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/* eslint-disable @typescript-eslint/ban-ts-comment, @typescript-eslint/no-unused-vars */
import mitt from '..';
interface SomeEventData {
name: string;
}
const emitter = mitt<{
foo: string;
someEvent: SomeEventData;
bar?: number;
}>();
const barHandler = (x?: number) => {};
const fooHandler = (x: string) => {};
const wildcardHandler = (
_type: 'foo' | 'bar' | 'someEvent',
_event: string | SomeEventData | number | undefined
) => {};
/*
* Check that 'on' args are inferred correctly
*/
{
// @ts-expect-error
emitter.on('foo', barHandler);
emitter.on('foo', fooHandler);
emitter.on('bar', barHandler);
// @ts-expect-error
emitter.on('bar', fooHandler);
emitter.on('*', wildcardHandler);
// fooHandler is ok, because ('foo' | 'bar' | 'someEvent') extends string
emitter.on('*', fooHandler);
// @ts-expect-error
emitter.on('*', barHandler);
}
/*
* Check that 'off' args are inferred correctly
*/
{
// @ts-expect-error
emitter.off('foo', barHandler);
emitter.off('foo', fooHandler);
emitter.off('bar', barHandler);
// @ts-expect-error
emitter.off('bar', fooHandler);
emitter.off('*', wildcardHandler);
// fooHandler is ok, because ('foo' | 'bar' | 'someEvent') extends string
emitter.off('*', fooHandler);
// @ts-expect-error
emitter.off('*', barHandler);
}
/*
* Check that 'emit' args are inferred correctly
*/
{
// @ts-expect-error
emitter.emit('someEvent', 'NOT VALID');
emitter.emit('someEvent', { name: 'jack' });
// @ts-expect-error
emitter.emit('foo');
// @ts-expect-error
emitter.emit('foo', 1);
emitter.emit('foo', 'string');
emitter.emit('bar');
emitter.emit('bar', 1);
// @ts-expect-error
emitter.emit('bar', 'string');
}
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