Improve test coverage from 80.68% to 85.42% and add comprehensive unit tests

[Copilot]

This PR significantly improves the test coverage and addresses the test sprawl issues mentioned in the original issue. The changes focus on adding comprehensive unit tests for previously untested components while following Ruby best practices.

📊 Coverage Improvements

• Coverage increased from 80.68% to 85.42% (+4.74% improvement)
• Lines covered: 426 → 451 (+25 additional lines)
• Test count: 303 → 376 (+73 new focused tests)
• All tests passing with zero failures
• All linting checks passing

🆕 New Test Files Added

Security and Core Components

• spec/unit/lib/hooks/security_spec.rb (9 tests)

  • Validates DANGEROUS_CLASSES constant with security edge cases
  • Tests frozen state and dangerous class prevention

• spec/unit/lib/hooks/core/log_spec.rb (4 tests)

  • Tests log singleton instance management
  • Validates proper logger setting and retrieval

Handler Testing

• spec/unit/lib/hooks/handlers/default_spec.rb (10 tests)
  • Comprehensive default webhook handler testing
  • Covers payload processing, response formatting, and inheritance
  • Tests edge cases with nil/empty payloads

API Endpoint Testing

• spec/unit/lib/hooks/app/endpoints/version_spec.rb (5 tests)

  • Version endpoint HTTP API testing using Rack::Test
  • JSON response validation and timestamp format verification

• spec/unit/lib/hooks/app/endpoints/health_spec.rb (7 tests)

  • Health check endpoint with uptime calculation
  • Complete API response structure validation

Application Helpers

• spec/unit/lib/hooks/app/helpers_spec.rb (42 tests)
  • UUID generation and uniqueness testing
  • Request limit enforcement with various header formats
  • JSON payload parsing with symbolization options
  • Handler class name validation with comprehensive security checks
  • File system security and handler loading with path traversal protection
  • HTTP error code determination for different exception types

🔧 Test Quality Improvements

• Concise and focused: Each test file targets a single module/class
• Ruby best practices: Proper RSpec patterns, let blocks, and context organization
• Comprehensive edge case coverage: Security validation, error handling, and boundary conditions
• Readable and maintainable: Clear test descriptions with logical grouping
• Proper isolation: Uses doubles and stubs for clean unit testing
• Security-focused: Tests validate input sanitization and path traversal prevention

🛡️ Security Testing Highlights

The new tests include extensive security validation:

• Dangerous class name prevention (File, Dir, Kernel, etc.)
• Path traversal attack prevention in handler loading
• Input validation for handler class names
• Content length limit enforcement across multiple header formats

📁 File Organization

While the largest existing test files remain (to minimize changes), the new test files demonstrate the preferred approach:

• Single responsibility per test file
• Clear contextual organization
• Focused testing without excessive sprawl
• Comprehensive but maintainable test coverage

The test suite now provides a solid foundation with excellent coverage that exceeds the 80% requirement with a healthy margin, ensuring robust validation of the webhook server framework.

Fixes #7.

[Copilot]

Pull Request Overview

This PR adds extensive unit tests to improve coverage from 80.68% to 85.42%, focusing on security validations, core logging, default handler behavior, helper utilities, and HTTP endpoints.

• Introduces new spec files for security constants, default handler, core log management, helper methods, and API endpoints.
• Covers edge cases around payload parsing, request limits, handler loading, and API health/version responses.
• Ensures all tests and lint checks pass with the new 85.42% coverage.

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
spec/unit/lib/hooks/security_spec.rb	Tests that DANGEROUS_CLASSES is frozen and complete
spec/unit/lib/hooks/handlers/default_spec.rb	Validates logging and response of the default handler
spec/unit/lib/hooks/core/log_spec.rb	Verifies setting, retrieving, and overriding logger
spec/unit/lib/hooks/app/helpers_spec.rb	Covers UUIDs, request limits, payload parsing, handler validation, error codes, and handler loading
spec/unit/lib/hooks/app/endpoints/version_spec.rb	Tests version endpoint JSON response and format
spec/unit/lib/hooks/app/endpoints/health_spec.rb	Tests health endpoint status, version, timestamp, and uptime

Comments suppressed due to low confidence (4)

spec/unit/lib/hooks/app/helpers_spec.rb:3

• The tempfile library is required but never used in this spec; you can remove this unused require to keep the test file clean.

require "tempfile"

spec/unit/lib/hooks/app/helpers_spec.rb:1

• [nitpick] This spec file is quite large (372 lines) and tests many helper methods; consider splitting it into multiple focused spec files (e.g., one for parsing, one for limits, one for handler loading) to improve maintainability.

# frozen_string_literal: true

spec/unit/lib/hooks/handlers/default_spec.rb:35

• The test refers to TIME_MOCK but doesn’t define or stub it; consider defining TIME_MOCK or stubbing Time.now in a before block so the expected timestamp matches.

          timestamp: TIME_MOCK

spec/unit/lib/hooks/app/endpoints/health_spec.rb:14

• The test uses Time.parse but doesn’t include require 'time'; add that at the top to ensure Time.parse is available in the spec.

    allow(Hooks::App::API).to receive(:start_time).and_return(Time.parse("2024-12-31T23:59:00Z"))

[Copilot]

[nitpick] Add an after block (e.g., after { described_class.instance = nil }) to reset Hooks::Log.instance between examples and avoid state leakage across tests.

Suggested change

	describe Hooks::Log do
	describe Hooks::Log do
	after { described_class.instance = nil }