updux/src/buildMiddleware/test.js

import { test } from 'tap';
import sinon from 'sinon';

import { buildMiddleware } from './index.js';
import { action } from '../actions.js';

test('single effect', async (t) => {
    const effect = (api) => (next) => (action) => {
        t.same(action, { type: 'foo' });
        t.has(api, {
            actions: {},
            selectors: {},
        });
        next();
    };

    const middleware = buildMiddleware([effect]);

    await new Promise((resolve) => {
        middleware({})(resolve)({ type: 'foo' });
    });
});

test('augmented api', async (t) => {
    const effect = (api) => (next) => async (action) => {
        await t.test('selectors', async (t) => {
            t.same(api.getState.getB(), 1);
            t.same(api.selectors.getB({ a: { b: 2 } }), 2);

            t.same(api.getState(), { a: { b: 1 } });
        });

        await t.test('dispatch', async (t) => {
            t.same(api.actions.actionOne(), { type: 'actionOne' });
            api.dispatch.actionOne('the payload');
        });

        next();
    };

    const middleware = buildMiddleware(
        [effect],
        {
            actionOne: action('actionOne'),
        },
        {
            getB: (state) => state.a.b,
        }
    );

    const getState = sinon.fake.returns({ a: { b: 1 } });
    const dispatch = sinon.fake.returns();

    await new Promise((resolve) => {
        middleware({
            getState,
            dispatch,
        })(resolve)({ type: 'foo' });
    });

    t.ok(dispatch.calledOnce);

    t.ok(dispatch.calledWith({ type: 'actionOne', payload: 'the payload' }));
});

test('subduxes', async (t) => {
    const effect1 = (api) => (next) => (action) => {
        next({
            type: action.type,
            payload: [...action.payload, 1],
        });
    };
    const effect2 = (api) => (next) => (action) => {
        next({
            type: action.type,
            payload: [...action.payload, 2],
        });
    };
    const effect3 = (api) => (next) => (action) => {
        next({
            type: action.type,
            payload: [...action.payload, 3],
        });
    };

    const mw = buildMiddleware(
        [effect1],
        {},
        {},
        {
            a: { middleware: effect2 },
            b: { middleware: effect3 },
        }
    );

    mw({})(({ payload }) => {
        t.same(payload, [1, 2, 3]);
    })({ type: 'foo', payload: [] });

    t.test('api for subduxes', async (t) => {
        const effect = (api) => (next) => (action) => {
            t.same(api.getState(), 3);
            next();
        };

        const mwInner = buildMiddleware([effect]);
        const mwOuter = buildMiddleware(
            [],
            {},
            {},
            { alpha: { middleware: mwInner } }
        );

        await new Promise((resolve) => {
            mwOuter({
                getState: () => ({ alpha: 3 }),
            })(resolve)({ type: 'foo' });
        });
    });
});