Unit Test Loop - Coverage Improvement Skill

Unit Test Loop - Coverage Improvement

Current branch: !git branch --show-current 2>/dev/null || echo "not in git repo"

The unit test loop uses a 2-phase workflow with Dex task tracking for persistent, cross-session test coverage improvement.

The 2-Phase Approach

| Phase | Name | Purpose | |-------|------|---------| | 1 | Coverage Analysis | Identify gaps, prioritize files | | 2 | Dex Handoff | Create epic + tasks from analysis |

After Phase 2, use /complete <task-id> for each test task.

Starting the Loop

/ut "Improve coverage for auth module"            # Basic
/ut "Add tests" --target 80%                      # With target

Phase 1: Coverage Analysis

Run coverage command to see current state
Identify files with low coverage
Prioritize 3-7 test tasks for user-facing behavior

Output: <phase_complete phase="1"/>

Phase 2: Dex Handoff

Create Dex epic with target, then tasks for each gap:

# Create epic
dex create "Unit Test Coverage" --description "Target: 80% coverage"

# For each gap
dex create "Test: login validation" --parent <epic-id> --description "
File: src/auth/login.ts
Current: 45%

Test should verify:
- [ ] Valid credentials succeed
- [ ] Invalid credentials show error
"

Output: <phase_complete phase="2"/> or <promise>UT SETUP COMPLETE</promise>

Working on Tasks

Use Dex + /complete workflow:

dex list --pending      # See what's ready
dex start <id>          # Start working
/complete <id>          # Run reviewers and complete

React Testing Library Patterns

"The more your tests resemble the way your software is used, the more confidence they can give you."

Query Priority (Use in Order)

| Priority | Query | Use Case | |----------|-------|----------| | 1 | getByRole | Default choice, use name option | | 2 | getByLabelText | Form fields with labels | | 3 | getByPlaceholderText | Only if no label available | | 4 | getByText | Non-interactive elements | | 5 | getByTestId | Last resort only |

Query Types

| Type | When to Use | |------|-------------| | getBy/getAllBy | Element exists (throws if not found) | | queryBy/queryAllBy | Only for asserting absence | | findBy/findAllBy | Async elements (returns Promise) |

Best Practices

// Use screen
screen.getByRole('button', { name: /submit/i })

// Use userEvent.setup()
const user = userEvent.setup()
await user.click(button)

// Use jest-dom matchers
expect(button).toBeDisabled()  // Not: expect(button.disabled).toBe(true)

// Avoid act() - RTL handles it
await screen.findByText('Loaded')  // Not: act(() => ...)

Quality Standards

ONE test per task - Focused, reviewable commits
User-facing behavior only - Test what users depend on
Quality over quantity - One great test beats ten shallow ones
No coverage gaming - Use /* v8 ignore */ for untestable code

Command Reference

/ut "prompt"                  # Start analysis
/ut "prompt" --target 80%     # With target
/cancel-ut                    # Cancel loop
/complete <task-id>           # Complete task with reviewers

/complete - Run reviewers and mark Dex task complete
dex list - View pending tasks
dex-workflow skill - Full Dex usage patterns

Agent Skills: Unit Test Loop - Coverage Improvement

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