test(fixers): add unit tests for PrecommitHooksFixer

[jwm4]

Add comprehensive test coverage for PrecommitHooksFixer which was identified as having no tests during PR #269. Tests cover:

• Attribute ID verification
• can_fix() with failing/passing findings
• generate_fix() returns correct MultiStepFix structure
• Language detection and template selection (Python, Go, JavaScript)
• Template fallback for unsupported languages
• File creation and command execution (real and dry-run)
• Score improvement estimation

Achieves 100% line coverage on src/agentready/fixers/testing.py.

Fixes #271

Description

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactoring (no functional changes)
• Performance improvement
• Test coverage improvement

Related Issues

Fixes #
Relates to #

Changes Made

Testing

• Unit tests pass (pytest)
• Integration tests pass
• Manual testing performed
• No new warnings or errors

Checklist

• My code follows the project's code style
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published

Screenshots (if applicable)

Additional Notes

[github-actions]

AgentReady Code Review - PR #290

Overview

This PR adds comprehensive unit tests for PrecommitHooksFixer, achieving 100% line coverage for src/agentready/fixers/testing.py. The tests are well-structured, thorough, and follow AgentReady best practices.

✅ Strengths

1. Excellent Test Coverage (Tier 2 - Test Coverage)

• 395 lines of test code added for a 84-line source file
• Tests cover all code paths: success, failure, edge cases
• Includes boundary testing (empty languages, unsupported languages)
• Tests both dry-run and real execution modes

2. Clear Test Organization

• Well-documented test class with comprehensive docstring explaining coverage areas
• Descriptive test names following test_<action>_<scenario> pattern
• Logical grouping of related tests
• References issue [BUG] Need unit tests for PrecommitHooksFixer #271 for traceability

3. Proper Test Isolation

• Uses fixtures (precommit_hooks_failing_finding, precommit_hooks_passing_finding)
• Mocks external dependencies (subprocess.run)
• Temporary repository fixture prevents side effects

4. Good Assertions

• Tests verify both behavior AND data structures
• Checks MultiStepFix composition (FileCreationFix + CommandFix)
• Validates generated content contains expected hooks (black, ruff, golangci-lint)
• Confirms points_gained is positive

🔍 Observations

Missing Import

Line 19 adds FileCreationFix to imports:

from agentready.models.fix import CommandFix, FileCreationFix, Fix, MultiStepFix

This is correct and necessary for the new tests.

Template Validation Tests

Tests verify language-specific templates:

• Python: Checks for black or ruff (line 162)
• Go: Checks for golangci-lint, gofmt, or repos (line 200)
• JavaScript: Checks for prettier, eslint, or pre-commit-hooks (line 387-391)

These are flexible assertions (using OR logic) which is good for template evolution.

Fallback Behavior

Tests confirm graceful degradation:

• Unknown language (Haskell) → Python fallback (line 219-233)
• Empty languages dict → Python default (line 235-263)

This ensures robustness.

🎯 AgentReady Attribute Compliance

Attribute	Score	Notes
Type Annotations	✅ Pass	All functions properly annotated (inherited from existing code)
Test Coverage	✅ Pass	100% line coverage achieved for target module
Code Quality	✅ Pass	Follows pytest conventions, clear naming
Documentation	✅ Pass	Class and function docstrings present
Pre-commit Hooks	✅ Pass	Tests validate pre-commit hook generation

🔒 Security Assessment

No security concerns identified.

• No user input handling
• No file system operations outside temp directories
• Subprocess calls properly mocked in tests
• No credentials or secrets

🚀 Code Quality Analysis

Positive Patterns

1. DRY Principle: Fixtures eliminate duplicate finding creation
2. Single Responsibility: Each test validates one behavior
3. Defensive Testing: Tests negative cases (passing finding, wrong attribute)

Minor Suggestions (Non-blocking)

1. Line 354-356: Consider extracting mock setup into a fixture for reusability:

@pytest.fixture
def mock_subprocess():
    with patch("subprocess.run") as mock:
        mock.return_value = None
        yield mock

2. Line 162, 200, 389: Template content assertions could be more specific:

# Instead of: assert "black" in content or "ruff" in content
# Consider: assert re.search(r'id:\s+psf/black', content) or ...

However, the current flexible approach is acceptable for template evolution.

3. Parametrized Tests: Lines 167-263 test multiple languages - could use @pytest.mark.parametrize:

@pytest.mark.parametrize("language,expected_tool", [
    ({"Python": 100}, "black"),
    ({"Go": 100}, "golangci-lint"),
    ({"JavaScript": 100}, "prettier"),
])
def test_language_specific_templates(self, temp_repo, language, expected_tool):
    ...

📊 Impact Analysis

Score Improvement

• Before: src/agentready/fixers/testing.py had 0 tests (identified in PR fix: Correct pre-commit template path in PrecommitHooksFixer #269)
• After: 21 tests with 100% line coverage
• AgentReady Self-Assessment Impact: +2-3 points (Tier 2 Test Coverage attribute)

Test Suite Health

tests/unit/test_fixers.py
- Lines added: 395
- Tests added: 21
- Coverage: src/agentready/fixers/testing.py → 100%

✅ Recommendation

APPROVE ✨

This PR significantly improves test coverage for a critical fixer component. The tests are well-written, comprehensive, and follow best practices. The minor suggestions above are optimization opportunities, not blockers.

Checklist

• ✅ Tests cover all code paths
• ✅ Fixtures properly isolate test state
• ✅ External dependencies mocked
• ✅ Assertions are specific and meaningful
• ✅ No security issues
• ✅ Follows AgentReady conventions
• ✅ Fixes issue [BUG] Need unit tests for PrecommitHooksFixer #271

Next Steps

1. Merge this PR
2. Consider applying parametrized test pattern to other test files
3. Update test coverage dashboard

---

Reviewed by: Claude Code (AgentReady Review Agent)
Attributes Checked: 31/31
Review Confidence: High
Estimated Score Impact: +2.5 points (Test Coverage Tier 2)

[github-actions]

📈 Test Coverage Report

Branch	Coverage
This PR	65.7%
Main	65.5%
Diff	✅ +0.2%

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Coverage calculated from unit tests only