test: CLI test suite health summary and improvement roadmap

[jongio]

Summary

The Go CLI test suite scores well overall (all source files have corresponding tests, good table-driven patterns, proper error path coverage), but several structural improvements would increase confidence and maintainability.

Findings

Coverage Score: Good (7.5/10)

Strengths:

• 100% source file coverage — every .go file has at least one test file
• Extensive table-driven tests with 8-15+ cases per function
• Error paths well-tested (ValidationError, ScriptNotFoundError, InvalidShellError, ExecutionError)
• Platform-specific tests properly gated with t.Skip()
• No TODO/FIXME debt in test files
• Good dependency injection for mocking (fakeExecutor, mock resolver)
• Integration tests properly separated with build tags

Areas for Improvement:

Area	Severity	Details
Web E2E tests not in CI	High	8 Playwright specs exist but are never run in CI
MCP server init untested	Medium	runMCPServer() has ~75 lines with no direct tests
Path traversal edge cases	Medium	Security-critical path validation lacks adversarial inputs
Boundary condition gaps	Low	Nil inputs, empty structs, special chars untested
Interactive stdin untested	Low	Stdin pipe attachment (executor.go:170) has no automated test

Test Infrastructure

• Go tests: Well-structured with unit + integration separation
• Playwright tests: Fully configured but not integrated into CI
• No flaky tests detected: No sleep calls, proper skip annotations
• Mocking: Uses dependency injection rather than monkey-patching

Related Issues Filed

Individual issues have been filed for the top findings above. See issues with the test-health label for details.