Configuration Hygiene Fixes

Fixes for project configuration issues. Clean configs prevent noise, ensure consistency, and improve developer experience.

Quick Start

1. Identify the config issue (gitignore, ESLint, husky)
2. Apply the recommended fix
3. Verify no unintended side effects
4. Commit config changes

Priority Matrix

Issue	Priority	Impact
Backup files in repo	P2	Noise, confusion
Missing gitignore patterns	P2	Unwanted files tracked
Husky silent failure	P2	Hidden hook failures
ESLint config duplication	P3	Maintenance burden
Permissive lint threshold	P2	Quality regression

---

Workflows

Backup/Artifact Files in Repository (#35 - 12 occurrences)

Detection: Files matching *.bak, *.orig, *~ patterns.

Pattern: Editor/merge artifacts committed to repo.

Fix Strategy: Remove from git, add to gitignore.

# Remove from git (keep locally)
git rm --cached "*.bak"
git rm --cached "*.orig"
git rm --cached "*~"

# Add to .gitignore
echo "*.bak" >> .gitignore
echo "*.orig" >> .gitignore
echo "*~" >> .gitignore

# Commit
git add .gitignore
git commit -m "chore: ignore backup/artifact files"

---

Missing .gitignore Patterns (#36 - 8 occurrences)

Detection: Common patterns not in .gitignore.

Fix Strategy: Add comprehensive patterns.

# Editor artifacts
*.swp
*.swo
*~
*.bak
*.orig

# OS files
.DS_Store
Thumbs.db

# IDE
.idea/
.vscode/
*.sublime-*

# Build outputs
dist/
build/
*.tsbuildinfo

# Dependencies
node_modules/

# Environment
.env
.env.*
!.env.example

# Logs
*.log
npm-debug.log*
yarn-debug.log*
yarn-error.log*

# Test coverage
coverage/
.nyc_output/

# Cache
.cache/
.eslintcache
.parcel-cache/

Template: See templates/gitignore-node.txt for complete Node.js template.

---

Husky Prepare Script Silent Failure (#37 - 1 occurrence)

Detection: prepare script uses || true fallback.

Pattern: Hook installation fails silently.

// PROBLEM - hides failures
{
  "scripts": {
    "prepare": "husky install || true"
  }
}

Fix Strategy 1: Conditional execution based on CI.

// SOLUTION - check CI environment
{
  "scripts": {
    "prepare": "node -e \"if (process.env.CI !== 'true') require('husky').install()\""
  }
}

Fix Strategy 2: Use is-ci package.

npm install --save-dev is-ci

{
  "scripts": {
    "prepare": "is-ci || husky install"
  }
}

Fix Strategy 3: Husky v9+ auto-setup.

// Husky v9 uses .husky/_/husky.sh automatically
{
  "scripts": {
    "prepare": "husky"
  }
}

---

Permissive lint:strict Threshold (#38 - 1 occurrence)

Detection: High --max-warnings value in lint script.

Pattern: Too many warnings allowed.

// PROBLEM - too permissive
{
  "scripts": {
    "lint:strict": "eslint . --max-warnings 500"
  }
}

Fix Strategy: Progressive reduction.

// Week 1: Lower to current count + small buffer
{
  "scripts": {
    "lint:strict": "eslint . --max-warnings 350"
  }
}

// Week 2: Lower further
{
  "scripts": {
    "lint:strict": "eslint . --max-warnings 200"
  }
}

// Target: Zero tolerance
{
  "scripts": {
    "lint:strict": "eslint . --max-warnings 0"
  }
}

Tracking Progress:

# Get current warning count
npx eslint . 2>&1 | tail -1
# Output: "X warnings" or "X problems (Y errors, Z warnings)"

---

ESLint Config Duplication (#39, #40)

Issue #39: Repeated plugin/globals definitions.

// PROBLEM - repeated in multiple blocks
export default [
  {
    files: ['**/*.ts'],
    plugins: { '@typescript-eslint': tsPlugin },
  },
  {
    files: ['**/*.tsx'],
    plugins: { '@typescript-eslint': tsPlugin },  // Duplicated
  },
];

Fix Strategy: Extract shared config.

