What is Mocha and what are its key features?
Mocha is a feature-rich JavaScript test framework running on Node.js and browser. Key features include: 1) Flexible test structure with describe/it blocks, 2) Support for asynchronous testing, 3) Multiple assertion library support, 4) Test hooks (before, after, etc.), 5) Rich reporting options, 6) Browser support, 7) Plugin architecture.
How do you set up Mocha in a project?
Setup involves: 1) Installing Mocha: npm install --save-dev mocha, 2) Adding test script to package.json: { 'scripts': { 'test': 'mocha' } }, 3) Creating test directory, 4) Choosing assertion library (e.g., Chai), 5) Creating test files with .test.js or .spec.js extension.
What are describe() and it() functions in Mocha?
describe() is used to group related tests (test suite), while it() defines individual test cases. Example: describe('Calculator', () => { it('should add numbers correctly', () => { /* test */ }); }). They help organize tests hierarchically and provide clear test structure.
How does Mocha handle asynchronous tests?
Mocha handles async testing through: 1) done callback parameter, 2) Returning promises, 3) async/await syntax. Example: it('async test', async () => { const result = await asyncOperation(); assert(result); }). Tests wait for async operations to complete.
What are hooks in Mocha and how are they used?
Mocha provides hooks: 1) before() - runs once before all tests, 2) beforeEach() - runs before each test, 3) after() - runs once after all tests, 4) afterEach() - runs after each test. Used for setup and cleanup operations. Example: beforeEach(() => { /* setup */ });
How do you use assertion libraries with Mocha?
Mocha works with various assertion libraries: 1) Node's assert module, 2) Chai for BDD/TDD assertions, 3) Should.js for BDD style, 4) Expect.js for expect() style. Example with Chai: const { expect } = require('chai'); expect(value).to.equal(expected);
What are the different reporting options in Mocha?
Mocha offers various reporters: 1) spec - hierarchical test results, 2) dot - minimal dots output, 3) nyan - fun nyan cat reporter, 4) json - JSON test results, 5) html - HTML test report. Select using --reporter option or configure in mocha.opts.
How do you skip or mark tests as pending in Mocha?
Tests can be skipped/pending using: 1) it.skip() - skip test, 2) describe.skip() - skip suite, 3) it() without callback - mark pending, 4) .only() - run only specific tests. Example: it.skip('test to skip', () => { /* test */ });
What are exclusive tests in Mocha?
Exclusive tests using .only(): 1) it.only() runs only that test, 2) describe.only() runs only that suite, 3) Multiple .only() creates subset of tests to run, 4) Useful for debugging specific tests. Example: it.only('exclusive test', () => { /* test */ });
How do you handle timeouts in Mocha tests?
Timeout handling: 1) Set suite timeout: this.timeout(ms), 2) Set test timeout: it('test', function(done) { this.timeout(ms); }), 3) Default is 2000ms, 4) Set to 0 to disable timeout, 5) Can be set globally or per test.
How do you implement test retries in Mocha?
Test retries configured through: 1) this.retries(n) in test/suite, 2) --retries option in CLI, 3) Retries count for failed tests, 4) Useful for flaky tests, 5) Can be set globally or per test. Example: this.retries(3);
What are Mocha's CLI options?
Common CLI options: 1) --watch for watch mode, 2) --reporter for output format, 3) --timeout for test timeout, 4) --grep for filtering tests, 5) --bail to stop on first failure, 6) --require for requiring modules. Example: mocha --watch --reporter spec
How do you use dynamic test generation?
Dynamic tests created by: 1) Generating it() calls in loops, 2) Using test data arrays, 3) Programmatically creating describe blocks, 4) Using forEach for test cases, 5) Generating tests from data sources.
What is the root hook plugin?
Root hook plugin: 1) Runs hooks for all test files, 2) Configured in mocha.opts or CLI, 3) Used for global setup/teardown, 4) Affects all suites, 5) Useful for shared resources. Example: --require ./root-hooks.js
How do you handle file-level setup in Mocha?
File setup options: 1) Use before/after hooks, 2) Require helper files, 3) Use mocha.opts for configuration, 4) Implement setup modules, 5) Use root hooks plugin. Ensures proper test environment setup.
What are Mocha's configuration options?
Config options include: 1) .mocharc.js/.json file, 2) package.json mocha field, 3) CLI arguments, 4) Environment variables, 5) Programmatic options. Control test execution, reporting, and behavior.
How do you implement custom reporters?
Custom reporters: 1) Extend Mocha's Base reporter, 2) Implement required methods, 3) Handle test events, 4) Format output as needed, 5) Register reporter with Mocha. Allows customized test reporting.
What are the best practices for test organization?
Organization practices: 1) Group related tests in describes, 2) Use clear test descriptions, 3) Maintain test independence, 4) Follow consistent naming, 5) Structure tests hierarchically. Improves maintainability.
How do you handle test data management?
Data management: 1) Use fixtures, 2) Implement data factories, 3) Clean up test data, 4) Isolate test data, 5) Manage data dependencies. Ensures reliable test execution.
How do you implement parallel test execution?
Parallel execution: 1) Use --parallel flag, 2) Configure worker count, 3) Handle shared resources, 4) Manage test isolation, 5) Consider file-level parallelization. Improves test execution speed.
What are advanced test filtering techniques?
Advanced filtering: 1) Use regex patterns, 2) Filter by suite/test name, 3) Implement custom grep, 4) Use test metadata, 5) Filter by file patterns. Helps focus test execution.
How do you implement custom test interfaces?
Custom interfaces: 1) Define interface methods, 2) Register with Mocha, 3) Handle test definition, 4) Manage context, 5) Support hooks and suites. Allows custom test syntax.
What are strategies for handling complex async flows?
Complex async handling: 1) Chain promises properly, 2) Manage async timeouts, 3) Handle parallel operations, 4) Control execution flow, 5) Implement proper error handling. Important for reliable async tests.
How do you implement test suite composition?
Suite composition: 1) Share common tests, 2) Extend test suites, 3) Compose test behaviors, 4) Manage suite hierarchy, 5) Handle shared context. Enables test reuse.
What are patterns for testing event emitters?
Event testing patterns: 1) Listen for events, 2) Verify event data, 3) Test event ordering, 4) Handle event timing, 5) Test error events. Important for event-driven code.
What assertion libraries can be used with Mocha?
Mocha supports multiple assertion libraries: 1) Node's built-in assert module, 2) Chai for BDD/TDD assertions, 3) Should.js for BDD style assertions, 4) Expect.js for expect() style assertions, 5) Better-assert for C-style assertions. Each offers different syntax and capabilities.
How do you use Chai assertions in Mocha?
Using Chai involves: 1) Installing: npm install chai, 2) Importing desired interface (expect, should, assert), 3) Writing assertions using chosen style, 4) Using chainable language constructs, 5) Handling async assertions. Example: const { expect } = require('chai'); expect(value).to.equal(expected);
What are the different assertion styles in Chai?
Chai offers three styles: 1) Assert - traditional TDD style (assert.equal()), 2) Expect - BDD style with expect() (expect().to), 3) Should - BDD style with should chaining (value.should). Each style has its own syntax and use cases.
How do you handle asynchronous assertions?
Async assertions handled through: 1) Using done callback, 2) Returning promises, 3) Async/await syntax, 4) Chai-as-promised for promise assertions, 5) Proper error handling. Example: it('async test', async () => { await expect(promise).to.be.fulfilled; });
What are the common assertion patterns in Mocha?
Common patterns include: 1) Equality checking (equal, strictEqual), 2) Type checking (typeOf, instanceOf), 3) Value comparison (greater, less), 4) Property checking (property, include), 5) Exception testing (throw). Use appropriate assertions for different scenarios.
How do you test exceptions with assertions?
Exception testing approaches: 1) expect(() => {}).to.throw(), 2) assert.throws(), 3) Testing specific error types, 4) Verifying error messages, 5) Handling async errors. Example: expect(() => fn()).to.throw(ErrorType, 'error message');
What are chainable assertions in Chai?
Chainable assertions allow: 1) Fluent interface with natural language, 2) Combining multiple checks, 3) Negating assertions with .not, 4) Adding semantic meaning, 5) Improving test readability. Example: expect(value).to.be.an('array').that.is.not.empty;
How do you test object properties?
Object property testing: 1) Check property existence, 2) Verify property values, 3) Test nested properties, 4) Compare object structures, 5) Check property types. Example: expect(obj).to.have.property('key').that.equals('value');
What are assertion plugins and how are they used?
Assertion plugins: 1) Extend assertion capabilities, 2) Add custom assertions, 3) Integrate with testing tools, 4) Provide domain-specific assertions, 5) Enhance assertion functionality. Example: chai-as-promised for promise assertions.
How do you handle deep equality assertions?
Deep equality testing: 1) Use deep.equal for objects/arrays, 2) Compare nested structures, 3) Handle circular references, 4) Check property order, 5) Consider type coercion. Example: expect(obj1).to.deep.equal(obj2);
How do you implement custom assertions?
