AgentSkillsCN

unit-test-loop

当用户要求“提升测试覆盖率”、“添加单元测试”、“采用 TDD”、“测试此模块”、“为……编写测试”、“提高覆盖率”、“/ut 命令”,或讨论单元测试策略时,应使用此技能。涵盖单元测试循环的工作流程、React Testing Library 的最佳实践、查询优先级,以及提升覆盖率的各类策略。

SKILL.md
--- frontmatter
name: unit-test-loop
description: |
  This skill should be used when the user asks to "improve test coverage",
  "add unit tests", "TDD", "test this module", "write tests for", "increase
  coverage", "/ut command", or discusses unit testing strategies. Covers the
  unit test loop workflow, React Testing Library best practices, query
  priorities, and coverage improvement strategies.
version: 2.0.0

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

PhaseNamePurpose
1Coverage AnalysisIdentify gaps, prioritize files
2Dex HandoffCreate epic + tasks from analysis

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

Starting the Loop

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

Phase 1: Coverage Analysis

  1. Run coverage command to see current state
  2. Identify files with low coverage
  3. 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:

bash
# 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:

bash
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)

PriorityQueryUse Case
1getByRoleDefault choice, use name option
2getByLabelTextForm fields with labels
3getByPlaceholderTextOnly if no label available
4getByTextNon-interactive elements
5getByTestIdLast resort only

Query Types

TypeWhen to Use
getBy/getAllByElement exists (throws if not found)
queryBy/queryAllByOnly for asserting absence
findBy/findAllByAsync elements (returns Promise)

Best Practices

typescript
// 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

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

Related

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