Test Runner Skill

Purpose

Intelligently run tests with smart detection of changed files to provide faster feedback during development.

What This Skill Does

Provides multiple test execution modes:

•Smart Mode - Run only tests affected by recent changes
•Full Mode - Run complete test suite (625+ tests)
•Coverage Mode - Run tests with coverage reporting
•Watch Mode - Run tests in watch mode for active development
•Failed Only - Re-run only previously failed tests

Execution Modes

Mode 1: Smart Test Execution (Default)

Detect changed files and run related tests only:

bash

# Get changed files since last commit
git diff --name-only HEAD

# For each changed file, find related test files
# Example: src/services/medications.ts → medications.test.ts

Smart Detection Rules:

•src/services/X.ts → src/services/__tests__/X.test.ts
•src/components/X.tsx → src/components/__tests__/X.test.tsx
•src/api/X.ts → src/api/__tests__/X.test.ts
•src/utils/X.ts → src/utils/__tests__/X.test.ts

Execution:

bash

npm test -- path/to/test1.test.ts path/to/test2.test.ts

Mode 2: Full Test Suite

Run all tests (use for pre-commit or CI/CD):

bash

npm test

Expected baseline: 625+ tests passing

Mode 3: Coverage Mode

Run tests with coverage report:

bash

npm test -- --coverage --watchAll=false

Coverage targets:

•Statements: >80%
•Branches: >75%
•Functions: >80%
•Lines: >80%

Mode 4: Watch Mode

Run tests in watch mode for active development:

bash

npm test -- --watch

Useful when actively developing a feature.

Mode 5: Failed Only

Re-run only failed tests from previous run:

bash

npm test -- --onlyFailures

Smart Mode Algorithm

code

1. Get list of changed files (git diff)
2. For each changed file:
   a. Identify test file pattern
   b. Check if test file exists
   c. Add to test queue
3. Also include:
   - Integration tests if multiple services changed
   - E2E tests if UI components changed
4. Run collected tests
5. Report results with delta from baseline

Output Format

Smart Mode Output

code

🧪 SMART TEST RUNNER
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Detecting changed files...
✓ Found 3 changed files

Changed Files:
  src/services/medications.ts
  src/components/PatientProfile.tsx
  src/utils/phiEncryption.ts

Related Tests:
  src/services/__tests__/medications.test.ts (47 tests)
  src/components/__tests__/PatientProfile.test.tsx (23 tests)
  src/utils/__tests__/phiEncryption.test.ts (15 tests)

Running 85 tests across 3 test suites...

Test Suites: 3 passed, 3 total
Tests:       85 passed, 85 total
Snapshots:   0 total
Time:        4.231 s

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✅ ALL TESTS PASSED (85/85)
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Time saved: ~45s (vs. full suite)

Full Mode Output

code

🧪 FULL TEST SUITE
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Running complete test suite...

Test Suites: 124 passed, 124 total
Tests:       627 passed, 2 skipped, 629 total
Snapshots:   0 total
Time:        52.847 s

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
✅ ALL TESTS PASSED (627/629)
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Test Count Delta: +2 (baseline: 625)
Skipped: 2 tests (.skip)

Coverage Mode Output

code

🧪 TEST COVERAGE REPORT
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Running tests with coverage...

Test Suites: 124 passed, 124 total
Tests:       627 passed, 627 total

Coverage Summary:
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
File        % Stmts  % Branch  % Funcs  % Lines  Uncovered
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
All files     87.23    82.15    89.47    87.19
services/     91.45    85.32    93.21    91.38
utils/        89.12    80.45    88.76    89.04
components/   84.67    79.23    86.34    84.59
api/          88.91    83.67    90.12    88.87
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

✅ Coverage targets met (>80% all categories)

Detailed report: coverage/lcov-report/index.html

Failure Output Format

code

🧪 SMART TEST RUNNER
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Detecting changed files...
✓ Found 2 changed files

Running 43 tests across 2 test suites...

Test Suites: 1 failed, 1 passed, 2 total
Tests:       2 failed, 41 passed, 43 total

FAIL src/services/__tests__/medications.test.ts
  ● MedicationService › should create medication

    expect(received).toHaveBeenCalledWith(
      expect.objectContaining({
        name: "Aspirin",
        dosage: "100mg"
      })
    )

    Expected: objectContaining({"dosage": "100mg", "name": "Aspirin"})
    Received: {"dosage": "81mg", "name": "Aspirin", "frequency": "daily"}

      145 |   await service.createMedication(mockData);
      146 |
    > 147 |   expect(supabase.from).toHaveBeenCalledWith(
          |                        ^
      148 |     expect.objectContaining({
      149 |       name: "Aspirin",
      150 |       dosage: "100mg"

    at Object.<anonymous> (src/services/__tests__/medications.test.ts:147:24)

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
❌ TESTS FAILED (2/43)
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

Failed Tests:
  ✗ MedicationService › should create medication
  ✗ MedicationService › should validate dosage format

Fix these tests before committing.

When to Use This Skill

Smart Mode (Default):

•During active development
•After making small changes
•Quick feedback loop

Full Mode:

•Before commits
•Before creating PRs
•Before deployments
•In CI/CD pipeline

Coverage Mode:

•Before releases
•After adding new features
•During code reviews

Watch Mode:

•While writing tests (TDD)
•Active feature development

Failed Only:

•After fixing failed tests
•Quick validation of fixes

Performance Optimization

Baseline Performance:

•Full suite: ~50-60 seconds (625+ tests)
•Smart mode: ~4-10 seconds (20-100 tests)
•Single file: ~1-3 seconds

Speed Improvement:

•Smart mode: 85-92% faster than full suite
•Failed only: 95% faster (when few failures)

Integration with Pre-Commit

This skill integrates with the pre-commit skill:

•Pre-commit runs full test suite
•Development uses smart mode
•CI/CD uses full mode + coverage

Notes for AI Agent

•Default to smart mode unless user requests full mode
•Show test count delta vs. baseline (625 tests)
•Report skipped tests (*.skip files)
•If smart mode finds 0 tests, suggest running full suite
•Track test execution time
•Highlight any new test failures
•Suggest running coverage mode if coverage drops
•Don't automatically fix test failures - report them