[#52] Review prior to merge

- Added method docblocks where missing.
- Added behavior to `json()` method: cast scalars to array prior to attempts to
  serialize.

src/Response/StringResponse.php

@@ -15,12 +15,13 @@
 /**
  * String response factory.
  *
- * A class with helper methods for easily creating proper responses from strings or structured data.
+ * A class with helper methods for easily creating proper responses from
+ * strings or structured data.
  */
 final class StringResponse
 {
     /**
-     * Create a HTML response with the given body text.
+     * Create an HTML response with the given body text.
      *
      * @param string $html The response body content, as a string.
      * @param int $status Status code for the response, if any.
@@ -35,26 +36,50 @@ public static function html($html, $status = 200, array $headers = [])
     /**
      * Create a JSON response with the given array of data.
      *
-     * @param array|\JsonSerializable $data The data to be converted to JSON.
+     * If the data provided is null, an empty ArrayObject is used; if the data
+     * is scalar, it is cast to an array prior to serialization.
+     *
+     * @param mixed $data The data to be converted to JSON.
      * @param int $status Status code for the response, if any.
      * @param array $headers Headers for the response, if any.
      * @return Response
      */
     public static function json($data, $status = 200, array $headers = [])
     {
         if ($data === null) {
+            // Use an ArrayObject to force an empty JSON object.
             $data = new ArrayObject();
         }
 
+        if (is_scalar($data)) {
+            $data = (array) $data;
+        }
+
         $json = json_encode($data, JSON_UNESCAPED_SLASHES);
 
         return static::createResponse($json, $status, $headers, 'application/json');
     }
 
+    /**
+     * This class is non-instantiable.
+     */
     private function __construct()
     {
     }
 
+    /**
+     * Create a Response from the provided information.
+     *
+     * Creates a Response using a php://temp stream, and writes the provided
+     * body to the stream; if non content-type header was provided, the given
+     * $contentType is injected for it.
+     *
+     * @param string $body
+     * @param int $status
+     * @param array $headers
+     * @param string $contentType
+     * @return Response
+     */
     private static function createResponse($body, $status, array $headers, $contentType)
     {
         $response = new Response('php://temp', $status, $headers);

test/Response/StringResponseTest.php

@@ -24,7 +24,7 @@ public function testHtmlConstructor()
 
         $response = StringResponse::html($body, $status, $headers);
         $this->assertInstanceOf('Zend\Diactoros\Response', $response);
-        $this->assertSame($body, $response->getBody()->__toString());
+        $this->assertSame($body, (string) $response->getBody());
         $this->assertEquals(404, $response->getStatusCode());
         $this->assertEquals(['foo-bar'], $response->getHeader('x-custom'));
         $this->assertEquals('text/html', $response->getHeaderLine('content-type'));
@@ -35,17 +35,52 @@ public function testJsonConstructor()
         $data = [
             'nested' => [
                 'json' => [
-                    'tree'
-                ]
-            ]
+                    'tree',
+                ],
+            ],
         ];
         $json = '{"nested":{"json":["tree"]}}';
 
         $response = StringResponse::json($data);
         $this->assertInstanceOf('Zend\Diactoros\Response', $response);
-        $this->assertSame($json, $response->getBody()->__toString());
         $this->assertEquals(200, $response->getStatusCode());
         $this->assertEquals('application/json', $response->getHeaderLine('content-type'));
+        $this->assertSame($json, (string) $response->getBody());
+    }
+
+    public function testNullValuePassedToJsonRendersEmptyJSONObject()
+    {
+        $response = StringResponse::json(null);
+        $this->assertInstanceOf('Zend\Diactoros\Response', $response);
+        $this->assertEquals(200, $response->getStatusCode());
+        $this->assertEquals('application/json', $response->getHeaderLine('content-type'));
+        $this->assertSame('{}', (string) $response->getBody());
+    }
+
+    public function scalarValuesForJSON()
+    {
+        return [
+            'false'        => [false],
+            'true'         => [true],
+            'zero'         => [0],
+            'int'          => [1],
+            'zero-float'   => [0.0],
+            'float'        => [1.1],
+            'empty-string' => [''],
+            'string'       => ['string'],
+        ];
+    }
+
+    /**
+     * @dataProvider scalarValuesForJSON
+     */
+    public function testScalarValuePassedToJsonRendersValueWithinJSONArray($value)
+    {
+        $response = StringResponse::json($value);
+        $this->assertInstanceOf('Zend\Diactoros\Response', $response);
+        $this->assertEquals(200, $response->getStatusCode());
+        $this->assertEquals('application/json', $response->getHeaderLine('content-type'));
+        $this->assertSame(json_encode([$value], JSON_UNESCAPED_SLASHES), (string) $response->getBody());
     }
 
     public function testContentTypeCanBeOverwritten()
@@ -54,7 +89,7 @@ public function testContentTypeCanBeOverwritten()
         $json = '{}';
 
         $response = StringResponse::json($data, 200, ['content-type' => 'foo/json']);
-        $this->assertSame($json, $response->getBody()->__toString());
+        $this->assertSame($json, (string) $response->getBody());
         $this->assertEquals('foo/json', $response->getHeaderLine('content-type'));
     }
 }