Custom assertions: 1) Use Chai's addMethod/addProperty, 2) Define assertion logic, 3) Add chainable methods, 4) Include error messages, 5) Register with assertion library. Creates domain-specific assertions.
What are assertion best practices?
Best practices include: 1) Use specific assertions, 2) Write clear error messages, 3) Test one thing per assertion, 4) Handle edge cases, 5) Maintain assertion consistency. Improves test maintainability.
How do you test array operations?
Array testing patterns: 1) Check array contents, 2) Verify array length, 3) Test array ordering, 4) Check array modifications, 5) Test array methods. Example: expect(array).to.include.members([1, 2]);
What are patterns for testing promises?
Promise testing patterns: 1) Test resolution values, 2) Verify rejection reasons, 3) Check promise states, 4) Test promise chains, 5) Handle async operations. Use chai-as-promised for enhanced assertions.
How do you handle type checking assertions?
Type checking includes: 1) Verify primitive types, 2) Check object types, 3) Test instance types, 4) Validate type coercion, 5) Handle custom types. Example: expect(value).to.be.a('string');
What are patterns for testing events?
Event testing patterns: 1) Verify event emission, 2) Check event parameters, 3) Test event ordering, 4) Handle async events, 5) Test error events. Use event tracking and assertions.
How do you test conditional logic?
Conditional testing: 1) Test all branches, 2) Verify boundary conditions, 3) Check edge cases, 4) Test combinations, 5) Verify default cases. Ensure comprehensive coverage.
What are patterns for testing async/await?
Async/await patterns: 1) Handle async operations, 2) Test error conditions, 3) Chain async calls, 4) Verify async results, 5) Test concurrent operations. Use proper async assertions.
How do you handle assertion timeouts?
Timeout handling: 1) Set assertion timeouts, 2) Handle async timeouts, 3) Configure retry intervals, 4) Manage long-running assertions, 5) Handle timeout errors. Important for async tests.
What are patterns for testing error handling?
Error testing patterns: 1) Verify error types, 2) Check error messages, 3) Test error propagation, 4) Handle async errors, 5) Test error recovery. Ensure proper error handling.
How do you implement advanced assertion chaining?
Advanced chaining: 1) Combine multiple assertions, 2) Create complex conditions, 3) Handle async chains, 4) Manage state between assertions, 5) Create reusable chains. Enables sophisticated testing.
What are patterns for testing complex objects?
Complex object testing: 1) Test object hierarchies, 2) Verify object relationships, 3) Test object mutations, 4) Handle circular references, 5) Test object behaviors. Use appropriate assertions.
How do you handle assertion reporting?
Assertion reporting: 1) Customize error messages, 2) Format assertion output, 3) Group related assertions, 4) Handle assertion failures, 5) Generate assertion reports. Improves test feedback.
What are patterns for testing state machines?
State machine testing: 1) Test state transitions, 2) Verify state invariants, 3) Test invalid states, 4) Check state history, 5) Test concurrent states. Use appropriate assertions.
How do you implement property-based testing?
Property testing: 1) Define property checks, 2) Generate test cases, 3) Verify invariants, 4) Test property combinations, 5) Handle edge cases. Use libraries like jsverify.
What are patterns for testing concurrent operations?
Concurrent testing: 1) Test parallel execution, 2) Verify race conditions, 3) Test resource sharing, 4) Handle timeouts, 5) Test synchronization. Use appropriate async assertions.
What are the different types of hooks in Mocha?
Mocha provides four types of hooks: 1) before() - runs once before all tests, 2) beforeEach() - runs before each test, 3) after() - runs once after all tests, 4) afterEach() - runs after each test. Hooks help with setup and cleanup operations.
How do you handle asynchronous operations in hooks?
Async hooks can be handled through: 1) done callback, 2) returning promises, 3) async/await syntax, 4) proper error handling, 5) timeout management. Example: beforeEach(async () => { await setupDatabase(); });
What is the execution order of hooks in Mocha?
Hook execution order: 1) before() at suite level, 2) beforeEach() from outer to inner, 3) test execution, 4) afterEach() from inner to outer, 5) after() at suite level. Understanding order is crucial for proper setup/cleanup.
How do you share context between hooks and tests?
Context sharing methods: 1) Using this keyword, 2) Shared variables in closure, 3) Hook-specific context objects, 4) Global test context, 5) Proper scoping of shared resources. Example: beforeEach(function() { this.sharedData = 'test'; });
What is the purpose of describe blocks in test organization?
describe blocks serve to: 1) Group related tests, 2) Create test hierarchy, 3) Share setup/teardown code, 4) Organize test suites, 5) Provide context for tests. Helps maintain clear test structure.
How do you handle cleanup in hooks?
Cleanup handling: 1) Use afterEach/after hooks, 2) Clean shared resources, 3) Reset state between tests, 4) Handle async cleanup, 5) Ensure proper error handling. Important for test isolation.
What are root level hooks?
Root level hooks: 1) Apply to all test files, 2) Set up global before/after hooks, 3) Handle common setup/teardown, 4) Manage shared resources, 5) Configure test environment. Used for project-wide setup.
How do you handle errors in hooks?
Hook error handling: 1) Try-catch blocks in hooks, 2) Promise error handling, 3) Error reporting in hooks, 4) Cleanup after errors, 5) Proper test failure handling. Ensures reliable test execution.
What are best practices for hook usage?
Hook best practices: 1) Keep hooks focused, 2) Minimize hook complexity, 3) Clean up resources properly, 4) Handle async operations correctly, 5) Maintain hook independence. Improves test maintainability.
How do you handle timeouts in hooks?
Hook timeout handling: 1) Set hook-specific timeouts, 2) Configure global timeouts, 3) Handle async timeouts, 4) Manage long-running operations, 5) Proper timeout error handling. Example: before(function() { this.timeout(5000); });
How do you implement nested describe blocks?
Nested describes: 1) Create test hierarchies, 2) Share context between levels, 3) Organize related tests, 4) Handle nested hooks properly, 5) Maintain clear structure. Helps organize complex test suites.
What are patterns for sharing test fixtures?
Fixture sharing patterns: 1) Use before hooks for setup, 2) Implement fixture factories, 3) Share through context, 4) Manage fixture lifecycle, 5) Clean up fixtures properly. Ensures consistent test data.
How do you handle dynamic test generation?
Dynamic test generation: 1) Generate tests in loops, 2) Create tests from data, 3) Handle dynamic describes, 4) Manage test context, 5) Ensure proper isolation. Useful for data-driven tests.
What are strategies for managing test state?
State management strategies: 1) Use hooks for state setup, 2) Clean state between tests, 3) Isolate test state, 4) Handle shared state, 5) Manage state dependencies. Important for test reliability.
How do you implement test helpers?
Test helper implementation: 1) Create helper functions, 2) Share common utilities, 3) Manage helper state, 4) Handle helper errors, 5) Document helper usage. Improves test code reuse.
What are patterns for testing async hooks?
Async hook patterns: 1) Handle promise chains, 2) Manage async operations, 3) Control execution flow, 4) Handle timeouts, 5) Proper error handling. Important for reliable async setup/teardown.
How do you organize large test suites?
Large suite organization: 1) Group by feature/module, 2) Use nested describes, 3) Share common setup, 4) Maintain clear structure, 5) Document organization. Improves test maintainability.
What are best practices for hook error handling?
Error handling practices: 1) Proper try-catch usage, 2) Error reporting in hooks, 3) Cleanup after errors, 4) Error propagation handling, 5) Test failure management. Ensures reliable test execution.
How do you handle conditional tests?
Conditional test handling: 1) Skip tests conditionally, 2) Run specific tests, 3) Handle environment conditions, 4) Manage test flags, 5) Document conditions. Enables flexible test execution.
What are patterns for hook composition?
Hook composition patterns: 1) Combine multiple hooks, 2) Share hook functionality, 3) Create reusable hooks, 4) Manage hook dependencies, 5) Handle hook ordering. Enables modular test setup.
How do you implement advanced test organization patterns?
Advanced patterns: 1) Custom test structures, 2) Dynamic suite generation, 3) Complex test hierarchies, 4) Shared behavior patterns, 5) Test composition strategies. Enables sophisticated test organization.
What are strategies for testing complex workflows?
Complex workflow testing: 1) Break down into steps, 2) Manage state transitions, 3) Handle async flows, 4) Test error paths, 5) Verify workflow completion. Ensures comprehensive testing.
How do you implement test suite inheritance?
Suite inheritance: 1) Share common tests, 2) Extend base suites, 3) Override specific tests, 4) Manage shared context, 5) Handle hook inheritance. Enables test reuse.
What are patterns for testing state machines?
State machine testing: 1) Test state transitions, 2) Verify state invariants, 3) Test invalid states, 4) Handle async states, 5) Test state history. Ensures proper state handling.
