updux/src/mutations.test.ts

import { createAction } from '@reduxjs/toolkit';
import { test, expect } from 'vitest';
import Updux from './Updux.js';

test('set a mutation', () => {
    const dux = new Updux({
        initialState: 'potato',
        actions: {
            foo: (x: string) => ({ x }),
            bar: null,
        },
    });

    let didIt = false;

    dux.addMutation(dux.actions.foo, (payload, action) => () => {
        expectTypeOf(payload).toMatchTypeOf<{ x: string }>();

        didIt = true;
        expect(payload).toEqual({ x: 'hello ' });
        expect(action).toEqual(dux.actions.foo('hello '));
        return payload.x + action.type;
    });

    const result = dux.reducer(undefined, dux.actions.foo('hello '));
    expect(didIt).toBeTruthy();
    expect(result).toEqual('hello foo');
});

test('catch-all mutation', () => {
    const dux = new Updux({
        initialState: '',
    });

    dux.addMutation(
        () => true,
        (payload, action) => () => 'got it',
    );

    expect(dux.reducer(undefined, { type: 'foo' })).toEqual('got it');
});

test('default mutation', () => {
    const dux = new Updux({
        initialState: '',
        actions: {
            foo: null,
        },
    });

    dux.addMutation(dux.actions.foo, () => () => 'got it');

    dux.setDefaultMutation((_payload, action) => () => action.type);

    expect(dux.reducer(undefined, { type: 'foo' })).toEqual('got it');
    expect(dux.reducer(undefined, { type: 'bar' })).toEqual('bar');
});

test('mutation of a subdux', () => {
    const baz = createAction('baz');
    const noop = createAction('noop');
    const stopit = createAction('stopit');

    const bar = new Updux({
        initialState: 0,
        actions: {
            baz,
            stopit,
        },
    });
    bar.addMutation(baz, () => () => 1);
    bar.addMutation(stopit, () => () => 2);

    const foo = new Updux({
        subduxes: { bar },
    });
    foo.addMutation(stopit, () => (state) => state, true);

    expect(foo.reducer(undefined, noop())).toHaveProperty('bar', 0);
    expect(foo.reducer(undefined, baz())).toHaveProperty('bar', 1);
    expect(foo.reducer(undefined, stopit())).toHaveProperty('bar', 0);
});

test('actionType as string', () => {
    const dux = new Updux({
        actions: {
            doIt: (id: number) => id,
        },
    });

    dux.addMutation('doIt', (payload) => (state) => {
        expectTypeOf(payload).toMatchTypeOf<number>();
        return state;
    });

    expect(() => {
        // @ts-ignore
        dux.addMutation('unknown', () => (x) => x);
    }).toThrow();
});