lib/services/render-loop.spec.ts

0001 import { runIsolated, shouldRenderFrame } from './render-loop';
0002
0003 describe('shouldRenderFrame', () => {
0004   const clean = [{ dirty: false }, { dirty: false }];
0005
0006   it('stays idle on demand when nothing is dirty', () => {
0007     expect(shouldRenderFrame(false, false, clean)).toBe(false);
0008     expect(shouldRenderFrame(false, false, [])).toBe(false);
0009   });
0010
0011   it('renders on demand after invalidate() or when any one view is dirty', () => {
0012     expect(shouldRenderFrame(false, true, clean)).toBe(true);
0013     expect(shouldRenderFrame(false, false, [{ dirty: false }, { dirty: true }])).toBe(true);
0014   });
0015
0016   it('renders every frame in continuous mode', () => {
0017     expect(shouldRenderFrame(true, false, clean)).toBe(true);
0018   });
0019 });
0020
0021 describe('runIsolated', () => {
0022   it('keeps calling the remaining targets after one throws, and reports the offenders', () => {
0023     const called: string[] = [];
0024     const errors: string[] = [];
0025     const failed = runIsolated(['a', 'bad', 'c', 'worse'],
0026       target => {
0027         called.push(target);
0028         if (target === 'bad' || target === 'worse') throw new Error(target);
0029       },
0030       (target, error) => errors.push(`${target}:${(error as Error).message}`));
0031
0032     expect(called).toEqual(['a', 'bad', 'c', 'worse']);
0033     expect(failed).toEqual(['bad', 'worse']);
0034     expect(errors).toEqual(['bad:bad', 'worse:worse']);
0035   });
0036
0037   it('returns no offenders when every target succeeds', () => {
0038     expect(runIsolated([1, 2, 3], () => undefined, () => { throw new Error('unreachable'); })).toEqual([]);
0039   });
0040 });