JS errors if Tag Manager is disabled via googlesitekit_available_modules

Bug Description

Similar to #5072, but for covering the case that the Tag Manager module is not available (e.g. via googlesitekit_available_modules filter): There will be JS errors at least in the Analytics setup as it unconditionally calls modules/tagmanager selectors.

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Acceptance criteria

• Any references to modules/tagmanager store selectors or actions from a component or store that is part of another module should only occur after verifying that the module is available (available, regardless of whether it is active or not).
  • In other words, this issue should cover all accesses within assets/js/modules/* other than assets/js/modules/tagmanager.
  • A good way to tackle this is to search for any MODULES_TAGMANAGER references in those other module directories and adjust/wrap them accordingly.
  • At a minimum, the check needs to ensure that the respective MODULES_TAGMANAGER datastore is available before calling a selector or action on it.

Implementation Brief

• Find all instances of select( MODULES_TAGMANAGER )/dispatch( MODULES_TAGMANAGER ) and ensure that isModuleAvailable( MODULES_TAGMANAGER ) is true before using those selectors/dispatching those actions.
• Find instances of isModuleActive( MODULES_TAGMANAGER ) and check for isModuleAvailable( MODULES_TAGMANAGER ).

Note: any code in any module should be checked, not just Tag Manager specific code. Be sure to look for Tag Manager selectors/action dispatches across the whole plugin when making these changes.

Test Coverage

• Add tests to any components with existing tests that disable Tag Manager; ensure they still render without errors/console warnings.

QA Brief

• Add the filter below to your WordPress site, e.g. in your theme’s functions.php.
• Set up the Analytics module and ensure there are no errors due to Tag Manager not being available.

Filter

add_filter(
	'googlesitekit_available_modules',
	function( $modules ) {
		$index = array_search( 'tagmanager', $modules, true );
		if ( false !== $index ) {
			unset( $modules[ $index ] );
			return array_values( $modules );
		}
		return $modules;
	}
);

Changelog entry

• Fix bug that caused errors to appear in Analytics module when Tag Manager module is not available.

[tofumatt]

@hussain-t I see this was assigned a month ago before the IB/approach in #5071 was finalised. Since I wrote up that IB I’m going to handle this and #5072, because there’s a lot of overlap 🙂

[mohitwp]

QA Update ✅

• Verified on both latest and dev environment using QAB.
• On latest environment I’m able to reproduce issue.
• On dev environment errors are not showing if Tag Manager module is not available.

https://user-images.githubusercontent.com/94359491/199218497-59bdd92f-7bef-4b13-9c96-0e87a969d4f2.mp4