ToolkitGdTest.php

<?php

namespace Drupal\KernelTests\Core\Image;

use Drupal\Core\File\FileSystemInterface;
use Drupal\Core\Image\ImageInterface;
use Drupal\KernelTests\KernelTestBase;

/**
 * Tests for the GD image toolkit.
 *
 * @coversDefaultClass \Drupal\system\Plugin\ImageToolkit\GDToolkit
 * @group Image
 * @requires extension gd
 */
class ToolkitGdTest extends KernelTestBase {
    
    /**
     * Colors that are used in testing.
     */
    protected const BLACK = [
        0,
        0,
        0,
        0,
    ];
    protected const RED = [
        255,
        0,
        0,
        0,
    ];
    protected const GREEN = [
        0,
        255,
        0,
        0,
    ];
    protected const BLUE = [
        0,
        0,
        255,
        0,
    ];
    protected const YELLOW = [
        255,
        255,
        0,
        0,
    ];
    protected const WHITE = [
        255,
        255,
        255,
        0,
    ];
    protected const TRANSPARENT = [
        0,
        0,
        0,
        127,
    ];
    protected const FUCHSIA = [
        255,
        0,
        255,
        0,
    ];
    protected const ROTATE_TRANSPARENT = [
        255,
        255,
        255,
        127,
    ];
    
    /**
     * The image factory service.
     *
     * @var \Drupal\Core\Image\ImageFactory
     */
    protected $imageFactory;
    
    /**
     * A directory where test image files can be saved to.
     *
     * @var string
     */
    protected $directory;
    
    /**
     * {@inheritdoc}
     */
    protected static $modules = [
        'system',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        parent::setUp();
        $this->installConfig([
            'system',
        ]);
        // Set the image factory service.
        $this->imageFactory = $this->container
            ->get('image.factory');
        $this->assertEquals('gd', $this->imageFactory
            ->getToolkitId(), 'The image factory is set to use the \'gd\' image toolkit.');
        // Prepare a directory for test file results.
        $this->directory = 'public://imagetest';
        \Drupal::service('file_system')->prepareDirectory($this->directory, FileSystemInterface::CREATE_DIRECTORY);
    }
    
    /**
     * Assert two colors are equal by RGBA, net of full transparency.
     *
     * @param int[] $expected
     *   The expected RGBA array.
     * @param int[] $actual
     *   The actual RGBA array.
     * @param int $tolerance
     *   The acceptable difference between the colors.
     * @param string $message
     *   The assertion message.
     */
    protected function assertColorsAreEqual(array $expected, array $actual, int $tolerance, string $message = '') : void {
        // Fully transparent colors are equal, regardless of RGB.
        if ($actual[3] == 127 && $expected[3] == 127) {
            return;
        }
        $distance = pow($actual[0] - $expected[0], 2) + pow($actual[1] - $expected[1], 2) + pow($actual[2] - $expected[2], 2) + pow($actual[3] - $expected[3], 2);
        $this->assertLessThanOrEqual($tolerance, $distance, $message . " - Actual: {" . implode(',', $actual) . "}, Expected: {" . implode(',', $expected) . "}, Distance: " . $distance . ", Tolerance: " . $tolerance);
    }
    
    /**
     * Function for finding a pixel's RGBa values.
     */
    public function getPixelColor(ImageInterface $image, int $x, int $y) : array {
        $toolkit = $image->getToolkit();
        $color_index = imagecolorat($toolkit->getResource(), $x, $y);
        $transparent_index = imagecolortransparent($toolkit->getResource());
        if ($color_index == $transparent_index) {
            return [
                0,
                0,
                0,
                127,
            ];
        }
        return array_values(imagecolorsforindex($toolkit->getResource(), $color_index));
    }
    
