gh-xloxn69-agileflow/commands/impact.md

description, allowed-tools

description	allowed-tools
impact-analysis	Bash, Read, Edit, Write, Glob, Grep

impact-analysis

Analyze the impact of code changes on other parts of the codebase.

Prompt

ROLE: Impact Analyzer

OBJECTIVE Identify which files, tests, and features are affected by code changes to prevent regressions.

INPUTS (optional)

• FILES= (default: auto-detect from git diff)
• BASE= (default: main/master)
• RUN_TESTS=yes|no (default: yes, if tests found)

DETECTION

1. Get changed files:

   git diff <BASE>...HEAD --name-only
   

2. For each changed file, find:

   • Direct imports: Files that import this file
   • Indirect imports: Files that import files that import this file (2 levels)
   • Test files: Corresponding test files (*.test*, *.spec*)
   • Related stories: Stories mentioning this file in docs/06-stories/

ANALYSIS METHODS

Static Analysis (AST parsing)

• Parse import/require statements
• Build dependency graph
• Identify circular dependencies
• Find dead code (exported but never imported)

Test Coverage Mapping

• Read coverage reports (coverage/lcov.info, coverage.json)
• Map changed lines to test files
• Identify uncovered changes

Pattern Matching

• API routes → API tests
• Components → Component tests + Storybook stories
• Services → Service tests + Integration tests
• Database models → Migration tests

IMPACT REPORT

# Impact Analysis Report

**Branch**: <BRANCH>
**Base**: <BASE>
**Changed Files**: 5
**Potentially Affected Files**: 23
**Tests to Run**: 12

## Direct Impacts

### src/api/auth/login.ts (MODIFIED)
**Type**: API endpoint
**Changes**: 23 lines modified

**Direct dependents** (3):
- src/api/auth/index.ts (exports this endpoint)
- src/middleware/auth.ts (uses login logic)
- tests/api/auth/login.test.ts (tests this file)

**Indirect dependents** (8):
- src/app.ts → src/api/auth/index.ts → login.ts
- src/routes.ts → src/api/auth/index.ts → login.ts
- [6 more...]

**Related tests**:
- ✅ tests/api/auth/login.test.ts (exists)
- ⚠️ tests/integration/auth-flow.test.ts (may need updates)
- ❌ Missing: E2E test for login flow

**Related stories**:
- US-0042: Implement JWT authentication (IN-REVIEW)

**Coverage**: 87% (lines 45-52 uncovered)

---

### src/components/LoginForm.tsx (MODIFIED)
**Type**: UI component
**Changes**: 15 lines modified

**Direct dependents** (2):
- src/pages/Login.tsx
- src/components/AuthModal.tsx

**Related tests**:
- ✅ tests/components/LoginForm.test.tsx (exists)
- ⚠️ Accessibility tests not found

**Related stories**:
- US-0041: Create login form UI (IN-REVIEW)

**Coverage**: 92%

Breaking Changes Detection

Analyze function signatures and types:

⚠️ BREAKING CHANGE DETECTED

File: src/api/auth/login.ts
Function: login()

Before:
  login(email: string, password: string): Promise<Token>

After:
  login(credentials: LoginRequest): Promise<AuthResponse>

Affected callers (3):
- src/middleware/auth.ts:45
- tests/api/auth/login.test.ts:23
- tests/integration/auth-flow.test.ts:67

Test Recommendations

Based on changes, suggest tests to run:

Critical (always run):

• tests/api/auth/login.test.ts (direct test)
• tests/integration/auth-flow.test.ts (integration)

Recommended (affected indirectly):

• tests/api/users/*.test.ts (uses auth)
• tests/e2e/login.spec.ts (E2E)

Optional (low risk):

• tests/components/Header.test.tsx (displays user from auth)

ACTIONS (after user review)

1. Show impact summary

2. Ask: "Run affected tests? (YES/NO)"

3. If YES:

   # Run only affected tests
   npm test -- tests/api/auth/login.test.ts tests/integration/auth-flow.test.ts
   

4. If tests fail:

   • Show failures
   • Suggest creating story: "US-XXXX: Fix regressions from "

5. If breaking changes detected:

   • Warn user
   • Suggest creating ADR if architectural change
   • Create stories for updating affected callers

INTEGRATION

CI Optimization

Suggest optimized CI that only runs affected tests:

- name: Impact analysis
  run: npx claude-code /AgileFlow:impact-analysis BASE=main

- name: Run affected tests
  run: npm test -- $(cat affected-tests.txt)

Story Updates

• Update related stories with impact notes
• Create new stories for regressions or breaking changes
• Append to bus/log.jsonl: {"type":"impact","affected":23,"tests":12}

VISUALIZATION (optional) Generate dependency graph:

src/api/auth/login.ts
├── src/api/auth/index.ts
│   ├── src/app.ts
│   └── src/routes.ts
├── src/middleware/auth.ts
│   └── src/app.ts
└── tests/api/auth/login.test.ts

RULES

• Use static analysis when possible (faster than running tests)
• Prioritize tests by risk (critical path first)
• Never skip tests for modified files
• Warn about uncovered changes
• Suggest creating tests for uncovered code
• Diff-first for any file modifications

OUTPUT

• Impact analysis report (markdown)
• List of affected files and tests
• Test recommendations (critical/recommended/optional)
• Optional: Run tests and report results