How do you implement custom test interfaces?
Custom interfaces: 1) Define interface API, 2) Implement test organization, 3) Handle hook integration, 4) Manage context, 5) Support async operations. Enables custom testing patterns.
What are strategies for testing distributed systems?
Distributed testing: 1) Coordinate multiple components, 2) Handle async communication, 3) Test system integration, 4) Manage distributed state, 5) Test failure scenarios. Ensures system-wide testing.
How do you implement advanced hook patterns?
Advanced hook patterns: 1) Dynamic hook generation, 2) Conditional hook execution, 3) Hook composition, 4) Hook middleware, 5) Hook state management. Enables sophisticated setup/teardown.
What are the different ways to handle asynchronous tests in Mocha?
Mocha supports multiple async patterns: 1) Using done callback, 2) Returning promises, 3) async/await syntax, 4) Using setTimeout/setInterval, 5) Event-based async. Example: it('async test', (done) => { asyncOperation(() => { done(); }); });
How does the done callback work in Mocha?
done callback: 1) Signals test completion, 2) Must be called exactly once, 3) Can pass error as argument, 4) Has timeout protection, 5) Used for callback-style async code. Test fails if done isn't called or called multiple times.
How do you test promises in Mocha?
Promise testing: 1) Return promise from test, 2) Chain .then() and .catch(), 3) Use promise assertions, 4) Handle rejection cases, 5) Test promise states. Example: return Promise.resolve().then(result => assert(result));
How do you use async/await in Mocha tests?
async/await usage: 1) Mark test function as async, 2) Use await for async operations, 3) Handle errors with try/catch, 4) Chain multiple await calls, 5) Maintain proper error handling. Example: it('async test', async () => { const result = await asyncOp(); });
How do you handle timeouts in async tests?
Timeout handling: 1) Set test timeout with this.timeout(), 2) Configure global timeouts, 3) Handle slow tests appropriately, 4) Set different timeouts for different environments, 5) Proper error handling for timeouts.
What are common pitfalls in async testing?
Common pitfalls: 1) Forgetting to return promises, 2) Missing done() calls, 3) Multiple done() calls, 4) Improper error handling, 5) Race conditions. Understanding these helps write reliable async tests.
How do you test event emitters asynchronously?
Event testing: 1) Listen for events with done, 2) Set appropriate timeouts, 3) Verify event data, 4) Handle multiple events, 5) Test error events. Example: emitter.once('event', () => done());
What is the purpose of async hooks in Mocha?
Async hooks: 1) Setup async resources, 2) Clean up async operations, 3) Handle async dependencies, 4) Manage async state, 5) Ensure proper test isolation. Used for async setup/teardown.
How do you handle sequential async operations?
Sequential handling: 1) Chain promises properly, 2) Use async/await, 3) Maintain operation order, 4) Handle errors in sequence, 5) Verify sequential results. Ensures correct operation order.
What are best practices for async testing?
Best practices: 1) Always handle errors, 2) Set appropriate timeouts, 3) Clean up resources, 4) Avoid nested callbacks, 5) Use modern async patterns. Ensures reliable async tests.
How do you test promise chains?
Promise chain testing: 1) Return entire chain, 2) Test intermediate results, 3) Handle chain errors, 4) Verify chain order, 5) Test chain completion. Example: return promise.then().then();
What are patterns for testing parallel operations?
Parallel testing: 1) Use Promise.all(), 2) Handle concurrent operations, 3) Manage shared resources, 4) Test race conditions, 5) Verify parallel results. Ensures proper concurrent execution.
How do you test async error conditions?
Async error testing: 1) Test rejection cases, 2) Verify error types, 3) Check error messages, 4) Test error propagation, 5) Handle error recovery. Important for error handling.
What are strategies for testing async timeouts?
Timeout strategies: 1) Set test timeouts, 2) Test timeout handling, 3) Verify timeout behavior, 4) Handle long operations, 5) Test timeout recovery. Ensures proper timeout handling.
How do you handle async state management?
Async state management: 1) Track async state changes, 2) Verify state transitions, 3) Handle state errors, 4) Test state consistency, 5) Manage state cleanup. Important for state-dependent tests.
What are patterns for testing async streams?
Stream testing: 1) Test stream events, 2) Verify stream data, 3) Handle stream errors, 4) Test backpressure, 5) Verify stream completion. Important for streaming operations.
How do you test async iterators?
Iterator testing: 1) Test async iteration, 2) Verify iterator results, 3) Handle iterator errors, 4) Test completion, 5) Verify iteration order. Important for async collections.
What are approaches for testing async queues?
Queue testing: 1) Test queue operations, 2) Verify queue order, 3) Handle queue errors, 4) Test queue capacity, 5) Verify queue completion. Important for queue-based systems.
How do you test async hooks?
Hook testing: 1) Test hook execution, 2) Verify hook timing, 3) Handle hook errors, 4) Test hook cleanup, 5) Verify hook order. Important for async lifecycle management.
What are patterns for testing complex async workflows?
Complex workflow testing: 1) Break down into steps, 2) Test state transitions, 3) Verify workflow order, 4) Handle errors, 5) Test completion. Important for multi-step processes.
How do you implement advanced async patterns?
Advanced patterns: 1) Custom async utilities, 2) Complex async flows, 3) Async composition, 4) Error recovery strategies, 5) Performance optimization. Enables sophisticated async testing.
What are strategies for testing distributed async systems?
Distributed testing: 1) Test network operations, 2) Handle distributed state, 3) Test consistency, 4) Verify synchronization, 5) Handle partitions. Important for distributed systems.
How do you test async performance?
Performance testing: 1) Measure async operations, 2) Test concurrency limits, 3) Verify timing constraints, 4) Handle resource usage, 5) Test scalability. Important for system performance.
What are patterns for testing async recovery?
Recovery testing: 1) Test failure scenarios, 2) Verify recovery steps, 3) Handle partial failures, 4) Test retry logic, 5) Verify system stability. Important for system resilience.
How do you implement async test monitoring?
Test monitoring: 1) Track async operations, 2) Monitor resource usage, 3) Collect metrics, 4) Analyze performance, 5) Generate reports. Important for test observability.
What are strategies for testing async security?
Security testing: 1) Test authentication flows, 2) Verify authorization, 3) Test secure communication, 4) Handle security timeouts, 5) Verify secure state. Important for system security.
How do you test async compliance requirements?
Compliance testing: 1) Verify timing requirements, 2) Test audit trails, 3) Handle data retention, 4) Test logging, 5) Verify compliance rules. Important for regulatory compliance.
What is the difference between mocks and stubs?
Key differences include: 1) Stubs provide canned answers to calls, 2) Mocks verify behavior and interactions, 3) Stubs don't typically fail tests, 4) Mocks can fail tests if expected behavior doesn't occur, 5) Stubs are simpler and used for state testing while mocks are used for behavior testing.
What mocking libraries can be used with Mocha?
Common mocking libraries: 1) Sinon.js for comprehensive mocking, 2) Jest mocks when using Jest, 3) testdouble.js for test doubles, 4) Proxyquire for module mocking, 5) Nock for HTTP mocking. Each has specific use cases and features.
How do you create a basic stub with Sinon?
Creating stubs with Sinon: 1) sinon.stub() creates stub function, 2) .returns() sets return value, 3) .throws() makes stub throw error, 4) .callsFake() provides implementation, 5) .resolves()/.rejects() for promises. Example: const stub = sinon.stub().returns('value');
What are spies and how are they used?
Spies are used to: 1) Track function calls, 2) Record arguments, 3) Check call count, 4) Verify call order, 5) Monitor return values. Example: const spy = sinon.spy(object, 'method'); Test wraps existing functions without changing behavior.
How do you mock HTTP requests?
HTTP mocking approaches: 1) Use Nock for HTTP mocks, 2) Mock fetch/axios globally, 3) Stub specific endpoints, 4) Mock response data, 5) Simulate network errors. Example: nock('http://api.example.com').get('/data').reply(200, { data: 'value' });
What is module mocking and how is it implemented?
Module mocking involves: 1) Using Proxyquire or similar tools, 2) Replacing module dependencies, 3) Mocking specific exports, 4) Maintaining module interface, 5) Handling module side effects. Helps isolate code under test.
How do you verify mock/stub calls?
Call verification includes: 1) Check call count with calledOnce/Twice, 2) Verify arguments with calledWith, 3) Check call order with calledBefore/After, 4) Verify call context with calledOn, 5) Assert on return values.
What are sandboxes in Sinon and why use them?
Sinon sandboxes: 1) Group mocks/stubs together, 2) Provide automatic cleanup, 3) Isolate test setup, 4) Prevent mock leakage, 5) Simplify test maintenance. Example: const sandbox = sinon.createSandbox(); sandbox.restore();
How do you handle mock cleanup?
Mock cleanup approaches: 1) Use afterEach hooks, 2) Implement sandbox restoration, 3) Reset individual mocks, 4) Clean up module mocks, 5) Restore original implementations. Prevents test interference.
