Claude Desktop Commander MCP

/** * Unit tests for A/B test feature flag system * Tests that missing/empty experiments config doesn't break anything */ import assert from 'assert'; // Mock the dependencies before importing ab-test let mockExperiments = {}; let mockConfigValues = {}; // Mock featureFlagManager const mockFeatureFlagManager = { get: (key, defaultValue) => { if (key === 'experiments') return mockExperiments; return defaultValue; } }; // Mock configManager const mockConfigManager = { getValue: async (key) => mockConfigValues[key], setValue: async (key, value) => { mockConfigValues[key] = value; } }; // We need to test the logic directly since we can't easily mock ES modules // Recreate the core functions with injected dependencies function getExperiments() { return mockFeatureFlagManager.get('experiments', {}); } function hashCode(str) { let hash = 0; for (let i = 0; i < str.length; i++) { hash = ((hash << 5) - hash) + str.charCodeAt(i); hash |= 0; } return Math.abs(hash); } const variantCache = {}; async function getVariant(experimentName) { const experiments = getExperiments(); const experiment = experiments[experimentName]; if (!experiment?.variants?.length) return null; if (variantCache[experimentName]) { return variantCache[experimentName]; } const configKey = `abTest_${experimentName}`; const existing = await mockConfigManager.getValue(configKey); if (existing && experiment.variants.includes(existing)) { variantCache[experimentName] = existing; return existing; } const clientId = await mockConfigManager.getValue('clientId') || ''; const hash = hashCode(clientId + experimentName); const variantIndex = hash % experiment.variants.length; const variant = experiment.variants[variantIndex]; await mockConfigManager.setValue(configKey, variant); variantCache[experimentName] = variant; return variant; } async function hasFeature(featureName) { const experiments = getExperiments(); if (!experiments || typeof experiments !== 'object') return false; for (const [expName, experiment] of Object.entries(experiments)) { if (experiment?.variants?.includes(featureName)) { const variant = await getVariant(expName); return variant === featureName; } } return false; } // Clear state between tests function resetState() { mockExperiments = {}; mockConfigValues = {}; Object.keys(variantCache).forEach(k => delete variantCache[k]); } // Test runner async function runTests() { let passed = 0; let failed = 0; const test = async (name, fn) => { resetState(); try { await fn(); console.log(`✅ ${name}`); passed++; } catch (e) { console.log(`❌ ${name}`); console.log(` Error: ${e.message}`); failed++; } }; console.log('\n🧪 A/B Test Feature Flag Tests\n'); // Test 1: No experiments at all await test('hasFeature returns false when no experiments exist', async () => { mockExperiments = {}; const result = await hasFeature('showOnboardingPage'); assert.strictEqual(result, false); }); // Test 2: Experiments is undefined/null await test('hasFeature returns false when experiments is undefined', async () => { mockExperiments = undefined; const result = await hasFeature('showOnboardingPage'); assert.strictEqual(result, false); }); // Test 3: Empty experiments object await test('hasFeature returns false with empty experiments object', async () => { mockExperiments = {}; const result = await hasFeature('anyFeature'); assert.strictEqual(result, false); }); // Test 4: Experiment exists but variants array is empty await test('hasFeature returns false when experiment has empty variants', async () => { mockExperiments = { 'TestExp': { variants: [] } }; const result = await hasFeature('showOnboardingPage'); assert.strictEqual(result, false); }); // Test 5: Experiment exists but variants is undefined await test('hasFeature returns false when variants is undefined', async () => { mockExperiments = { 'TestExp': {} }; const result = await hasFeature('showOnboardingPage'); assert.strictEqual(result, false); }); // Test 6: Feature not in any experiment await test('hasFeature returns false for unknown feature', async () => { mockExperiments = { 'OnboardingPreTool': { variants: ['noOnboardingPage', 'showOnboardingPage'] } }; const result = await hasFeature('unknownFeature'); assert.strictEqual(result, false); }); // Test 7: Feature exists, user assigned to it await test('hasFeature returns true when user is assigned to that variant', async () => { mockExperiments = { 'OnboardingPreTool': { variants: ['noOnboardingPage', 'showOnboardingPage'] } }; mockConfigValues = { 'abTest_OnboardingPreTool': 'showOnboardingPage' }; const result = await hasFeature('showOnboardingPage'); assert.strictEqual(result, true); }); // Test 8: Feature exists, user assigned to different variant await test('hasFeature returns false when user is assigned to different variant', async () => { mockExperiments = { 'OnboardingPreTool': { variants: ['noOnboardingPage', 'showOnboardingPage'] } }; mockConfigValues = { 'abTest_OnboardingPreTool': 'noOnboardingPage' }; const result = await hasFeature('showOnboardingPage'); assert.strictEqual(result, false); }); // Test 9: New user gets deterministic assignment await test('new user gets deterministic variant assignment based on clientId', async () => { mockExperiments = { 'OnboardingPreTool': { variants: ['noOnboardingPage', 'showOnboardingPage'] } }; mockConfigValues = { clientId: 'test-client-123' }; const result1 = await hasFeature('showOnboardingPage'); const result2 = await hasFeature('noOnboardingPage'); // One must be true, one must be false assert.strictEqual(result1 !== result2, true, 'User should be in exactly one variant'); // Check it was persisted const persisted = mockConfigValues['abTest_OnboardingPreTool']; assert.ok(persisted, 'Assignment should be persisted to config'); assert.ok(['noOnboardingPage', 'showOnboardingPage'].includes(persisted)); }); // Test 10: Malformed experiment data doesn't crash await test('malformed experiment data does not throw', async () => { mockExperiments = { 'BadExp1': null, 'BadExp2': 'not an object', 'BadExp3': { variants: 'not an array' }, 'GoodExp': { variants: ['a', 'b'] } }; // Should not throw const result = await hasFeature('a'); // Result depends on assignment, but shouldn't crash assert.ok(typeof result === 'boolean'); }); // Summary console.log(`\n📊 Results: ${passed} passed, ${failed} failed\n`); return failed === 0; } // Run tests runTests().then(success => { process.exit(success ? 0 : 1); }).catch(err => { console.error('Test runner error:', err); process.exit(1); });