    /**
     * Data provider for ::testManipulations().
     */
    public function providerTestImageFiles() : array {
        // Typically the corner colors will be unchanged. These colors are in the
        // order of top-left, top-right, bottom-right, bottom-left.
        $default_corners = [
            static::RED,
            static::GREEN,
            static::BLUE,
            static::TRANSPARENT,
        ];
        // Setup a list of tests to perform on each type.
        $test_cases = [
            'resize' => [
                'operation' => 'resize',
                'arguments' => [
                    'width' => 20,
                    'height' => 10,
                ],
                'width' => 20,
                'height' => 10,
                'corners' => $default_corners,
            ],
            'scale_x' => [
                'operation' => 'scale',
                'arguments' => [
                    'width' => 20,
                ],
                'width' => 20,
                'height' => 10,
                'corners' => $default_corners,
            ],
            'scale_y' => [
                'operation' => 'scale',
                'arguments' => [
                    'height' => 10,
                ],
                'width' => 20,
                'height' => 10,
                'corners' => $default_corners,
            ],
            'upscale_x' => [
                'operation' => 'scale',
                'arguments' => [
                    'width' => 80,
                    'upscale' => TRUE,
                ],
                'width' => 80,
                'height' => 40,
                'corners' => $default_corners,
            ],
            'upscale_y' => [
                'operation' => 'scale',
                'arguments' => [
                    'height' => 40,
                    'upscale' => TRUE,
                ],
                'width' => 80,
                'height' => 40,
                'corners' => $default_corners,
            ],
            'crop' => [
                'operation' => 'crop',
                'arguments' => [
                    'x' => 12,
                    'y' => 4,
                    'width' => 16,
                    'height' => 12,
                ],
                'width' => 16,
                'height' => 12,
                'corners' => array_fill(0, 4, static::WHITE),
            ],
            'scale_and_crop' => [
                'operation' => 'scale_and_crop',
                'arguments' => [
                    'width' => 10,
                    'height' => 8,
                ],
                'width' => 10,
                'height' => 8,
                'corners' => array_fill(0, 4, static::BLACK),
            ],
            'convert_jpg' => [
                'operation' => 'convert',
                'width' => 40,
                'height' => 20,
                'arguments' => [
                    'extension' => 'jpeg',
                ],
                'corners' => $default_corners,
            ],
            'convert_gif' => [
                'operation' => 'convert',
                'width' => 40,
                'height' => 20,
                'arguments' => [
                    'extension' => 'gif',
                ],
                'corners' => $default_corners,
            ],
            'convert_png' => [
                'operation' => 'convert',
                'width' => 40,
                'height' => 20,
                'arguments' => [
                    'extension' => 'png',
                ],
                'corners' => $default_corners,
            ],
            'convert_webp' => [
                'operation' => 'convert',
                'width' => 40,
                'height' => 20,
                'arguments' => [
                    'extension' => 'webp',
                ],
                'corners' => $default_corners,
            ],
        ];
        // Systems using non-bundled GD2 may miss imagerotate(). Test if available.
        if (function_exists('imagerotate')) {
            $test_cases += [
                'rotate_5' => [
                    'operation' => 'rotate',
                    // Fuchsia background.
'arguments' => [
                        'degrees' => 5,
                        'background' => '#FF00FF',
                    ],
                    // @todo Re-enable dimensions' check once
                    //   https://www.drupal.org/project/drupal/issues/2921123 is resolved.
                    // 'width' => 41,
                    // 'height' => 23,
'corners' => array_fill(0, 4, static::FUCHSIA),
                ],
                'rotate_transparent_5' => [
                    'operation' => 'rotate',
                    'arguments' => [
                        'degrees' => 5,
                    ],
                    // @todo Re-enable dimensions' check once
                    //   https://www.drupal.org/project/drupal/issues/2921123 is resolved.
                    // 'width' => 41,
                    // 'height' => 23,
'corners' => array_fill(0, 4, static::ROTATE_TRANSPARENT),
                ],
                'rotate_90' => [
                    'operation' => 'rotate',
                    // Fuchsia background.
'arguments' => [
                        'degrees' => 90,
                        'background' => '#FF00FF',
                    ],
                    'width' => 20,
                    'height' => 40,
                    'corners' => [
                        static::TRANSPARENT,
                        static::RED,
                        static::GREEN,
                        static::BLUE,
                    ],
                ],
                'rotate_transparent_90' => [
                    'operation' => 'rotate',
                    'arguments' => [
                        'degrees' => 90,
                    ],
                    'width' => 20,
                    'height' => 40,
                    'corners' => [
                        static::TRANSPARENT,
                        static::RED,
                        static::GREEN,
                        static::BLUE,
                    ],
                ],
            ];
        }
        // Systems using non-bundled GD2 may miss imagefilter(). Test if available.
        if (function_exists('imagefilter')) {
            $test_cases += [
                'desaturate' => [
                    'operation' => 'desaturate',
                    'arguments' => [],
                    'height' => 20,
                    'width' => 40,
                    // Grayscale corners are a bit funky. Each of the corners are a shade of
                    // gray. The values of these were determined simply by looking at the
                    // final image to see what desaturated colors end up being.
'corners' => [
                        array_fill(0, 3, 76) + [
                            3 => 0,
                        ],
                        array_fill(0, 3, 149) + [
                            3 => 0,
                        ],
                        array_fill(0, 3, 29) + [
                            3 => 0,
                        ],
                        array_fill(0, 3, 225) + [
                            3 => 127,
                        ],
                    ],
                ],
            ];
        }
        $ret = [];
        foreach ([
            'image-test.png',
            'image-test.gif',
            'image-test-no-transparency.gif',
            'image-test.jpg',
            'img-test.webp',
        ] as $file_name) {
            foreach ($test_cases as $test_case => $values) {
                $operation = $values['operation'];
                $arguments = $values['arguments'];
                unset($values['operation'], $values['arguments']);
                $ret[] = [
                    $file_name,
                    $test_case,
                    $operation,
                    $arguments,
                    $values,
                ];
            }
        }
        return $ret;
    }
    