What are fake timers and how are they used?
Fake timers: 1) Mock Date/setTimeout/setInterval, 2) Control time progression, 3) Test time-dependent code, 4) Simulate delays without waiting, 5) Handle timer cleanup. Example: sinon.useFakeTimers();
How do you mock promises with Sinon?
Promise mocking: 1) Use stub.resolves() for success, 2) Use stub.rejects() for failure, 3) Chain promise behavior, 4) Mock async operations, 5) Test error handling. Example: stub.resolves('value');
What are strategies for mocking databases?
Database mocking: 1) Mock database drivers, 2) Stub query methods, 3) Mock connection pools, 4) Simulate database errors, 5) Handle transactions. Isolates tests from actual database.
How do you mock file system operations?
File system mocking: 1) Mock fs module, 2) Stub file operations, 3) Simulate file errors, 4) Mock file content, 5) Handle async operations. Example: using mock-fs or similar libraries.
What are patterns for mocking event emitters?
Event emitter mocking: 1) Stub emit methods, 2) Mock event handlers, 3) Simulate event sequences, 4) Test error events, 5) Verify event data. Important for event-driven code.
How do you mock external APIs?
API mocking approaches: 1) Use HTTP mocking libraries, 2) Mock API clients, 3) Simulate API responses, 4) Handle API errors, 5) Mock authentication. Isolates from external dependencies.
What are strategies for mocking WebSocket connections?
WebSocket mocking: 1) Mock socket events, 2) Simulate messages, 3) Test connection states, 4) Handle disconnects, 5) Mock real-time data. Important for real-time applications.
How do you handle partial mocking?
Partial mocking: 1) Mock specific methods, 2) Keep original behavior, 3) Combine real/mock functionality, 4) Control mock scope, 5) Handle method dependencies. Useful for complex objects.
What are patterns for mocking class instances?
Instance mocking: 1) Mock constructors, 2) Stub instance methods, 3) Mock inheritance chain, 4) Handle static methods, 5) Mock instance properties. Important for OOP testing.
How do you mock environment variables?
Environment mocking: 1) Mock process.env, 2) Stub configuration, 3) Handle different environments, 4) Restore original values, 5) Mock system info. Important for configuration testing.
How do you implement advanced mock behaviors?
Advanced behaviors: 1) Dynamic responses, 2) Conditional mocking, 3) State-based responses, 4) Complex interactions, 5) Chainable behaviors. Enables sophisticated testing scenarios.
What are strategies for mocking microservices?
Microservice mocking: 1) Mock service communication, 2) Simulate service failures, 3) Test service discovery, 4) Mock service registry, 5) Handle distributed state. Important for distributed systems.
How do you implement custom mock factories?
Mock factories: 1) Create reusable mocks, 2) Generate test data, 3) Configure mock behavior, 4) Handle mock lifecycle, 5) Maintain mock consistency. Improves test maintainability.
What are patterns for mocking streaming data?
Stream mocking: 1) Mock stream events, 2) Simulate data flow, 3) Test backpressure, 4) Handle stream errors, 5) Mock transformations. Important for stream processing.
How do you mock complex authentication flows?
Auth flow mocking: 1) Mock auth providers, 2) Simulate tokens, 3) Test permissions, 4) Mock sessions, 5) Handle auth errors. Important for security testing.
What are strategies for mocking native modules?
Native module mocking: 1) Mock binary modules, 2) Handle platform specifics, 3) Mock system calls, 4) Test native interfaces, 5) Handle compilation. Important for low-level testing.
How do you implement mock monitoring?
Mock monitoring: 1) Track mock usage, 2) Monitor interactions, 3) Collect metrics, 4) Analyze patterns, 5) Generate reports. Important for test analysis.
What are the best practices for organizing test files?
Best practices include: 1) Mirror source code structure, 2) Use consistent naming conventions (.test.js, .spec.js), 3) Group related tests together, 4) Maintain test independence, 5) Keep test files focused and manageable, 6) Use descriptive file names.
How should describe blocks be structured?
describe blocks should: 1) Group related test cases, 2) Follow logical hierarchy, 3) Use clear, descriptive names, 4) Maintain proper nesting levels, 5) Share common setup when appropriate. Example: describe('User Authentication', () => { describe('Login', () => {});
What are the guidelines for writing test descriptions?
Test descriptions should: 1) Be clear and specific, 2) Describe expected behavior, 3) Use consistent terminology, 4) Follow 'it should...' pattern, 5) Be readable as complete sentences. Example: it('should return error for invalid input')
How do you handle test dependencies?
Handle dependencies by: 1) Using before/beforeEach hooks, 2) Creating shared fixtures, 3) Implementing test helpers, 4) Managing shared state carefully, 5) Cleaning up after tests. Ensures test isolation.
What is the purpose of test hooks in organization?
Test hooks serve to: 1) Set up test prerequisites, 2) Clean up after tests, 3) Share common setup logic, 4) Manage test resources, 5) Maintain test isolation. Example: beforeEach(), afterEach() for setup/cleanup.
How should test utilities be organized?
Test utilities should be: 1) Placed in separate helper files, 2) Grouped by functionality, 3) Made reusable across tests, 4) Well-documented, 5) Easy to maintain. Helps reduce code duplication.
What is the role of test fixtures?
Test fixtures: 1) Provide test data, 2) Set up test environment, 3) Ensure consistent test state, 4) Reduce setup duplication, 5) Make tests maintainable. Example: JSON files with test data.
How do you maintain test independence?
Maintain independence by: 1) Cleaning up after each test, 2) Avoiding shared state, 3) Using fresh fixtures, 4) Isolating test environments, 5) Proper hook usage. Prevents test interference.
What are common test file naming conventions?
Common conventions: 1) .test.js suffix, 2) .spec.js suffix, 3) Match source file names, 4) Use descriptive prefixes, 5) Group related tests. Example: user.test.js for user.js tests.
How should test configurations be managed?
Config management: 1) Use .mocharc.js file, 2) Separate environment configs, 3) Manage test timeouts, 4) Set reporter options, 5) Handle CLI arguments. Ensures consistent test execution.
How do you implement test suites for large applications?
Large app testing: 1) Organize by feature/module, 2) Use nested describes, 3) Share common utilities, 4) Implement proper separation, 5) Maintain clear structure. Improves maintainability.
What are patterns for sharing test code?
Code sharing patterns: 1) Create helper modules, 2) Use shared fixtures, 3) Implement common utilities, 4) Create test base classes, 5) Use composition over inheritance. Reduces duplication.
How do you manage test environments?
Environment management: 1) Configure per environment, 2) Handle environment variables, 3) Set up test databases, 4) Manage external services, 5) Control test data. Ensures consistent testing.
What are strategies for test data management?
Data management: 1) Use fixtures effectively, 2) Implement data factories, 3) Clean up test data, 4) Handle data dependencies, 5) Maintain data isolation. Ensures reliable tests.
How should integration tests be organized?
Integration test organization: 1) Separate from unit tests, 2) Group by feature, 3) Handle dependencies properly, 4) Manage test order, 5) Control test environment. Ensures comprehensive testing.
What are patterns for test retry logic?
Retry patterns: 1) Configure retry attempts, 2) Handle flaky tests, 3) Implement backoff strategy, 4) Log retry attempts, 5) Monitor retry patterns. Improves test reliability.
How do you handle cross-cutting test concerns?
Cross-cutting concerns: 1) Implement test middleware, 2) Use global hooks, 3) Share common behavior, 4) Handle logging/monitoring, 5) Manage error handling. Ensures consistent behavior.
What are best practices for test documentation?
Documentation practices: 1) Write clear descriptions, 2) Document test setup, 3) Explain test rationale, 4) Maintain API docs, 5) Update documentation regularly. Improves test understanding.
How do you manage test timeouts?
Timeout management: 1) Set appropriate timeouts, 2) Configure per test/suite, 3) Handle async operations, 4) Monitor slow tests, 5) Implement timeout strategies. Ensures reliable execution.
How do you implement advanced test organization patterns?
Advanced patterns: 1) Custom test structures, 2) Complex test hierarchies, 3) Shared behavior specs, 4) Test composition, 5) Dynamic test generation. Enables sophisticated testing.
What are strategies for testing microservices?
Microservice testing: 1) Service isolation, 2) Contract testing, 3) Integration patterns, 4) Service mocking, 5) Distributed testing. Important for service architecture.
How do you implement test monitoring?
Test monitoring: 1) Track execution metrics, 2) Monitor performance, 3) Log test data, 4) Analyze patterns, 5) Generate reports. Important for test maintenance.
What are patterns for test suite optimization?
Suite optimization: 1) Parallel execution, 2) Test grouping, 3) Resource management, 4) Cache utilization, 5) Performance tuning. Improves execution efficiency.
How do you handle complex test dependencies?
