Allow Streams to be instantiated using GD resources

docs/book/v2/api.md

@@ -174,10 +174,11 @@ prefixed with `with` and `without` — all return a new instance with the ch
 `Laminas\Diactoros\Stream` is an implementation of
 [`Psr\Http\Message\StreamInterface`](https://github.com/php-fig/http-message/blob/master/src/StreamInterface.php),
 and provides a number of facilities around manipulating the composed PHP stream resource. The
-constructor accepts a stream, which may be either:
+constructor accepts a stream, which may be one of:
 
-- a stream identifier; e.g., `php://input`, a filename, etc.
-- a PHP stream resource
+- A stream identifier; e.g., `php://input`, a filename, etc.
+- A PHP stream resource; or
+- A GD resource
 
 If a stream identifier is provided, an optional second parameter may be provided, the file mode by
 which to `fopen` the stream.

src/Stream.php

@@ -40,6 +40,11 @@
  */
 class Stream implements StreamInterface
 {
+    /**
+     * A list of allowed stream resource types that are allowed to instantiate a Stream
+     */
+    private const ALLOWED_STREAM_RESOURCE_TYPES = ['gd', 'stream'];
+
     /**
      * @var resource|null
      */
@@ -345,7 +350,7 @@ private function setStream($stream, string $mode = 'r') : void
             throw new Exception\InvalidArgumentException('Invalid stream reference provided');
         }
 
-        if (! is_resource($resource) || 'stream' !== get_resource_type($resource)) {
+        if (! $this->isValidStreamResourceType($resource)) {
             throw new Exception\InvalidArgumentException(
                 'Invalid stream provided; must be a string stream identifier or stream resource'
             );
@@ -357,4 +362,17 @@ private function setStream($stream, string $mode = 'r') : void
 
         $this->resource = $resource;
     }
+
+    /**
+     * Determine if a resource is one of the resource types allowed to instantiate a Stream
+     *
+     * @param resource $resource Stream resource.
+     */
+    private function isValidStreamResourceType($resource): bool
+    {
+        return (
+            is_resource($resource) &&
+            in_array(get_resource_type($resource), self::ALLOWED_STREAM_RESOURCE_TYPES, true)
+        );
+    }
 }

src/StreamFactory.php

@@ -46,11 +46,6 @@ public function createStreamFromFile(string $file, string $mode = 'r') : StreamI
      */
     public function createStreamFromResource($resource) : StreamInterface
     {
-        if (! is_resource($resource) || 'stream' !== get_resource_type($resource)) {
-            throw new Exception\InvalidArgumentException(
-                'Invalid stream provided; must be a stream resource'
-            );
-        }
         return new Stream($resource);
     }
 }

test/StreamTest.php

@@ -72,6 +72,13 @@ public function testCanInstantiteWithStreamResource()
         $this->assertInstanceOf(Stream::class, $stream);
     }
 
+    public function testCanInstantiateWithGDResource()
+    {
+        $resource = imagecreate(1, 1);
+        $stream   = new Stream($resource);
+        $this->assertInstanceOf(Stream::class, $stream);
+    }
+
     public function testIsReadableReturnsFalseIfStreamIsNotReadable()
     {
         $this->tmpnam = tempnam(sys_get_temp_dir(), 'diac');