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[TypeScript] typegen creating output which conflicts with @typescript-eslint/ban-types
Description
Typegen output is offending @typescript-eslint/ban-types whose mission statement is
Some builtin types have aliases, some types are considered dangerous or harmful. It's often a good idea to ban certain types to help with consistency and safety.
-- README
Expected Result
Typegen output should not use incorrect types which are flagged by the @typescript-eslint/ban-types rule
Actual Result
The specific error is:
Don't use `{}` as a type. `{}` actually means "any non-nullish value".
- If you want a type meaning "any object", you probably want `Record<string, unknown>` instead.
- If you want a type meaning "any value", you probably want `unknown` instead.
- If you want a type meaning "empty object", you probably want `Record<string, never>` instead.e
And can occur on invokeSrcNameMap, eventsCausingServices, eventsCausingGuards, and eventsCausingDelays:

Reproduction
Typegen doesn't run on codesandbox, but the following machine will trigger the above error on [email protected]:
import { createModel } from 'xstate/lib/model';
export const testModel = createModel(
{
name: null as null | string,
},
{
events: {
setName: (name: string) => ({
name,
}),
reset: () => ({}),
},
},
);
export const surveyFormMachine = testModel.createMachine({
tsTypes: {},
id: 'test',
initial: 'idle',
context: testModel.initialContext,
states: {
idle: {},
},
on: {
reset: {
actions: 'resetContext',
},
setName: {
actions: 'setName',
},
},
});
Additional context
XState 4.29.0 statelyai.stately-vscode 1.5.6
I'm currently working around this with an override in my eslint.json to disable that rule for *.typegen.ts
@mattpocock we can probably just output never at those locations instead of {} - but it's best to double-check that and add those to all existing type gen tests in this repo. Maybe we could even just skip those keys if they are empty~? That could be even better as we'd save some parsing time.
Yes, although applying any linting whatsoever to generated files is probably not a great idea. When we release the CLI, we'll even be able to gitignore these assets and generate them on CI.
This is a cheap enough change to make, though.
When we release the CLI, we'll even be able to gitignore these assets and generate them on CI.
@mattpocock Is there any example on how to do this on GH Actions? thanks in advance!
@horacioh Yes, see the CLI docs:
https://xstate.js.org/docs/packages/xstate-cli/#xstate-cli
YES!! I saw it and forgot to mention it here ;)