name: Testing Standards description: This skill should be used when the user asks about "testing", "test coverage", "unit tests", "integration tests", "test organization", "test best practices", "flaky tests", "test isolation", "TDD", "regression tests", or needs guidance on test structure, coverage requirements, and test execution. version: 1.0.0

Testing Standards

Guidance for implementing comprehensive testing that meets SDLC requirements.

Tooling

Available Tools: If using Claude Code, the pr-review-toolkit:pr-test-analyzer agent reviews test coverage and identifies gaps. Use after creating PRs to ensure adequate test coverage.

Test Organization

Required Test Categories (MUST)

Projects MUST maintain these test categories:

Naming Convention (MUST)

Test files MUST be clearly identifiable by naming convention:

Test Coverage

Coverage Requirements

Regression Tests (MUST)

Bug fixes MUST include regression tests that:

1. Fail before the fix is applied
2. Pass after the fix is applied
3. Document the bug being fixed

#[test]
fn test_issue_123_null_pointer_on_empty_input() {
    // Regression test for issue #123
    // Previously caused null pointer when input was empty
    let result = process_input("");
    assert!(result.is_ok());
}

Critical Path Coverage (MUST)

Critical paths requiring 95%+ coverage:

• Authentication and authorization
• Data validation and sanitization
• Financial calculations
• Security-sensitive operations
• Data persistence operations

Test Execution

Pre-Merge Requirements (MUST)

1. All tests MUST pass before code can be merged
2. Tests MUST be deterministic (no flaky tests)
3. Tests MUST be isolated (no shared state between tests)
4. Tests MUST run on all supported platforms in CI

Performance Guidelines (SHOULD)

Flaky Test Policy

Flaky tests (tests that sometimes pass, sometimes fail) MUST be:

1. Identified and tracked
2. Fixed or quarantined immediately
3. Never ignored or re-run until green

Test Best Practices

Arrange-Act-Assert Pattern (MUST)

Tests MUST follow the AAA pattern:

test("should calculate total with discount", () => {
  // Arrange
  const cart = new ShoppingCart();
  cart.addItem({ price: 100, quantity: 2 });
  const discount = 0.1;

  // Act
  const total = cart.calculateTotal(discount);

  // Assert
  expect(total).toBe(180);
});

Test Naming (MUST)

Test names MUST clearly describe what is being tested:

Good:

test_user_creation_with_valid_email_succeeds
test_login_with_invalid_password_returns_401
test_empty_cart_returns_zero_total

Bad:

test1
testUser
test_it_works

Coverage Requirements (MUST)

Tests MUST cover:

• Happy path: Expected inputs produce expected outputs
• Error cases: Invalid inputs produce appropriate errors
• Edge cases: Boundary conditions handled correctly

Edge Cases to Test

Implementation Checklist

• Organize tests by category (unit, integration, e2e)
• Follow naming conventions for test files
• Set up coverage measurement
• Configure coverage reporting in CI
• Ensure all tests are deterministic
• Verify test isolation
• Add regression tests for bug fixes
• Cover critical paths with 95%+ coverage

Compliance Verification

# Run all tests
make test

# Check coverage
make coverage

# Verify no flaky tests (run multiple times)
for i in {1..5}; do make test || exit 1; done

# Check critical path coverage (language-specific)
coverage report --include="src/auth/*,src/security/*" --fail-under=95

Additional Resources

Reference Files

• references/test-patterns.md - Common test patterns and anti-patterns
• references/coverage-config.md - Coverage tool configuration

Examples

• examples/rust-test-setup.md - Rust test organization
• examples/typescript-jest.config.js - Jest configuration
• examples/python-pytest.ini - Pytest configuration