Generating and working "index" interfaces: Is a program transformer what I need?

[AlCalzone]

In my codebase, I have several interfaces that act like an index to a bunch of types:

export interface CCAPIs {
	[Symbol.iterator](): Iterator<CCAPI>;

	// AUTO GENERATION BELOW
	"Alarm Sensor": import("../cc/AlarmSensorCC").AlarmSensorCCAPI;
	Association: import("../cc/AssociationCC").AssociationCCAPI;
	"Association Group Information":
		import("../cc/AssociationGroupInfoCC").AssociationGroupInfoCCAPI;
// ... lots more
}

The build process currently contains 3 steps:

1. compile dependencies of codegen task
2. run codegen task
3. compile projects that depend on generated code

I'd like to eliminate step 2, so I can build the entire project with a single tsc invocation. In addition, when using the CCAPIs interface it should seem like it is the same interface as it is now, without having to list everything in code:

export interface CCAPIs {
	[Symbol.iterator](): Iterator<CCAPI>;
    // The other properties magically appear in IntelliSense and type definitions
}

Is a program transformer what I need? And do I need an additional language server plugin that does the same?

[nonara]

Hello! Sorry for the delay.

It sounds like a Program Transformer could help. A program transformer is essentially middleware for createProgram. You can use this to intercept the tsc process and have it perform any number of steps before returning a Program instance.

One of the main reasons to use one is if you want to generate code that gets automatically added to the Program if it isn't already built. I've done this in many instances. We actually use that for ts-patch itself, also.

Here's an example:

https://github.com/nonara/ts-patch/blob/master/projects/patch/plugin.ts

As for a language service plugin, I don't see a reason why you would need one, but I may not know the full scope of what you're trying to do.

Hope that helps!