Google\Cloud\Tests\Snippets\Vision\ImageTest::testImageString PHP Method

    public function testImageString()
    {
        $snippet = $this->snippetFromClass(Image::class, 'string');
        $snippet->setLine(5, '$imageData = \'foo\';');
        $res = $snippet->invoke('image');
        $this->assertInstanceOf(Image::class, $res->returnVal());
    }