Add ability to set afterLoad static methods on Controllers

[lb-]

• When a controller is registered, the afterLoad static method, if present, will be called
• It gets passed the application instance and the identifier that was used to register it
• implements Feature request - Controller registration (load) callback  #574

Note: Hopefully I have added things correctly, I could not get the examples working so have only added unit tests.

[rik]

afterLoad makes me think this will be called after the load event. afterRegister seems less confusing to me.

[lb-]

afterLoad makes me think this will be called after the load event. afterRegister seems less confusing to me.

Yeah - see #574 (comment)

Basically, the current static method shouldLoad is already in place.

While afterRegister better aligns with the overall nomenclature of register but then there will be two static methods; shouldLoad and afterRegister that will be inconsistent.

A good thing to note is that you can also load a suite of controllers via application.load([...someControllersWithIdentifiers]) - I think that is why the naming is inconsistent.

application.register only takes one controller (and calls application.load under the hood), application.load takes one or more controllers.

If we opt for afteRegister, I think we should also move to shouldRegister with handling for a legacy fallback of shouldLoad (although, this is a bit tricky due to the boolean check and the fact it is a static get method, so checking for its presence needs to be done carefully).

[marcoroth]

afterLoad makes me think this will be called after the load event. afterRegister seems less confusing to me.

What if we call it afterApplicationLoad()?

But yeah, agreed. The naming is not ideal. I wonder if it's worth to go through a deprecation cycle to align it to register.

[lb-]

I think afterApplicationLoad could be confusing in a different way. It may be inferred to be after the application has loaded instead of after this controller is loaded by the application.

What if I Update to afterRegister or afterRegistered ?

Then can explore a rename if shouldLoad to should register as a seperate issue.

[marcoroth]

Looking at this function I can totally understand why it's called shouldLoad, it's just super confusing because you usually don't call load() in your application

stimulus/src/core/application.ts

Lines 56 to 65 in da425c4

	load(...definitions: Definition[]): void
	load(definitions: Definition[]): void
	load(head: Definition | Definition[], ...rest: Definition[]) {
	const definitions = Array.isArray(head) ? head : [head, ...rest]
	definitions.forEach(definition => {
	if ((definition.controllerConstructor as any).shouldLoad) {
	this.router.loadDefinition(definition)
	}
	})
	}

[lb-]

The documentation does reference application.load when used with the webpack helpers.

https://stimulus.hotwired.dev/handbook/installing#using-webpack-helpers

[lb-]

Note to self - rebase on master now that eslint/prettier is adopted.

[dhh]

Went with shouldLoad because it's called as part of load. Even though the user invocation happens through register. I think @lb- is right to keep this consistent. Also don't think there's enough value in a rename to proceed with a depreciation cycle here to be honest.

[lb-]

Thanks @dhh & @marcoroth