROR_NONE ||
-                ($jsonError === JSON_ERROR_UNSUPPORTED_TYPE &&
-                $this->hasEncodingOption(JSON_PARTIAL_OUTPUT_ON_ERROR));
+        // No error is obviously fine
+        if ($jsonError === JSON_ERROR_NONE) {
+            return true;
+        }
+
+        // If the JSON_PARTIAL_OUTPUT_ON_ERROR option is set, some additional errors are fine
+        // (see https://secure.php.net/manual/en/json.constants.php)
+        if ($this->hasEncodingOption(JSON_PARTIAL_OUTPUT_ON_ERROR)) {
+            $acceptableErrors = [
+                JSON_ERROR_RECURSION,
+                JSON_ERROR_INF_OR_NAN,
+                JSON_ERROR_UNSUPPORTED_TYPE,
+            ];
+
+            return \in_array($jsonError, $acceptableErrors);
+        }
+
+        return false;
     }
 
     /**

tests/Http/HttpJsonResponseTest.php

@@ -92,6 +92,29 @@ public function testJsonErrorResourceWithPartialOutputOnError()
         $this->assertInstanceOf('stdClass', $data);
         $this->assertNull($data->resource);
     }
+
+    public function testJsonErrorRecursionDetectedWithPartialOutputOnError()
+    {
+        $objectA = new \stdClass();
+        $objectB = new \stdClass();
+        $objectA->b = $objectB;
+        $objectB->a = $objectA;
+
+        $response = new \Illuminate\Http\JsonResponse($objectA, 200, [], JSON_PARTIAL_OUTPUT_ON_ERROR);
+        $data = $response->getData();
+
+        $this->assertNotNull($data);
+    }
+
+    public function testJsonErrorInfOrNanWithPartialOutputOnError()
+    {
+        $data = ['product' => NAN];
+
+        $response = new \Illuminate\Http\JsonResponse($data, 200, [], JSON_PARTIAL_OUTPUT_ON_ERROR);
+        $data = $response->getData();
+
+        $this->assertNotNull($data);
+    }
 }
 
 class JsonResponseTestJsonableObject implements Jsonable