JS Testing Lessons

Jasmine Foundations Jasmine gives JavaScript teams a descriptive spec style for unit. Where it fits Readable unit tests around functions and services Spec-style behavior descriptions Spy-based verification of collaborator calls Typical starting point

const spec = { suite:'calculator', case:'adds two numbers', expectation:'result === 4' };
console.log(spec);

Working Productively with Jasmine The practical skill is naming specs well, isolating behavior cleanly, and using spies without turning tests into implementation snapshots. Patterns to practice Keep each spec focused on one outcome Spy on boundaries

const spy = { called:0 };
function save(){ spy.called += 1; }
save();
console.log('spy called', spy.called, 'time(s)');

Production Jasmine Advanced Jasmine work is about suite readability, refactor confidence, and resisting brittle over-mocking. Production checklist Organize suites by behavior area Watch for over-mocking and hidden coupling Keep test names meaningful

const review = { keep:['clear names','small scope'], avoid:['brittle mocks','opaque helpers'] };
console.log(review);

Mocha Foundations Mocha is a flexible JavaScript test runner that became popular. Where it fits Node unit and integration tests Async testing around promises and callbacks Custom test stacks with chosen reporters and assertion tools Typical starting

const suite = ['describe service', 'it handles success', 'it handles failure'];
suite.forEach(step => console.log(step));

Working Productively with Mocha The real leverage in Mocha comes from building a coherent test harness around async behavior, fixtures, and clear suite boundaries. Patterns to practice Test async flows with explicit completion boundaries Keep fixture

const asyncCases = [{ name:'promise resolves', timeoutMs:200 }, { name:'promise rejects', timeoutMs:200 }];
console.log(asyncCases);

Production Mocha Production Mocha use means maintaining test speed, keeping async leaks out, and ensuring contributors can navigate the stack confidently. Production checklist Watch for hanging timers and state bleed Keep CI feedback fast with target

const runner = { reporter:'spec', focus:['integration','service-boundaries'], ci:['fast-feedback','stable-fixtures'] };
console.log(runner);

QUnit Foundations QUnit is a straightforward unit testing framework that stays useful. Where it fits Utility and browser-oriented unit tests Simple module-based organization Fixture-driven DOM testing with low ceremony Typical starting points Group r

const modulePlan = { module:'formatting helpers', assertions:['handles empty input','formats currency'] };
console.log(modulePlan);

Working Productively with QUnit The value of QUnit grows when teams standardize modules, fixtures, and helper usage so tests stay small and transparent. Patterns to practice Use focused modules for related behavior Keep DOM fixture cleanup explicit M

const fixtureLifecycle = ['setup fixture', 'run DOM test', 'cleanup fixture'];
fixtureLifecycle.forEach(step => console.log(step));

Production QUnit Advanced QUnit practice is about discipline: stable fixtures, transparent helpers, and tests that communicate intent without framework noise. Production checklist Review fixture leaks and state bleed Keep helpers tiny and visible Use

const review = { keep:['small modules','clear messages'], avoid:['state leaks','opaque helper magic'] };
console.log(review);

Cypress (automation) Foundations Cypress gives frontend teams fast feedback for end-to-end workflows with. Where it fits Sign-in, checkout, and permission flows Network stubbing and deterministic test data UI debugging with browser-level visibility T

const flow = ['visit /login', 'type email', 'submit form', 'assert dashboard'];
flow.forEach(step => console.log(step));

Working Productively with Cypress (automation) Intermediate Cypress work is about selector discipline, fixture design, and balancing realism with the stability needed in CI. Patterns to practice Prefer data-test or semantic selectors Separate smoke a

const selectors = { email:'[data-test=email]', submit:'[data-test=submit]', alert:'[data-test=alert]' };
console.log(selectors);

Production Cypress (automation) Advanced Cypress strategy includes flaky-test defense, suite partitioning, environment management, and artifact-driven debugging. Production checklist Capture screenshots and videos for CI failures Control runtime by s

const suitePlan = { smoke:['login','checkout'], regression:['filters','permissions'], ci:['screenshots','videos','artifacts'] };
console.log(suitePlan);

Playwright (automation) Foundations Playwright helps teams automate Chromium, Firefox, and WebKit with modern. Where it fits Cross-browser critical-path coverage Reusable auth and fixture setup Trace-based debugging for complex failures Typical start

const browsers = ['chromium', 'firefox', 'webkit'];
console.log('target browsers', browsers);

Working Productively with Playwright (automation) The real leverage comes from fixtures, trace analysis, environment setup, and treating automation as part of release confidence rather than an isolated script collection. Patterns to practice Use fixt

const fixtureModel = { authState:'storageState.json', trace:'retain-on-failure', selectorRule:'prefer role or data-test' };
console.log(fixtureModel);

Production Playwright (automation) Advanced Playwright work means thinking about concurrency, artifact analysis, and how automation fits into delivery strategy. Production checklist Collect traces, screenshots, and videos on failure Balance paralleli

const automation = { parallel:true, artifacts:['trace','screenshot','video'], coverage:['critical paths','cross-browser smoke'] };
console.log(automation);