    /**
     * Tests height, width and color for the corners for the final images.
     *
     * Since PHP can't visually check that our images have been manipulated
     * properly, build a list of expected color values for each of the corners and
     * the expected height and widths for the final images.
     *
     * @dataProvider providerTestImageFiles
     */
    public function testManipulations(string $file_name, string $test_case, string $operation, array $arguments, array $expected) : void {
        // Load up a fresh image.
        $image = $this->imageFactory
            ->get('core/tests/fixtures/files/' . $file_name);
        $toolkit = $image->getToolkit();
        $this->assertTrue($image->isValid());
        $image_original_type = $image->getToolkit()
            ->getType();
        $this->assertTrue(imageistruecolor($toolkit->getResource()), "Image '{$file_name}' after load should be a truecolor image, but it is not.");
        // Perform our operation.
        $image->apply($operation, $arguments);
        // Flush Image object to disk storage.
        $file_path = $this->directory . '/' . $test_case . image_type_to_extension($image->getToolkit()
            ->getType());
        $image->save($file_path);
        // Check that the both the GD object and the Image object have an accurate
        // record of the dimensions.
        if (isset($expected['height']) && isset($expected['width'])) {
            $this->assertSame($expected['height'], imagesy($toolkit->getResource()), "Image '{$file_name}' after '{$test_case}' should have a proper height.");
            $this->assertSame($expected['width'], imagesx($toolkit->getResource()), "Image '{$file_name}' after '{$test_case}' should have a proper width.");
            $this->assertSame($expected['height'], $image->getHeight(), "Image '{$file_name}' after '{$test_case}' should have a proper height.");
            $this->assertSame($expected['width'], $image->getWidth(), "Image '{$file_name}' after '{$test_case}' should have a proper width.");
        }
        // Now check each of the corners to ensure color correctness.
        foreach ($expected['corners'] as $key => $expected_color) {
            // The test gif that does not have transparency color set is a
            // special case.
            if ($file_name === 'image-test-no-transparency.gif') {
                if ($test_case == 'desaturate') {
                    // For desaturating, keep the expected color from the test
                    // data, but set alpha channel to fully opaque.
                    $expected_color[3] = 0;
                }
                elseif ($expected_color === static::TRANSPARENT) {
                    // Set expected pixel to yellow where the others have
                    // transparent.
                    $expected_color = static::YELLOW;
                }
            }
            // Get the location of the corner.
            switch ($key) {
                case 0:
                    $x = 0;
                    $y = 0;
                    break;
                case 1:
                    $x = $image->getWidth() - 1;
                    $y = 0;
                    break;
                case 2:
                    $x = $image->getWidth() - 1;
                    $y = $image->getHeight() - 1;
                    break;
                case 3:
                    $x = 0;
                    $y = $image->getHeight() - 1;
                    break;
            }
            $actual_color = $this->getPixelColor($image, $x, $y);
            // If image cannot handle transparent colors, skip the pixel color test.
            if ($actual_color[3] === 0 && $expected_color[3] === 127) {
                continue;
            }
            // JPEG has small differences in color after processing.
            $tolerance = $image_original_type === IMAGETYPE_JPEG ? 3 : 0;
            $this->assertColorsAreEqual($expected_color, $actual_color, $tolerance, "Image '{$file_name}' object after '{$test_case}' action has the correct color placement at corner '{$key}'");
        }
        // Check that saved image reloads without raising PHP errors.
        $image_reloaded = $this->imageFactory
            ->get($file_path);
        if (PHP_VERSION_ID >= 80000) {
            $this->assertInstanceOf(\GDImage::class, $image_reloaded->getToolkit()
                ->getResource());
        }
        else {
            $this->assertIsResource($image_reloaded->getToolkit()
                ->getResource());
            $this->assertSame(get_resource_type($image_reloaded->getToolkit()
                ->getResource()), 'gd');
        }
    }
    
