test: Add comprehensive test coverage for all hooks

Overview

Extend the bats testing framework to provide comprehensive test coverage for all 26 hook scripts.

Current State

• Testing framework established with bats
• Sample tests created for:
  • hooks/commits/gitlint.sh
  • hooks/nix/nix-fmt.sh
• Test helper utilities available
• CI integration configured

Requirements

Test Coverage Goals

• 100% of hooks have at least basic tests
• 80%+ code coverage across all hooks
• Edge cases and error conditions tested
• Multi-platform compatibility verified

Hooks Needing Tests

Commits

• commitizen.sh
• commitlint.sh
• gitlint.sh ✅

Nix

• attestation.nix
• nix-build-check.sh
• nix-build.sh
• nix-darwin-check.sh
• nix-flake-check.sh
• nix-fmt.sh ✅
• nix-home-manager-check.sh
• nix-lint.sh
• publish-to-nixpkgs.sh

CI

• github.sh
• gitlint.sh

Configs

• yamlfmt.sh

Terraform

• pluralith.sh
• tfupdate.sh

Web

• css/csslint.sh
• js/eslint.sh
• js/fixmyjs.sh
• js/jshint.sh
• scss/scss-lint.sh

Other

• backup-nixos.sh
• update-vm.sh
• witness.sh
• pluralith.sh (root)

Test Structure

Each test file should include:

1. Existence and executability check
2. Missing dependency handling
3. Success case validation
4. Failure case validation
5. Edge case handling (empty input, malformed data, etc.)

Deliverables

• Complete test suite for all hooks
• Test documentation updates
• CI passing with all tests
• Coverage report generation
• Performance benchmarks

Success Criteria

• All hooks have corresponding test files
• Tests run successfully on Ubuntu and macOS
• Code coverage >80%
• All tests pass in CI
• Clear documentation for adding new tests

Related

• #26 - CI/CD pipeline implementation
• #22 - Nix hooks test suite