Complex dependencies: 1) Dependency injection, 2) Service locator pattern, 3) Mock factories, 4) State management, 5) Cleanup strategies. Important for large systems.
What are strategies for test data factories?
Data factory strategies: 1) Factory patterns, 2) Data generation, 3) State management, 4) Relationship handling, 5) Cleanup procedures. Important for test data management.
How do you implement test composition?
Test composition: 1) Shared behaviors, 2) Test mixins, 3) Behavior composition, 4) Context sharing, 5) State management. Enables reusable test patterns.
What are patterns for distributed testing?
Distributed testing: 1) Service coordination, 2) State synchronization, 3) Resource management, 4) Error handling, 5) Result aggregation. Important for distributed systems.
How do you implement custom test runners?
Custom runners: 1) Runner implementation, 2) Test discovery, 3) Execution control, 4) Result reporting, 5) Configuration management. Enables specialized test execution.
What factors affect test execution speed in Mocha?
Key factors include: 1) Number and complexity of tests, 2) Async operation handling, 3) Test setup/teardown overhead, 4) File I/O operations, 5) Database interactions, 6) Network requests, 7) Resource cleanup efficiency.
How can you measure test execution time?
Measuring methods: 1) Use --reporter spec for timing info, 2) Implement custom reporters for timing, 3) Use console.time/timeEnd, 4) Track slow tests with --slow flag, 5) Monitor hook execution time.
What are best practices for optimizing test setup?
Setup optimization: 1) Use beforeAll for one-time setup, 2) Minimize per-test setup, 3) Share setup when possible, 4) Cache test resources, 5) Use efficient data creation methods.
How do you identify slow tests?
Identification methods: 1) Use --slow flag to mark slow tests, 2) Implement timing reporters, 3) Monitor test duration, 4) Profile test execution, 5) Track resource usage. Example: mocha --slow 75.
What is the impact of hooks on test performance?
Hook impacts: 1) Setup/teardown overhead, 2) Resource allocation costs, 3) Database operation time, 4) File system operations, 5) Network request delays. Optimize hooks for better performance.
How can test parallelization improve performance?
Parallelization benefits: 1) Reduced total execution time, 2) Better resource utilization, 3) Concurrent test execution, 4) Improved CI/CD pipeline speed, 5) Efficient test distribution.
What is the role of timeouts in test performance?
Timeout considerations: 1) Default timeout settings, 2) Per-test timeouts, 3) Hook timeouts, 4) Async operation timing, 5) Timeout impact on test speed. Balance between reliability and speed.
How do you optimize async test execution?
Async optimization: 1) Use proper async patterns, 2) Avoid unnecessary waiting, 3) Implement efficient promises, 4) Handle concurrent operations, 5) Optimize async cleanup.
What impact does mocking have on performance?
Mocking impacts: 1) Mock creation overhead, 2) Stub implementation efficiency, 3) Mock cleanup costs, 4) Memory usage, 5) Mock verification time. Balance between isolation and performance.
How can test data management affect performance?
Data management impacts: 1) Data creation time, 2) Cleanup overhead, 3) Database operations, 4) Memory usage, 5) I/O operations. Optimize data handling for better performance.
What strategies exist for optimizing test suites?
Suite optimization: 1) Group related tests, 2) Implement efficient setup, 3) Optimize resource usage, 4) Use proper test isolation, 5) Implement caching strategies.
How do you optimize database operations in tests?
Database optimization: 1) Use transactions, 2) Batch operations, 3) Implement connection pooling, 4) Cache query results, 5) Minimize database calls.
What are patterns for optimizing file I/O?
I/O optimization: 1) Minimize file operations, 2) Use buffers efficiently, 3) Implement caching, 4) Batch file operations, 5) Use streams when appropriate.
How can memory usage be optimized?
Memory optimization: 1) Proper resource cleanup, 2) Minimize object creation, 3) Handle large datasets efficiently, 4) Implement garbage collection, 5) Monitor memory leaks.
What strategies exist for optimizing network requests?
Network optimization: 1) Mock network calls, 2) Cache responses, 3) Batch requests, 4) Implement request pooling, 5) Use efficient protocols.
How do you optimize test reporters?
Reporter optimization: 1) Use efficient output formats, 2) Minimize logging, 3) Implement async reporting, 4) Optimize data collection, 5) Handle large test suites.
What are approaches for optimizing test fixtures?
Fixture optimization: 1) Implement fixture caching, 2) Minimize setup costs, 3) Share fixtures when possible, 4) Efficient cleanup, 5) Optimize data generation.
How can hook execution be optimized?
Hook optimization: 1) Minimize hook operations, 2) Share setup when possible, 3) Implement efficient cleanup, 4) Use appropriate hook types, 5) Optimize async hooks.
What patterns exist for optimizing assertion execution?
Assertion optimization: 1) Use efficient matchers, 2) Minimize assertion count, 3) Implement custom matchers, 4) Optimize async assertions, 5) Handle complex comparisons.
How do you handle performance profiling?
Profiling approaches: 1) Use Node.js profiler, 2) Implement custom profiling, 3) Monitor execution times, 4) Track resource usage, 5) Analyze bottlenecks.
What advanced strategies exist for test parallelization?
Advanced parallelization: 1) Custom worker pools, 2) Load balancing, 3) Resource coordination, 4) State management, 5) Result aggregation.
How do you optimize distributed test execution?
Distributed optimization: 1) Service coordination, 2) Resource allocation, 3) Network optimization, 4) State synchronization, 5) Result collection.
What are patterns for optimizing large test suites?
Large suite optimization: 1) Test segmentation, 2) Resource management, 3) Execution planning, 4) Cache strategies, 5) Performance monitoring.
How do you implement custom performance monitoring?
Custom monitoring: 1) Metric collection, 2) Performance analysis, 3) Resource tracking, 4) Alert systems, 5) Reporting tools.
What strategies exist for optimizing test data factories?
Factory optimization: 1) Efficient data generation, 2) Caching strategies, 3) Resource management, 4) Memory optimization, 5) Cleanup procedures.
How do you optimize test execution in CI/CD?
CI/CD optimization: 1) Pipeline optimization, 2) Resource allocation, 3) Cache utilization, 4) Parallel execution, 5) Result handling.
What are approaches for optimizing test runners?
Runner optimization: 1) Custom runner implementation, 2) Execution optimization, 3) Resource management, 4) Result collection, 5) Performance tuning.
How do you implement performance benchmarking?
Benchmarking implementation: 1) Metric definition, 2) Measurement tools, 3) Analysis methods, 4) Comparison strategies, 5) Reporting systems.
What are patterns for optimizing test frameworks?
Framework optimization: 1) Architecture improvements, 2) Resource efficiency, 3) Execution optimization, 4) Plugin management, 5) Performance tuning.
What is integration testing and how does it differ from unit testing?
Integration testing involves: 1) Testing multiple components together, 2) Verifying component interactions, 3) Testing external dependencies, 4) End-to-end functionality verification, 5) Testing real subsystems. Unlike unit tests, integration tests focus on component interactions rather than isolated functionality.
How do you set up integration tests in Mocha?
Setup involves: 1) Configuring test environment, 2) Setting up test databases, 3) Managing external services, 4) Handling test data, 5) Configuring proper timeouts. Example: separate test configuration for integration tests.
What are common integration test patterns?
Common patterns include: 1) Database integration testing, 2) API endpoint testing, 3) Service integration testing, 4) External service testing, 5) Component interaction testing. Focus on testing integrated functionality.
How do you handle test data in integration tests?
Test data handling: 1) Use test databases, 2) Implement data seeding, 3) Clean up test data, 4) Manage test state, 5) Handle data dependencies. Ensures reliable test execution.
What are best practices for database integration testing?
Database testing practices: 1) Use separate test database, 2) Implement transactions, 3) Clean up after tests, 4) Handle migrations, 5) Manage connections efficiently. Ensures data integrity.
How do you test API endpoints?
API testing involves: 1) Making HTTP requests, 2) Verifying responses, 3) Testing error cases, 4) Checking headers/status codes, 5) Testing authentication. Example: using supertest or axios.
What are strategies for handling external services?
External service strategies: 1) Use test doubles when needed, 2) Configure test endpoints, 3) Handle authentication, 4) Manage service state, 5) Handle network issues.
How do you ensure test isolation in integration tests?
Test isolation methods: 1) Clean database between tests, 2) Reset service state, 3) Use transactions, 4) Implement proper teardown, 5) Handle shared resources.
What role do hooks play in integration testing?
Hooks are used for: 1) Setting up test environment, 2) Database preparation, 3) Service initialization, 4) Resource cleanup, 5) State management. Critical for test setup/teardown.
How do you handle asynchronous operations in integration tests?
Async handling includes: 1) Using async/await, 2) Proper timeout configuration, 3) Handling promises, 4) Managing concurrent operations, 5) Error handling.
What are strategies for testing service interactions?
Service testing strategies: 1) Test service boundaries, 2) Verify data flow, 3) Test error conditions, 4) Handle service dependencies, 5) Test service lifecycle.
