Added unit test for cover block render function (#42108)

* Added unit test for cover block render function

* Split testing function into two and addressed feedbacks

* Fixed linting errors

* Resolved issue of unittest failing

phpunit/blocks/render-block-cover-test.php

@@ -0,0 +1,133 @@
+<?php
+/**
+ * Cover block rendering tests.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ */
+
+/**
+ * Tests for the Cover block.
+ *
+ * @group blocks
+ */
+class Tests_Blocks_Render_Cover extends WP_UnitTestCase {
+	/**
+	 * Post object.
+	 *
+	 * @var array
+	 */
+	protected static $post;
+
+	/**
+	 * Attachment id.
+	 *
+	 * @var int
+	 */
+	protected static $attachment_id;
+
+	/**
+	 * Setup method.
+	 */
+	public static function wpSetUpBeforeClass() {
+		self::$post = self::factory()->post->create_and_get();
+		$file       = DIR_TESTDATA . '/images/canola.jpg';
+
+		self::$attachment_id = self::factory()->attachment->create_upload_object(
+			$file,
+			self::$post->ID,
+			array(
+				'post_mime_type' => 'image/jpeg',
+			)
+		);
+
+		set_post_thumbnail( self::$post, self::$attachment_id );
+
+	}
+
+	/**
+	 * Tear down method.
+	 */
+	public static function wpTearDownAfterClass() {
+		wp_delete_post( self::$post->ID, true );
+		wp_delete_post( self::$attachment_id, true );
+	}
+
+	/**
+	 * Test gutenberg_render_block_core_cover() method.
+	 *
+	 * @covers ::gutenberg_render_block_core_cover
+	 */
+	public function test_gutenberg_render_block_core_cover() {
+
+		global $wp_query;
+
+		// Fake being in the loop.
+		$wp_query->in_the_loop = true;
+		$wp_query->post        = self::$post;
+
+		$wp_query->posts = array( self::$post );
+		$GLOBALS['post'] = self::$post;
+
+		$attributes = array(
+			'useFeaturedImage' => true,
+			'backgroundType'   => 'image',
+			'hasParallax'      => true,
+			'isRepeated'       => true,
+			'minHeight'        => '100px',
+		);
+
+		$content  = '<div class="wp-block-cover"><span></span><div class="wp-block-cover__inner-container"></div></div>';
+		$rendered = gutenberg_render_block_core_cover( $attributes, $content );
+
+		$this->assertStringContainsString( wp_get_attachment_image_url( self::$attachment_id, 'full' ), $rendered );
+		$this->assertStringContainsString( 'background-image', $rendered );
+		$this->assertStringContainsString( 'min-height', $rendered );
+
+		// If cover background type is not image.
+		$attributes['backgroundType'] = 'color';
+		$rendered                     = gutenberg_render_block_core_cover( $attributes, '' );
+		$this->assertEmpty( $rendered );
+
+		// If cover background is not post featured image.
+		$attributes['backgroundType']   = 'image';
+		$attributes['useFeaturedImage'] = false;
+		$rendered                       = gutenberg_render_block_core_cover( $attributes, '' );
+		$this->assertEmpty( $rendered );
+	}
+
+	/**
+	 * Test gutenberg_render_block_core_cover() method.
+	 *
+	 * @covers ::gutenberg_render_block_core_cover
+	 */
+	public function test_gutenberg_render_block_core_cover_fixed_or_repeated_background() {
+
+		global $wp_query;
+
+		// Fake being in the loop.
+		$wp_query->post  = self::$post;
+		$GLOBALS['post'] = self::$post;
+
+		$attributes = array(
+			'useFeaturedImage' => true,
+			'backgroundType'   => 'image',
+			'hasParallax'      => false,
+			'isRepeated'       => false,
+			'minHeight'        => '100px',
+			'focalPoint'       => array(
+				'x' => 10,
+				'y' => 10,
+			),
+		);
+
+		$content  = '<div class="wp-block-cover"><span></span><div class="wp-block-cover__inner-container"></div></div>';
+		$rendered = gutenberg_render_block_core_cover( $attributes, $content );
+
+		$this->assertStringContainsString( wp_get_attachment_image_url( self::$attachment_id, 'full' ), $rendered );
+		$this->assertStringContainsString( 'object-position', $rendered );
+		$this->assertStringNotContainsString( 'background-image', $rendered );
+		$this->assertStringNotContainsString( 'min-height', $rendered );
+
+	}
+}