testing

name	testing
description	TDD/BDD testing principles. Use when writing tests, reviewing test coverage, setting up testing, or discussing test strategy and test architecture.
context	fork
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Testing - Principes TDD/BDD (2026)

Principes universels de testing pour toutes les technologies du framework Claude-Craft.

Principes fondamentaux

• TDD Cycle: RED → GREEN → REFACTOR
• Couverture cible: >= 80%
• Pyramide: Unit (70%) > Integration (20%) > E2E (10%)
• Pattern: Arrange-Act-Assert (AAA)
• Nommage: Tests descriptifs expliquant le comportement

Outils recommandés 2026

Stack	Unit/Composants	E2E/Browser	Mutation Testing
JS/TS/React	Vitest 4.1+ (Browser Mode stable)	Playwright	Stryker
PHP/Laravel/Symfony	Pest 4.5+ (PHPUnit 12, Browser Testing)	Playwright via Pest	Infection
Python	pytest 8.x + Ruff 0.8+	Playwright	Mutmut
Flutter	flutter_test + bloc_test 10+	Patrol 3.13+	built-in
React Native	RNTL + Jest	Detox/Maestro	Stryker

Sources : Vitest 4, Pest 4, Stryker Mutator

Stratégies 2026

Vitest 4 — Browser Mode stable

Abandonner JSDOM lourd. Chromium/Firefox/WebKit natifs.

// vitest.config.ts
export default defineConfig({
  test: {
    browser: {
      enabled: true,
      name: 'chromium', // ou 'firefox', 'webkit'
      provider: 'playwright',
    },
  },
});

Source : Vitest Browser Mode

Mutation Testing — "Coverage ment, mutation scores disent la vérité"

Tester la qualité des tests. Mutation score >= 80%.

# Stryker (JS/TS/C#)
npx stryker run

# Infection (PHP)
vendor/bin/infection --min-msi=80

# Mutmut (Python)
mutmut run

Source : Stryker Mutator

Property-based Testing

Générer des tests à partir de propriétés invariantes.

// fast-check (JS/TS)
import fc from 'fast-check';

test('sorting preserves all elements', () => {
  fc.assert(
    fc.property(fc.array(fc.integer()), (arr) => {
      const sorted = [...arr].sort();
      return sorted.length === arr.length;
    })
  );
});

Source : fast-check

Pest 4 — Browser Testing intégré

// Pest 4.5+ avec Playwright natif
test('user can login', function () {
    $this->browse(function (Browser $browser) {
        $browser->visit('/login')
            ->type('email', '[e-mail]')
            ->type('password', 'secret')
            ->press('Login')
            ->assertPathIs('/dashboard');
    });
});

Source : Pest 4 Browser Testing

Vitest Workspaces — Monorepos

// vitest.workspace.ts
export default defineWorkspace([
  'packages/*/vitest.config.ts', // Unit tests
  {
    test: {
      browser: { enabled: true, name: 'chromium' },
      include: ['e2e/**/*.test.ts'],
    },
  }, // Browser tests
]);

Source : Vitest Workspaces

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Voir @.claude/references/base/testing.md pour documentation complète.