How do you handle complex data flows?
Data flow handling: 1) Test data transformations, 2) Verify state changes, 3) Test data consistency, 4) Handle data dependencies, 5) Manage data lifecycle.
What are patterns for testing middleware?
Middleware testing: 1) Test request processing, 2) Verify middleware chain, 3) Test error handling, 4) Check modifications, 5) Test order dependencies.
How do you test authentication flows?
Auth testing includes: 1) Test login processes, 2) Verify token handling, 3) Test permissions, 4) Check session management, 5) Test auth failures.
What are strategies for testing transactions?
Transaction testing: 1) Test commit behavior, 2) Verify rollbacks, 3) Test isolation levels, 4) Handle nested transactions, 5) Test concurrent access.
How do you test caching mechanisms?
Cache testing: 1) Verify cache hits/misses, 2) Test invalidation, 3) Check cache consistency, 4) Test cache policies, 5) Handle cache failures.
What are patterns for testing event systems?
Event testing patterns: 1) Test event emission, 2) Verify handlers, 3) Test event order, 4) Check event data, 5) Test error events.
How do you test data migrations?
Migration testing: 1) Test upgrade paths, 2) Verify data integrity, 3) Test rollbacks, 4) Check data transforms, 5) Handle migration errors.
What are approaches for testing queues?
Queue testing: 1) Test message flow, 2) Verify processing, 3) Test error handling, 4) Check queue state, 5) Test concurrent access.
How do you handle configuration testing?
Config testing: 1) Test different environments, 2) Verify config loading, 3) Test defaults, 4) Check validation, 5) Test config changes.
What are advanced patterns for testing microservices?
Microservice patterns: 1) Test service mesh, 2) Verify service discovery, 3) Test resilience, 4) Check scaling, 5) Test service communication.
How do you implement contract testing?
Contract testing: 1) Define service contracts, 2) Test API compatibility, 3) Verify schema changes, 4) Test versioning, 5) Handle contract violations.
What are strategies for testing distributed systems?
Distributed testing: 1) Test network partitions, 2) Verify consistency, 3) Test recovery, 4) Handle latency, 5) Test scalability.
How do you test eventual consistency?
Consistency testing: 1) Test sync mechanisms, 2) Verify convergence, 3) Test conflict resolution, 4) Check data propagation, 5) Handle timing issues.
What are patterns for testing system resilience?
Resilience testing: 1) Test failure modes, 2) Verify recovery, 3) Test degraded operation, 4) Check failover, 5) Test self-healing.
How do you implement chaos testing?
Chaos testing: 1) Inject failures, 2) Test system response, 3) Verify recovery, 4) Check data integrity, 5) Test service resilience.
What are strategies for testing scalability?
Scalability testing: 1) Test load handling, 2) Verify resource scaling, 3) Test performance, 4) Check bottlenecks, 5) Test capacity limits.
How do you test system boundaries?
Boundary testing: 1) Test interfaces, 2) Verify protocols, 3) Test data formats, 4) Check error handling, 5) Test integration points.
What are patterns for testing system upgrades?
Upgrade testing: 1) Test version compatibility, 2) Verify data migration, 3) Test rollback procedures, 4) Check system stability, 5) Test upgrade process.
How do you implement observability testing?
Observability testing: 1) Test monitoring systems, 2) Verify metrics collection, 3) Test logging, 4) Check tracing, 5) Test alerting.
What is security testing in Mocha and why is it important?
Security testing involves: 1) Testing authentication mechanisms, 2) Verifying authorization controls, 3) Testing input validation, 4) Checking data protection, 5) Testing against common vulnerabilities. Important for ensuring application security and protecting user data.
How do you test authentication in Mocha?
Authentication testing includes: 1) Testing login functionality, 2) Verifying token handling, 3) Testing session management, 4) Checking password policies, 5) Testing multi-factor authentication. Example: test invalid credentials, token expiration.
What are best practices for testing authorization?
Authorization testing practices: 1) Test role-based access, 2) Verify permission levels, 3) Check resource access, 4) Test access denial, 5) Verify resource isolation. Ensures proper access control.
How do you test input validation?
Input validation testing: 1) Test for XSS attacks, 2) Check SQL injection, 3) Validate data formats, 4) Test boundary conditions, 5) Check sanitization. Prevents malicious input.
What are common security test patterns?
Common patterns include: 1) Authentication testing, 2) Authorization checks, 3) Input validation, 4) Session management, 5) Data protection testing. Forms basis of security testing.
How do you test session management?
Session testing involves: 1) Test session creation, 2) Verify session expiration, 3) Check session isolation, 4) Test concurrent sessions, 5) Verify session invalidation.
What is CSRF testing and how is it implemented?
CSRF testing includes: 1) Verify token presence, 2) Test token validation, 3) Check token renewal, 4) Test request forgery scenarios, 5) Verify protection mechanisms.
How do you test password security?
Password security testing: 1) Test password policies, 2) Check hashing implementation, 3) Verify password reset, 4) Test password change, 5) Check against common vulnerabilities.
What are approaches for testing data encryption?
Encryption testing: 1) Verify data encryption, 2) Test key management, 3) Check encrypted storage, 4) Test encrypted transmission, 5) Verify decryption process.
How do you test error handling for security?
Security error testing: 1) Test error messages, 2) Check information disclosure, 3) Verify error logging, 4) Test error recovery, 5) Check security breach handling.
What are strategies for testing API security?
API security testing: 1) Test authentication, 2) Verify rate limiting, 3) Check input validation, 4) Test error handling, 5) Verify data protection. Ensures secure API endpoints.
How do you test OAuth implementations?
OAuth testing includes: 1) Test authorization flow, 2) Verify token handling, 3) Check scope validation, 4) Test token refresh, 5) Verify client authentication.
What are patterns for testing JWT security?
JWT security testing: 1) Verify token signing, 2) Test token validation, 3) Check expiration handling, 4) Test payload security, 5) Verify token storage.
How do you test role-based access control?
RBAC testing: 1) Test role assignments, 2) Verify permission inheritance, 3) Check access restrictions, 4) Test role hierarchy, 5) Verify role changes.
What are approaches for testing secure communication?
Secure communication testing: 1) Test SSL/TLS, 2) Verify certificate validation, 3) Check protocol security, 4) Test secure headers, 5) Verify encryption.
How do you test file upload security?
File upload security: 1) Test file validation, 2) Check file types, 3) Verify size limits, 4) Test malicious files, 5) Check storage security.
What are patterns for testing data validation?
Data validation testing: 1) Test input sanitization, 2) Check type validation, 3) Verify format checking, 4) Test boundary values, 5) Check validation bypass.
How do you test security headers?
Security header testing: 1) Verify CORS headers, 2) Check CSP implementation, 3) Test XSS protection, 4) Verify HSTS, 5) Test frame options.
What are strategies for testing secure storage?
Secure storage testing: 1) Test data encryption, 2) Verify access control, 3) Check data isolation, 4) Test backup security, 5) Verify deletion.
How do you test security logging?
Security logging tests: 1) Verify audit trails, 2) Check log integrity, 3) Test log access, 4) Verify event logging, 5) Test log rotation.
What are advanced patterns for penetration testing?
Advanced pen testing: 1) Test injection attacks, 2) Check vulnerability chains, 3) Test security bypasses, 4) Verify defense depth, 5) Test attack vectors.
How do you implement security fuzzing tests?
Fuzzing implementation: 1) Generate test cases, 2) Test input handling, 3) Check error responses, 4) Verify system stability, 5) Test edge cases.
What are strategies for testing security compliance?
Compliance testing: 1) Test regulation requirements, 2) Verify security controls, 3) Check audit capabilities, 4) Test data protection, 5) Verify compliance reporting.
How do you test security incident response?
Incident response testing: 1) Test detection systems, 2) Verify alert mechanisms, 3) Check response procedures, 4) Test recovery processes, 5) Verify incident logging.
What are patterns for testing security monitoring?
Security monitoring tests: 1) Test detection capabilities, 2) Verify alert systems, 3) Check monitoring coverage, 4) Test response time, 5) Verify data collection.
How do you implement security regression testing?
Regression testing: 1) Test security fixes, 2) Verify vulnerability patches, 3) Check security updates, 4) Test system hardening, 5) Verify security baselines.
What are strategies for testing security architecture?
Architecture testing: 1) Test security layers, 2) Verify security boundaries, 3) Check security controls, 4) Test integration points, 5) Verify defense mechanisms.
How do you test security configurations?
Configuration testing: 1) Test security settings, 2) Verify hardening measures, 3) Check default configs, 4) Test config changes, 5) Verify secure defaults.
What are patterns for testing security isolation?
Isolation testing: 1) Test component isolation, 2) Verify resource separation, 3) Check boundary controls, 4) Test isolation bypass, 5) Verify containment.
How do you implement threat modeling tests?