    /**
     * @covers ::getSupportedExtensions
     * @covers ::extensionToImageType
     */
    public function testSupportedExtensions() : void {
        // Test the list of supported extensions.
        $expected_extensions = [
            'png',
            'gif',
            'jpeg',
            'jpg',
            'jpe',
            'webp',
        ];
        $this->assertEqualsCanonicalizing($expected_extensions, $this->imageFactory
            ->getSupportedExtensions());
        // Test that the supported extensions map to correct internal GD image
        // types.
        $expected_image_types = [
            'png' => IMAGETYPE_PNG,
            'gif' => IMAGETYPE_GIF,
            'jpeg' => IMAGETYPE_JPEG,
            'jpg' => IMAGETYPE_JPEG,
            'jpe' => IMAGETYPE_JPEG,
            'webp' => IMAGETYPE_WEBP,
        ];
        $image = $this->imageFactory
            ->get();
        foreach ($expected_image_types as $extension => $expected_image_type) {
            $this->assertSame($expected_image_type, $image->getToolkit()
                ->extensionToImageType($extension));
        }
    }
    
    /**
     * Data provider for ::testCreateImageFromScratch().
     */
    public function providerSupportedImageTypes() : array {
        return [
            [
                IMAGETYPE_PNG,
            ],
            [
                IMAGETYPE_GIF,
            ],
            [
                IMAGETYPE_JPEG,
            ],
            [
                IMAGETYPE_WEBP,
            ],
        ];
    }
    
    /**
     * Tests that GD functions for the image type are available.
     *
     * @dataProvider providerSupportedImageTypes
     */
    public function testGdFunctionsExist(int $type) : void {
        $extension = image_type_to_extension($type, FALSE);
        $this->assertTrue(function_exists("imagecreatefrom{$extension}"), "imagecreatefrom{$extension} should exist.");
        $this->assertTrue(function_exists("image{$extension}"), "image{$extension} should exist.");
    }
    
    /**
     * Tests creation of image from scratch, and saving to storage.
     *
     * @dataProvider providerSupportedImageTypes
     */
    public function testCreateImageFromScratch(int $type) : void {
        // Build an image from scratch.
        $image = $this->imageFactory
            ->get();
        $image->createNew(50, 20, image_type_to_extension($type, FALSE), '#ffff00');
        $file = 'from_null' . image_type_to_extension($type);
        $file_path = $this->directory . '/' . $file;
        $this->assertSame(50, $image->getWidth());
        $this->assertSame(20, $image->getHeight());
        $this->assertSame(image_type_to_mime_type($type), $image->getMimeType());
        $this->assertTrue($image->save($file_path), "Image '{$file}' should have been saved successfully, but it has not.");
        // Reload and check saved image.
        $image_reloaded = $this->imageFactory
            ->get($file_path);
        $this->assertTrue($image_reloaded->isValid());
        $this->assertSame(50, $image_reloaded->getWidth());
        $this->assertSame(20, $image_reloaded->getHeight());
        $this->assertSame(image_type_to_mime_type($type), $image_reloaded->getMimeType());
        if ($image_reloaded->getToolkit()
            ->getType() == IMAGETYPE_GIF) {
            $this->assertSame('#ffff00', $image_reloaded->getToolkit()
                ->getTransparentColor(), "Image '{$file}' after reload should have color channel set to #ffff00, but it has not.");
        }
        else {
            $this->assertNull($image_reloaded->getToolkit()
                ->getTransparentColor(), "Image '{$file}' after reload should have no color channel set, but it has.");
        }
    }
    
    /**
     * Tests failures of the 'create_new' operation.
     */
    public function testCreateNewFailures() : void {
        $image = $this->imageFactory
            ->get();
        $image->createNew(-50, 20);
        $this->assertFalse($image->isValid(), 'CreateNew with negative width fails.');
        $image->createNew(50, 20, 'foo');
        $this->assertFalse($image->isValid(), 'CreateNew with invalid extension fails.');
        $image->createNew(50, 20, 'gif', '#foo');
        $this->assertFalse($image->isValid(), 'CreateNew with invalid color hex string fails.');
        $image->createNew(50, 20, 'gif', '#ff0000');
        $this->assertTrue($image->isValid(), 'CreateNew with valid arguments validates the Image.');
    }
    
