import { expect } from 'chai'; import u from '../lib'; describe('u.if', () => { it('does not update if the predicate is false', () => { const object = { a: 0 }; let result = u.if(false, { b: 1 }, object); expect(result).to.eql(object); result = u({ x: u.if(false, 1)}, {}); expect(result).to.eql({}); }); it('does update if the predicate is true', () => { const object = { a: 0 }; const result = u.if(true, { b: 1 }, object); expect(result).to.eql({ a: 0, b: 1 }); }); it('will use the result of a function passed as a predicate', () => { const object = { a: 0 }; const aIsThree = x => x.a === 3; const result = u.if(aIsThree, { b: 1 }, object); expect(result).to.eql({ a: 0 }); }); it('can be partially applied', () => { const object = { a: 2 }; const isEven = x => x % 2 === 0; const inc = x => x + 1; const result = u({ a: u.if(isEven, inc), }, object); expect(result).to.eql({ a: 3 }); }); it('freezes the result', () => { expect(Object.isFrozen(u.if(true, {}, {}))).to.be.true; expect(Object.isFrozen(u.if(false, {}, {}))).to.be.true; }); });