Threat model testing: 1) Test identified threats, 2) Verify mitigation controls, 3) Check attack surfaces, 4) Test security assumptions, 5) Verify protection measures.
How do you integrate Mocha tests into a CI/CD pipeline?
Integration steps include: 1) Configure test scripts in package.json, 2) Set up test environment in CI, 3) Configure test runners, 4) Set up reporting, 5) Handle test failures. Example: npm test script in CI configuration.
What are best practices for running Mocha tests in CI?
Best practices include: 1) Use --reporter for CI-friendly output, 2) Set appropriate timeouts, 3) Configure retry mechanisms, 4) Handle test artifacts, 5) Implement proper error reporting.
How do you handle test environments in CI/CD?
Environment handling: 1) Configure environment variables, 2) Set up test databases, 3) Manage service dependencies, 4) Handle cleanup, 5) Isolate test environments for each build.
What is the role of test reporting in CI/CD?
Test reporting involves: 1) Generate test results, 2) Create coverage reports, 3) Track test trends, 4) Identify failures, 5) Provide build status feedback. Important for build decisions.
How do you handle test failures in CI/CD?
Failure handling: 1) Configure retry mechanisms, 2) Set failure thresholds, 3) Generate detailed reports, 4) Notify relevant teams, 5) Preserve failure artifacts for debugging.
What are strategies for test parallelization in CI?
Parallelization strategies: 1) Split test suites, 2) Use parallel runners, 3) Balance test distribution, 4) Handle resource conflicts, 5) Aggregate test results.
How do you manage test data in CI/CD?
Test data management: 1) Use data fixtures, 2) Implement data seeding, 3) Handle cleanup, 4) Manage test databases, 5) Ensure data isolation between builds.
What is the purpose of test coverage in CI/CD?
Coverage purposes: 1) Verify test completeness, 2) Identify untested code, 3) Set quality gates, 4) Track testing progress, 5) Guide test development.
How do you optimize test execution in CI?
Optimization strategies: 1) Implement caching, 2) Use test parallelization, 3) Optimize resource usage, 4) Minimize setup time, 5) Remove unnecessary tests.
What are common CI/CD pipeline configurations for Mocha?
Common configurations: 1) Install dependencies, 2) Run linting, 3) Execute tests, 4) Generate reports, 5) Deploy on success. Example using GitHub Actions or Jenkins.
How do you implement test automation in CI/CD?
Automation implementation: 1) Configure test triggers, 2) Set up automated runs, 3) Handle results processing, 4) Implement notifications, 5) Manage test schedules.
What are strategies for managing test dependencies in CI?
Dependency management: 1) Cache node_modules, 2) Use lockfiles, 3) Version control dependencies, 4) Handle external services, 5) Manage environment setup.
How do you handle database testing in CI/CD?
Database testing: 1) Use test databases, 2) Manage migrations, 3) Handle data seeding, 4) Implement cleanup, 5) Ensure isolation between tests.
What are patterns for testing deployment processes?
Deployment testing: 1) Test deployment scripts, 2) Verify environment configs, 3) Check service integration, 4) Test rollback procedures, 5) Verify deployment success.
How do you implement continuous testing?
Continuous testing: 1) Automate test execution, 2) Integrate with CI/CD, 3) Implement test selection, 4) Handle test feedback, 5) Manage test frequency.
What are strategies for test stability in CI?
Stability strategies: 1) Handle flaky tests, 2) Implement retries, 3) Manage timeouts, 4) Handle resource cleanup, 5) Ensure test isolation.
How do you manage test artifacts in CI/CD?
Artifact management: 1) Store test results, 2) Handle screenshots/videos, 3) Manage logs, 4) Configure retention policies, 5) Implement artifact cleanup.
What are patterns for testing infrastructure as code?
Infrastructure testing: 1) Test configuration files, 2) Verify resource creation, 3) Check dependencies, 4) Test scaling operations, 5) Verify cleanup procedures.
How do you implement test monitoring in CI/CD?
Test monitoring: 1) Track execution metrics, 2) Monitor resource usage, 3) Alert on failures, 4) Track test trends, 5) Generate performance reports.
What are advanced strategies for CI/CD integration?
Advanced integration: 1) Implement custom plugins, 2) Create deployment pipelines, 3) Automate environment management, 4) Handle complex workflows, 5) Implement recovery procedures.
How do you implement advanced test orchestration?
Advanced orchestration: 1) Manage test distribution, 2) Handle complex dependencies, 3) Coordinate multiple services, 4) Implement recovery strategies, 5) Manage test scheduling.
What are patterns for testing microservices deployment?
Microservices deployment: 1) Test service coordination, 2) Verify service discovery, 3) Test scaling operations, 4) Check service health, 5) Verify integration points.
How do you implement deployment verification testing?
Deployment verification: 1) Test deployment success, 2) Verify service functionality, 3) Check configuration changes, 4) Test rollback procedures, 5) Verify system health.
What are strategies for testing blue-green deployments?
Blue-green testing: 1) Test environment switching, 2) Verify traffic routing, 3) Check state persistence, 4) Test rollback scenarios, 5) Verify zero downtime.
How do you implement canary testing?
Canary testing: 1) Test gradual rollout, 2) Monitor service health, 3) Verify performance metrics, 4) Handle rollback triggers, 5) Test traffic distribution.
What are patterns for testing service mesh deployments?
Service mesh testing: 1) Test routing rules, 2) Verify traffic policies, 3) Check security policies, 4) Test observability, 5) Verify mesh configuration.
How do you implement chaos testing in CI/CD?
Chaos testing: 1) Test failure scenarios, 2) Verify system resilience, 3) Check recovery procedures, 4) Test degraded operations, 5) Verify system stability.
What are strategies for testing configuration management?
Configuration testing: 1) Test config changes, 2) Verify environment configs, 3) Check secret management, 4) Test config validation, 5) Verify config deployment.
What are the built-in reporters in Mocha?
Built-in reporters include: 1) spec - hierarchical view, 2) dot - minimal dots output, 3) nyan - fun nyan cat reporter, 4) tap - TAP output, 5) json - JSON format, 6) list - simple list, 7) min - minimalistic output.
How do you configure reporters in Mocha?
Reporter configuration: 1) Use --reporter flag in CLI, 2) Configure in mocha.opts, 3) Set in package.json, 4) Specify reporter options, 5) Enable multiple reporters. Example: mocha --reporter spec
What is the spec reporter and when should it be used?
Spec reporter: 1) Provides hierarchical view, 2) Shows nested describe blocks, 3) Indicates test status, 4) Displays execution time, 5) Best for development and debugging. Default reporter for readability.
How do you handle test failure output?
Failure output handling: 1) Display error messages, 2) Show stack traces, 3) Format error details, 4) Include test context, 5) Highlight failure location. Important for debugging.
What is the purpose of the JSON reporter?
JSON reporter: 1) Machine-readable output, 2) CI/CD integration, 3) Custom processing, 4) Report generation, 5) Data analysis. Useful for automated processing.
How do you customize test output format?
Output customization: 1) Select appropriate reporter, 2) Configure reporter options, 3) Set output colors, 4) Format error messages, 5) Control detail level.
What is the TAP reporter used for?
TAP reporter: 1) Test Anything Protocol format, 2) Integration with TAP consumers, 3) Standard test output, 4) Tool compatibility, 5) Pipeline integration. Used for tool interoperability.
How do you enable multiple reporters?
Multiple reporters: 1) Use reporter packages, 2) Configure output paths, 3) Specify reporter options, 4) Handle different formats, 5) Manage output files. Useful for different needs.
What is the purpose of reporter options?
Reporter options: 1) Customize output format, 2) Set output file paths, 3) Configure colors, 4) Control detail level, 5) Set specific behaviors. Enables reporter customization.
How do you handle test duration reporting?
Duration reporting: 1) Configure time display, 2) Set slow test threshold, 3) Show execution times, 4) Highlight slow tests, 5) Track test performance. Important for optimization.
What are patterns for custom reporter implementation?
Custom reporter patterns: 1) Extend Base reporter, 2) Implement event handlers, 3) Format output, 4) Handle test states, 5) Manage reporting lifecycle. Creates specialized reporting.
How do you implement HTML reporting?
HTML reporting: 1) Use mochawesome reporter, 2) Configure report options, 3) Style reports, 4) Include test details, 5) Generate interactive reports. Creates visual reports.
What are strategies for test analytics reporting?
Analytics reporting: 1) Collect test metrics, 2) Generate statistics, 3) Track trends, 4) Create visualizations, 5) Monitor performance. Important for test insights.
How do you handle reporting for parallel tests?
Parallel reporting: 1) Aggregate results, 2) Handle concurrent output, 3) Synchronize reporting, 4) Manage file output, 5) Combine test results. Important for parallel execution.
What are patterns for error reporting?
Error reporting patterns: 1) Format error messages, 2) Include context, 3) Stack trace handling, 4) Group related errors, 5) Error categorization. Improves debugging.
