yumechi-no-kuni/test/prelude/maybe.ts
Aya Morisawa e9955e01d6
Introduce option type (#4150)
* Introduce option type

* Improve test naming
2019-02-06 13:42:35 +09:00

28 lines
626 B
TypeScript

/*
* Tests of Maybe
*
* How to run the tests:
* > mocha test/prelude/maybe.ts --require ts-node/register
*
* To specify test:
* > mocha test/prelude/maybe.ts --require ts-node/register -g 'test name'
*/
import * as assert from 'assert';
import { just, nothing } from '../../src/prelude/maybe';
describe('just', () => {
it('has a value', () => {
assert.deepStrictEqual(just(3).isJust(), true);
});
it('has the inverse called get', () => {
assert.deepStrictEqual(just(3).get(), 3);
});
});
describe('nothing', () => {
it('has no value', () => {
assert.deepStrictEqual(nothing().isJust(), false);
});
});