Incomplete type definitions for BasePlugin

[genu]

Initial checklist

• I understand this is a bug report and questions should be posted in the Community Forum
• I searched issues and couldn’t find anything (or linked relevant results below)

Link to runnable example

No response

Steps to reproduce

According to the BasePlugin Class, I should be able to pass 3 types:

uppy/packages/@uppy/core/src/BasePlugin.ts

Lines 42 to 47 in 57b5909

	export default class BasePlugin<
	Opts extends PluginOpts,
	M extends Meta,
	B extends Body,
	PluginState extends Record<string, unknown> = Record<string, unknown>,
	> {

The type definitions, however, only allow passing in the plugin options as a type:

uppy/packages/@uppy/core/types/index.d.ts

Lines 79 to 83 in 57b5909

	export class BasePlugin<TOptions extends PluginOptions = DefaultPluginOptions> {
	id: string
	// eslint-disable-next-line no-use-before-define
	uppy: Uppy

Any reason why the type is more restrictive?

Expected behavior

I should be able to create a plugin specifying the meta and body like this:

class MyPlugin extends BasePlugin<MyPluginOptions, CustomMeta, CustomBody> {
   super(uppy, opts);

}

Actual behavior

The Base plugin only allows plugin options, which means that I'm unable strong type the meta and body inside the plugin.

Only this is allowed:

class MyPlugin extends BasePlugin<MyPluginOptions> {
    super(uppy, opts);
             ^--- is Just an Uppy type rather than a `Uppy<CustomMeta, CustomBody>`
}

[Murderlon]

In order to do a TS migration without constantly introducing new breaking type changes as we move through the codebase, we write the source in TS but do not emit type files from it. Soon we are releasing major versions for all plugins at once so the types work together. In the meantime you have to use outdated types.