How do you implement coverage reporting?
Coverage reporting: 1) Configure coverage tools, 2) Generate reports, 3) Set thresholds, 4) Track coverage metrics, 5) Monitor trends. Important for test quality.
What are strategies for CI/CD reporting?
CI/CD reporting: 1) Machine-readable output, 2) Build integration, 3) Artifact generation, 4) Status reporting, 5) Pipeline feedback. Essential for automation.
How do you handle test metadata reporting?
Metadata reporting: 1) Collect test info, 2) Track custom data, 3) Include environment details, 4) Report test context, 5) Handle custom fields. Enhances test information.
What are patterns for real-time reporting?
Real-time reporting: 1) Stream test results, 2) Live updates, 3) Progress indication, 4) Status notifications, 5) Immediate feedback. Important for monitoring.
How do you implement performance reporting?
Performance reporting: 1) Track execution times, 2) Monitor resources, 3) Report bottlenecks, 4) Generate trends, 5) Analyze metrics. Important for optimization.
What are advanced patterns for custom reporters?
Advanced reporter patterns: 1) Complex event handling, 2) Custom formatters, 3) Integration features, 4) Advanced analytics, 5) Custom protocols. Creates specialized solutions.
How do you implement distributed reporting?
Distributed reporting: 1) Aggregate results, 2) Synchronize data, 3) Handle partial results, 4) Manage consistency, 5) Report consolidation. Important for distributed testing.
What are strategies for monitoring integration?
Monitoring integration: 1) Metrics export, 2) Alert integration, 3) Dashboard creation, 4) Trend analysis, 5) System monitoring. Important for observability.
How do you implement compliance reporting?
Compliance reporting: 1) Audit trails, 2) Required formats, 3) Policy verification, 4) Evidence collection, 5) Regulatory requirements. Important for regulations.
What are patterns for custom analytics platforms?
Analytics platforms: 1) Data collection, 2) Custom metrics, 3) Analysis tools, 4) Visualization creation, 5) Insight generation. Creates comprehensive analytics.
How do you implement security reporting?
Security reporting: 1) Vulnerability tracking, 2) Security metrics, 3) Compliance checks, 4) Risk assessment, 5) Security monitoring. Important for security.
What are strategies for custom visualization?
Visualization strategies: 1) Custom charts, 2) Interactive reports, 3) Data exploration, 4) Trend visualization, 5) Performance graphs. Enhances understanding.
How do you implement advanced error analysis?
Error analysis: 1) Pattern detection, 2) Root cause analysis, 3) Error correlation, 4) Impact assessment, 5) Resolution tracking. Improves debugging.
What are patterns for custom dashboards?
Dashboard patterns: 1) Custom metrics, 2) Real-time updates, 3) Interactive features, 4) Data visualization, 5) Status monitoring. Creates comprehensive views.
What is performance testing in Mocha and why is it important?
Performance testing involves: 1) Measuring test execution speed, 2) Monitoring resource usage, 3) Identifying bottlenecks, 4) Optimizing test runs, 5) Tracking performance metrics. Important for maintaining efficient test suites.
How do you measure test execution time in Mocha?
Execution time measurement: 1) Use built-in reporters, 2) Implement custom timing, 3) Track individual test durations, 4) Monitor suite execution, 5) Use performance APIs. Example: console.time() or process.hrtime().
What are common performance bottlenecks in Mocha tests?
Common bottlenecks: 1) Slow test setup/teardown, 2) Inefficient assertions, 3) Synchronous operations, 4) Resource leaks, 5) Poor test isolation. Understanding helps optimization.
How do you identify slow tests?
Slow test identification: 1) Use --slow flag, 2) Monitor execution times, 3) Implement timing reporters, 4) Track test duration, 5) Profile test execution. Example: mocha --slow 75.
What is the impact of hooks on test performance?
Hook impact: 1) Setup/teardown overhead, 2) Resource allocation, 3) Asynchronous operations, 4) Database operations, 5) File system access. Optimize hooks for better performance.
How do you optimize test setup and teardown?
Setup/teardown optimization: 1) Minimize operations, 2) Use efficient methods, 3) Share setup when possible, 4) Implement proper cleanup, 5) Cache resources. Reduces overhead.
What role does async/await play in performance?
Async/await impact: 1) Efficient async handling, 2) Reduced callback complexity, 3) Better error handling, 4) Improved readability, 5) Sequential execution control. Important for async operations.
How do you handle memory usage in tests?
Memory management: 1) Monitor memory usage, 2) Clean up resources, 3) Prevent memory leaks, 4) Optimize object creation, 5) Handle large datasets. Important for stability.
What are strategies for test parallelization?
Parallelization strategies: 1) Use multiple processes, 2) Split test suites, 3) Balance test distribution, 4) Handle shared resources, 5) Manage concurrency. Improves execution speed.
How do you monitor test performance?
Performance monitoring: 1) Track execution metrics, 2) Use profiling tools, 3) Monitor resource usage, 4) Collect timing data, 5) Analyze bottlenecks. Important for optimization.
What are strategies for optimizing assertion performance?
Assertion optimization: 1) Use efficient matchers, 2) Minimize assertions, 3) Optimize complex checks, 4) Handle async assertions, 5) Implement custom matchers. Improves test speed.
How do you handle database performance in tests?
Database optimization: 1) Use transactions, 2) Implement connection pooling, 3) Optimize queries, 4) Handle cleanup efficiently, 5) Cache database operations. Reduces database overhead.
What are patterns for optimizing file I/O?
I/O optimization: 1) Minimize file operations, 2) Use streams efficiently, 3) Implement caching, 4) Handle cleanup properly, 5) Optimize read/write operations. Reduces I/O overhead.
How do you optimize network operations?
Network optimization: 1) Mock network calls, 2) Cache responses, 3) Minimize requests, 4) Handle timeouts efficiently, 5) Implement request pooling. Reduces network overhead.
What are strategies for resource management?
Resource management: 1) Proper allocation, 2) Efficient cleanup, 3) Resource pooling, 4) Cache utilization, 5) Memory optimization. Important for test efficiency.
How do you implement performance benchmarks?
Benchmark implementation: 1) Define metrics, 2) Create baseline tests, 3) Measure performance, 4) Compare results, 5) Track trends. Important for monitoring improvements.
What are patterns for testing concurrent operations?
Concurrency testing: 1) Handle parallel execution, 2) Test race conditions, 3) Manage shared resources, 4) Verify thread safety, 5) Test synchronization. Important for parallel code.
How do you optimize test data management?
Data optimization: 1) Efficient data creation, 2) Data reuse strategies, 3) Cleanup optimization, 4) Data caching, 5) Memory-efficient structures. Reduces data overhead.
What are strategies for cache optimization?
Cache optimization: 1) Implement caching layers, 2) Optimize cache hits, 3) Handle cache invalidation, 4) Manage cache size, 5) Monitor cache performance. Improves test speed.
How do you handle performance profiling?
Performance profiling: 1) Use profiling tools, 2) Analyze bottlenecks, 3) Monitor resource usage, 4) Track execution paths, 5) Identify optimization opportunities. Guides improvements.
What are advanced performance testing patterns?
Advanced patterns: 1) Complex benchmarking, 2) Distributed testing, 3) Load simulation, 4) Performance analysis, 5) Advanced metrics. Enables comprehensive testing.
How do you implement distributed performance testing?
Distributed testing: 1) Coordinate test execution, 2) Aggregate results, 3) Handle network latency, 4) Manage resources, 5) Monitor system performance. Tests scalability.
What are strategies for testing system limits?
Limit testing: 1) Test resource boundaries, 2) Verify system capacity, 3) Check performance degradation, 4) Monitor system stability, 5) Test recovery behavior. Tests system limits.
How do you implement load testing?
Load testing: 1) Simulate user load, 2) Monitor system response, 3) Test scalability, 4) Measure performance impact, 5) Analyze system behavior. Tests under load.
What are patterns for stress testing?
Stress testing: 1) Push system limits, 2) Test failure modes, 3) Verify recovery, 4) Monitor resource exhaustion, 5) Test system stability. Tests system resilience.
How do you implement endurance testing?
Endurance testing: 1) Long-running tests, 2) Monitor resource usage, 3) Check memory leaks, 4) Verify system stability, 5) Test sustained performance. Tests long-term behavior.
What are strategies for spike testing?
Spike testing: 1) Test sudden load increases, 2) Verify system response, 3) Check recovery time, 4) Monitor resource usage, 5) Test system stability. Tests burst handling.
How do you implement scalability testing?
Scalability testing: 1) Test system scaling, 2) Verify performance consistency, 3) Check resource utilization, 4) Monitor bottlenecks, 5) Test scaling limits. Tests growth capacity.
What are patterns for volume testing?
Volume testing: 1) Test data volume handling, 2) Verify system performance, 3) Check storage capacity, 4) Monitor processing speed, 5) Test data limits. Tests data handling.
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