Add test cases for mobile alternate link wp_head hook

Author: thelovekesh

tests/php/src/MobileRedirectionTest.php

@@ -168,6 +168,23 @@ public function test_maybe_add_mobile_switcher_hooks() {
 		$this->assertSame( 10, has_action( 'amp_post_template_footer', [ $this->instance, 'add_mobile_version_switcher_link' ] ) );
 	}
 
+	/**
+	 * @covers ::add_mobile_alternative_link_head_hook()
+	 */
+	public function test_add_mobile_alternative_link_head_hook() {
+		AMP_Options_Manager::update_option( Option::THEME_SUPPORT, AMP_Theme_Support::STANDARD_MODE_SLUG );
+		$this->go_to( '/' );
+		$this->instance->add_mobile_alternative_link_head_hook();
+		$this->assertTrue( amp_is_request() );
+		$this->assertFalse( has_action( 'wp_head', [ $this->instance, 'add_mobile_alternative_link' ] ) );
+
+		AMP_Options_Manager::update_option( Option::THEME_SUPPORT, AMP_Theme_Support::TRANSITIONAL_MODE_SLUG );
+		$this->go_to( '/' );
+		$this->instance->add_mobile_alternative_link_head_hook();
+		$this->assertFalse( amp_is_request() );
+		$this->assertSame( 10, has_action( 'wp_head', [ $this->instance, 'add_mobile_alternative_link' ] ) );
+	}
+
 	/**
 	 * Get data for test_mobile_alternate_link_hook
 	 *