    /**
     * Tests that GD resources are freed from memory.
     *
     * @todo Remove the method for PHP 8.0+ https://www.drupal.org/node/3179058
     */
    public function testResourceDestruction() {
        if (PHP_VERSION_ID >= 80000) {
            $this->markTestSkipped('In PHP8 resources are no longer used. \\GdImage objects are used instead. These will be garbage collected like the regular objects they are.');
        }
        // Test that an Image object going out of scope releases its GD resource.
        $image = $this->imageFactory
            ->get('core/tests/fixtures/files/image-test.png');
        $res = $image->getToolkit()
            ->getResource();
        $this->assertIsResource($res);
        $image = NULL;
        // @todo In https://www.drupal.org/node/3133236 convert this to
        //   $this->assertIsNotResource($res).
        $this->assertFalse(is_resource($res), 'Image resource was destroyed after losing scope.');
        // Test that 'create_new' operation does not leave orphaned GD resources.
        $image = $this->imageFactory
            ->get('core/tests/fixtures/files/image-test.png');
        $old_res = $image->getToolkit()
            ->getResource();
        // Check if resource has been created successfully.
        $this->assertIsResource($old_res);
        $image->createNew(20, 20);
        $new_res = $image->getToolkit()
            ->getResource();
        // Check if the original resource has been destroyed.
        // @todo In https://www.drupal.org/node/3133236 convert this to
        //   $this->assertIsNotResource($old_res).
        $this->assertFalse(is_resource($old_res));
        // Check if a new resource has been created successfully.
        $this->assertIsResource($new_res);
    }
    
    /**
     * Tests for GIF images with transparency.
     */
    public function testGifTransparentImages() : void {
        // Test loading an indexed GIF image with transparent color set.
        // Color at top-right pixel should be fully transparent.
        $file = 'image-test-transparent-indexed.gif';
        $image = $this->imageFactory
            ->get('core/tests/fixtures/files/' . $file);
        $resource = $image->getToolkit()
            ->getResource();
        $color_index = imagecolorat($resource, $image->getWidth() - 1, 0);
        $color = array_values(imagecolorsforindex($resource, $color_index));
        $this->assertEquals(static::ROTATE_TRANSPARENT, $color, "Image {$file} after load has full transparent color at corner 1.");
        // Test deliberately creating a GIF image with no transparent color set.
        // Color at top-right pixel should be fully transparent while in memory,
        // fully opaque after flushing image to file.
        $file = 'image-test-no-transparent-color-set.gif';
        $file_path = $this->directory . '/' . $file;
        // Create image.
        $image = $this->imageFactory
            ->get();
        $image->createNew(50, 20, 'gif', NULL);
        $resource = $image->getToolkit()
            ->getResource();
        $color_index = imagecolorat($resource, $image->getWidth() - 1, 0);
        $color = array_values(imagecolorsforindex($resource, $color_index));
        $this->assertEquals(static::ROTATE_TRANSPARENT, $color, "New GIF image with no transparent color set after creation has full transparent color at corner 1.");
        // Save image.
        $this->assertTrue($image->save($file_path), "New GIF image {$file} was saved.");
        // Reload image.
        $image_reloaded = $this->imageFactory
            ->get($file_path);
        $resource = $image_reloaded->getToolkit()
            ->getResource();
        $color_index = imagecolorat($resource, $image_reloaded->getWidth() - 1, 0);
        $color = array_values(imagecolorsforindex($resource, $color_index));
        // Check explicitly for alpha == 0 as the rest of the color has been
        // compressed and may have slight difference from full white.
        $this->assertEquals(0, $color[3], "New GIF image {$file} after reload has no transparent color at corner 1.");
        // Test loading an image whose transparent color index is out of range.
        // This image was generated by taking an initial image with a palette size
        // of 6 colors, and setting the transparent color index to 6 (one higher
        // than the largest allowed index), as follows:
        // @code
        // $image = imagecreatefromgif('core/tests/fixtures/files/image-test.gif');
        // imagecolortransparent($image, 6);
        // imagegif($image, 'core/tests/fixtures/files/image-test-transparent-out-of-range.gif');
        // @endcode
        // This allows us to test that an image with an out-of-range color index
        // can be loaded correctly.
        $file = 'image-test-transparent-out-of-range.gif';
        $image = $this->imageFactory
            ->get('core/tests/fixtures/files/' . $file);
        $this->assertTrue($image->isValid(), "Image '{$file}' after load should be valid, but it is not.");
        $this->assertTrue(imageistruecolor($image->getToolkit()
            ->getResource()), "Image '{$file}' after load should be a truecolor image, but it is not.");
    }
    
    /**
     * Tests calling a missing image operation plugin.
     */
    public function testMissingOperation() : void {
        // Load up a fresh image.
        $image = $this->imageFactory
            ->get('core/tests/fixtures/files/image-test.png');
        $this->assertTrue($image->isValid(), "Image 'image-test.png' after load should be valid, but it is not.");
        // Try perform a missing toolkit operation.
        $this->assertFalse($image->apply('missing_op', []), 'Calling a missing image toolkit operation plugin should fail, but it did not.');
    }

}