# Implementation Plan: Test Coverage Improvement

## Overview

This plan focuses on increasing test coverage to a minimum of 95% across all metrics by adding targeted unit tests and property-based tests for uncovered branches in helpers.ts, middlewares, and rbac.ts.

## Tasks

- [ ] 1. Expand helpers.ts test coverage
  - [ ] 1.1 Add tests for supportsColor environment variable scenarios
    - Test FORCE_COLOR environment variable (values: 0, 1, 2, 3)
    - Test NO_COLOR environment variable
    - Test CI environment variable combinations
    - Test when process.stdout is undefined or null
    - _Requirements: 1.2, 1.3, 1.4_
  
  - [ ]* 1.2 Add property test for supportsColor fallback behavior
    - **Property: Environment Detection Consistency**
    - **Validates: Requirements 1.4**
  
  - [ ] 1.3 Add tests for supportsColor error handling
    - Test when accessing process.env throws exception
    - Test when process.stdout.isTTY throws exception
    - Verify fallback returns false in error cases
    - _Requirements: 1.5, 4.1_
  
  - [ ]* 1.4 Add unit tests for edge cases in color detection
    - Test empty string environment variables
    - Test malformed environment variable values
    - _Requirements: 4.1, 4.5_

- [ ] 2. Checkpoint - Verify helpers.ts coverage
  - Run coverage report and ensure helpers.ts reaches ≥95% branch coverage

- [ ] 3. Expand Express middleware test coverage
  - [ ] 3.1 Add tests for custom getRole option
    - Test middleware uses custom getRole function when provided
    - Test middleware falls back to default when getRole not provided
    - _Requirements: 2.2_
  
  - [ ] 3.2 Add tests for custom getParams option
    - Test middleware uses custom getParams function when provided
    - Test middleware falls back to default when getParams not provided
    - _Requirements: 2.3_
  
  - [ ] 3.3 Add tests for custom onDenied callback
    - Test onDenied is called when access is denied
    - Test response is sent correctly through onDenied
    - _Requirements: 2.4_
  
  - [ ] 3.4 Add tests for Express middleware error handling
    - Test that errors from rbac.can() are passed to next(err)
    - Test that errors from custom callbacks are handled
    - _Requirements: 2.5, 4.3_

- [ ] 4. Expand Nest middleware test coverage
  - [ ] 4.1 Add tests for Nest custom options
    - Test custom getRole, getParams, and onDenied in Nest context
    - _Requirements: 2.2, 2.3, 2.4_
  
  - [ ] 4.2 Add tests for Nest middleware error handling
    - Test that errors from rbac.can() are passed to next(err)
    - _Requirements: 2.6, 4.3_

- [ ] 5. Expand Fastify middleware test coverage
  - [ ] 5.1 Add tests for Fastify custom options
    - Test custom getRole, getParams, and onDenied in Fastify context
    - _Requirements: 2.2, 2.3, 2.4_
  
  - [ ] 5.2 Add tests for Fastify middleware error handling
    - Test that errors from rbac.can() are handled appropriately
    - _Requirements: 2.7, 4.3_
  
  - [ ]* 5.3 Add property test for middleware custom options
    - **Property 1: Middleware Custom Options**
    - **Validates: Requirements 2.2, 2.3, 2.4**

- [ ] 6. Checkpoint - Verify middleware coverage
  - Run coverage report and ensure middlewares reach ≥95% branch coverage

- [ ] 7. Expand rbac.ts test coverage
  - [ ] 7.1 Add tests for undefined logger configuration
    - Test RBAC uses defaultLogger when logger is undefined
    - Test logging works correctly with defaultLogger
    - _Requirements: 3.2, 4.5_
  
  - [ ] 7.2 Add tests for disabled logging
    - Test no logging occurs when enableLogger is false
    - Verify logger functions are not called when disabled
    - _Requirements: 3.3_
  
  - [ ]* 7.3 Add property test for logging disabled
    - **Property 2: RBAC Logging Disabled**
    - **Validates: Requirements 3.3**
  
  - [ ] 7.4 Add tests for non-existent roles
    - Test RBAC returns false for non-existent roles
    - Test no errors are thrown for non-existent roles
    - _Requirements: 3.4, 4.1_
  
  - [ ]* 7.5 Add property test for non-existent roles
    - **Property 3: RBAC Non-existent Role**
    - **Validates: Requirements 3.4**
  
  - [ ] 7.6 Add tests for pattern cache
    - Test pattern cache stores results correctly
    - Test pattern cache reuses stored results
    - Test cache behavior with different patterns
    - _Requirements: 3.5, 4.4_
  
  - [ ]* 7.7 Add property test for pattern cache reuse
    - **Property 4: RBAC Pattern Cache Reuse**
    - **Validates: Requirements 3.5**

- [ ] 8. Add edge case tests across all files
  - [ ] 8.1 Add tests for invalid input handling
    - Test null/undefined values passed to functions
    - Test empty strings and arrays
    - Test malformed configuration objects
    - _Requirements: 4.1, 4.5_
  
  - [ ] 8.2 Add tests for async operation failures
    - Test when async operations in when() functions fail
    - Verify proper error handling and fallback behavior
    - _Requirements: 4.3_

- [ ] 9. Final checkpoint - Verify global coverage targets
  - Run full test suite with coverage
  - Verify statements coverage ≥ 95%
  - Verify branches coverage ≥ 95%
  - Verify functions coverage = 100%
  - Verify lines coverage ≥ 95%
  - Review coverage report for any remaining gaps
  - _Requirements: 6.1, 6.2, 6.3, 6.4, 6.5_

## Notes

- Tasks marked with `*` are optional and can be skipped for faster implementation
- Each task references specific requirements for traceability
- Property tests use fast-check library with minimum 100 iterations
- All tests must be written in English
- Focus on uncovered branches identified in coverage report
- Maintain existing test patterns and quality standards