Add missing tests for lazy-load script/style functions

plugins/image-prioritizer/tests/test-helper.php

@@ -222,4 +222,31 @@ public function test_auto_sizes( array $element_metrics, string $buffer, string
 			"Buffer snapshot:\n$buffer"
 		);
 	}
+
+	/**
+	 * Test image_prioritizer_get_video_lazy_load_script.
+	 *
+	 * @covers ::image_prioritizer_get_video_lazy_load_script
+	 */
+	public function test_image_prioritizer_get_video_lazy_load_script(): void {
+		$this->assertGreaterThan( 0, strlen( image_prioritizer_get_video_lazy_load_script() ) );
+	}
+
+	/**
+	 * Test image_prioritizer_get_lazy_load_bg_image_script.
+	 *
+	 * @covers ::image_prioritizer_get_lazy_load_bg_image_script
+	 */
+	public function test_image_prioritizer_get_lazy_load_bg_image_script(): void {
+		$this->assertGreaterThan( 0, strlen( image_prioritizer_get_lazy_load_bg_image_script() ) );
+	}
+
+	/**
+	 * Test image_prioritizer_get_lazy_load_bg_image_stylesheet.
+	 *
+	 * @covers ::image_prioritizer_get_lazy_load_bg_image_stylesheet
+	 */
+	public function test_image_prioritizer_get_lazy_load_bg_image_stylesheet(): void {
+		$this->assertGreaterThan( 0, strlen( image_prioritizer_get_lazy_load_bg_image_stylesheet() ) );
+	}
 }