tsoid/dist/src/promises/__tests__/bind.test.js

Typed functional library to deal with async operations.

"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
Object.defineProperty(exports, "__esModule", { value: true });
const bind_1 = require("../bind");
const safe_1 = require("../safe");
describe('bind', () => {
    it('Should bind three actions', () => __awaiter(void 0, void 0, void 0, function* () {
        const initial = () => Promise.resolve(1);
        const doubleP = (x) => Promise.resolve(x * 2);
        const tripleP = (x) => Promise.resolve(x * 3);
        const stringfyP = (x) => Promise.resolve(`${x}`);
        const result = yield bind_1.default(initial, doubleP, tripleP, stringfyP);
        expect(result).toBe('6');
    }));
    it('Should propagate failure', () => __awaiter(void 0, void 0, void 0, function* () {
        const initial = () => Promise.resolve(1);
        const doubleP = (x) => Promise.resolve(x * 2);
        const tripleP = () => Promise.reject(new Error('X is invalid!'));
        const stringfyP = (x) => Promise.resolve(`${x}`);
        const result = yield safe_1.default(bind_1.default, initial, doubleP, tripleP, stringfyP);
        expect(result).toBeInstanceOf(Error);
        expect(result.message).toBe('X is invalid!');
    }));
    it('Should implement the associative monad law', () => __awaiter(void 0, void 0, void 0, function* () {
        const m = () => Promise.resolve(1);
        const f = (x) => Promise.resolve(x + 1);
        const g = (x) => Promise.resolve(x / 2);
        const res1 = yield bind_1.default(m, f, g);
        const res2 = yield bind_1.default(m, (x) => bind_1.default(() => x, f, g));
        expect(res1).toBe(res2);
    }));
});