--- /dev/null
+<?php
+
+namespace Drupal\Tests\Component\Utility;
+
+use Drupal\Component\Utility\Image;
+use Drupal\Tests\UnitTestCase;
+
+/**
+ * @coversDefaultClass \Drupal\Component\Utility\Image
+ * @group Image
+ */
+class ImageTest extends UnitTestCase {
+
+ /**
+ * Tests all control flow branches in image_dimensions_scale().
+ *
+ * @dataProvider providerTestScaleDimensions
+ */
+ public function testScaleDimensions($input, $output) {
+ // Process the test dataset.
+ $return_value = Image::scaleDimensions($input['dimensions'], $input['width'], $input['height'], $input['upscale']);
+
+ // Check the width.
+ $this->assertEquals($output['dimensions']['width'], $input['dimensions']['width'], sprintf('Computed width (%s) does not equal expected width (%s)', $output['dimensions']['width'], $input['dimensions']['width']));
+
+ // Check the height.
+ $this->assertEquals($output['dimensions']['height'], $input['dimensions']['height'], sprintf('Computed height (%s) does not equal expected height (%s)', $output['dimensions']['height'], $input['dimensions']['height']));
+
+ // Check the return value.
+ $this->assertEquals($output['return_value'], $return_value, 'Incorrect return value.');
+ }
+
+ /**
+ * Provides data for image dimension scale tests.
+ *
+ * @return array
+ * Keyed array containing:
+ * - 'input' - Array which contains input for Image::scaleDimensions().
+ * - 'output' - Array which contains expected output after passing
+ * through Image::scaleDimensions. Also contains a boolean
+ * 'return_value' which should match the expected return value.
+ *
+ * @see testScaleDimensions()
+ */
+ public function providerTestScaleDimensions() {
+ // Define input / output datasets to test different branch conditions.
+ $tests = [];
+
+ // Test branch conditions:
+ // - No height.
+ // - Upscale, don't need to upscale.
+ $tests[] = [
+ 'input' => [
+ 'dimensions' => [
+ 'width' => 1000,
+ 'height' => 2000,
+ ],
+ 'width' => 200,
+ 'height' => NULL,
+ 'upscale' => TRUE,
+ ],
+ 'output' => [
+ 'dimensions' => [
+ 'width' => 200,
+ 'height' => 400,
+ ],
+ 'return_value' => TRUE,
+ ],
+ ];
+
+ // Test branch conditions:
+ // - No width.
+ // - Don't upscale, don't need to upscale.
+ $tests[] = [
+ 'input' => [
+ 'dimensions' => [
+ 'width' => 1000,
+ 'height' => 800,
+ ],
+ 'width' => NULL,
+ 'height' => 140,
+ 'upscale' => FALSE,
+ ],
+ 'output' => [
+ 'dimensions' => [
+ 'width' => 175,
+ 'height' => 140,
+ ],
+ 'return_value' => TRUE,
+ ],
+ ];
+
+ // Test branch conditions:
+ // - Source aspect ratio greater than target.
+ // - Upscale, need to upscale.
+ $tests[] = [
+ 'input' => [
+ 'dimensions' => [
+ 'width' => 8,
+ 'height' => 20,
+ ],
+ 'width' => 200,
+ 'height' => 140,
+ 'upscale' => TRUE,
+ ],
+ 'output' => [
+ 'dimensions' => [
+ 'width' => 56,
+ 'height' => 140,
+ ],
+ 'return_value' => TRUE,
+ ],
+ ];
+
+ // Test branch condition: target aspect ratio greater than source.
+ $tests[] = [
+ 'input' => [
+ 'dimensions' => [
+ 'width' => 2000,
+ 'height' => 800,
+ ],
+ 'width' => 200,
+ 'height' => 140,
+ 'upscale' => FALSE,
+ ],
+ 'output' => [
+ 'dimensions' => [
+ 'width' => 200,
+ 'height' => 80,
+ ],
+ 'return_value' => TRUE,
+ ],
+ ];
+
+ // Test branch condition: don't upscale, need to upscale.
+ $tests[] = [
+ 'input' => [
+ 'dimensions' => [
+ 'width' => 100,
+ 'height' => 50,
+ ],
+ 'width' => 200,
+ 'height' => 140,
+ 'upscale' => FALSE,
+ ],
+ 'output' => [
+ 'dimensions' => [
+ 'width' => 100,
+ 'height' => 50,
+ ],
+ 'return_value' => FALSE,
+ ],
+ ];
+
+ return $tests;
+ }
+
+}