// SOLUTION - shared base config
const baseTypescriptConfig = {
  plugins: {
    '@typescript-eslint': tsPlugin,
  },
  languageOptions: {
    parser: tsParser,
    parserOptions: {
      project: './tsconfig.json',
    },
  },
};

export default [
  {
    files: ['**/*.ts'],
    ...baseTypescriptConfig,
    rules: { /* ts-specific rules */ },
  },
  {
    files: ['**/*.tsx'],
    ...baseTypescriptConfig,
    rules: { /* tsx-specific rules */ },
  },
];

Issue #40: Disabled rules duplicated across blocks.

// PROBLEM - duplicated disabled rules
{
  rules: {
    '@typescript-eslint/no-explicit-any': 'off',
    '@typescript-eslint/no-unsafe-assignment': 'off',
  },
},

Fix Strategy: Extract to named constant with documentation.

// SOLUTION - extracted with docs
/**
 * Rules disabled during migration to strict TypeScript.
 * TODO: Re-enable progressively - see issue #456
 */
const migrationDisabledRules = {
  '@typescript-eslint/no-explicit-any': 'off',
  '@typescript-eslint/no-unsafe-assignment': 'off',
  '@typescript-eslint/no-unsafe-member-access': 'off',
} as const;

export default [
  {
    files: ['**/*.ts'],
    rules: {
      ...migrationDisabledRules,
      // ts-specific rules
    },
  },
];

---

Recursive Directory Walking Without Limits (#23 - 1 occurrence)

Pattern: Unbounded recursion in file walking.

// PROBLEM - no limits
async function walkDir(dir: string): Promise<string[]> {
  const entries = await fs.readdir(dir, { withFileTypes: true });
  const files: string[] = [];
  for (const entry of entries) {
    if (entry.isDirectory()) {
      files.push(...await walkDir(path.join(dir, entry.name))); // No limit!
    }
  }
  return files;
}

Fix Strategy: Add depth limit and visited tracking.

// SOLUTION - with limits
interface WalkOptions {
  maxDepth?: number;
  maxFiles?: number;
}

async function walkDir(
  dir: string,
  options: WalkOptions = {},
  depth = 0,
  visited = new Set<string>()
): Promise<string[]> {
  const { maxDepth = 10, maxFiles = 10000 } = options;

  if (depth > maxDepth) {
    return [];
  }

  const realPath = await fs.realpath(dir);
  if (visited.has(realPath)) {
    return []; // Circular symlink
  }
  visited.add(realPath);

  const entries = await fs.readdir(dir, { withFileTypes: true });
  const files: string[] = [];

  for (const entry of entries) {
    if (files.length >= maxFiles) break;

    const fullPath = path.join(dir, entry.name);
    if (entry.isDirectory()) {
      files.push(...await walkDir(fullPath, options, depth + 1, visited));
    } else {
      files.push(fullPath);
    }
  }

  return files;
}

---

Regex Created Per-Match (#24 - 1 occurrence)

Pattern: Regex compiled on every function call.

// PROBLEM - regex created every call
function containsKeyword(text: string, keyword: string): boolean {
  const regex = new RegExp(`\\b${keyword}\\b`, 'i');
  return regex.test(text);
}

Fix Strategy: Pre-compile and cache.

// SOLUTION - cached regex
const keywordRegexCache = new Map<string, RegExp>();

function getKeywordRegex(keyword: string): RegExp {
  let regex = keywordRegexCache.get(keyword);
  if (!regex) {
    regex = new RegExp(`\\b${escapeRegex(keyword)}\\b`, 'i');
    keywordRegexCache.set(keyword, regex);
  }
  return regex;
}

function escapeRegex(str: string): string {
  return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
}

function containsKeyword(text: string, keyword: string): boolean {
  return getKeywordRegex(keyword).test(text);
}

---

Scripts

Check Config Hygiene

node scripts/check-config.js

Fix Gitignore

node scripts/fix-gitignore.js

---

Templates

Node.js .gitignore

See templates/gitignore-node.txt

ESLint Base Config

See templates/eslint-base.js

---

CI/CD Considerations

Ensuring Hooks Run

# GitHub Actions
- name: Install dependencies
  run: npm ci

# This runs "prepare" script which installs husky
# Make sure CI=true is set to skip if needed

Lint in CI

- name: Lint
  run: npm run lint:strict
  # Fails if warnings exceed threshold

Progressive Strictness

# Allow gradual improvement
- name: Check lint progress
  run: |
    WARNINGS=$(npx eslint . 2>&1 | grep -oP '\d+ warning' | grep -oP '\d+' || echo "0")
    THRESHOLD=200
    if [ "$WARNINGS" -gt "$THRESHOLD" ]; then
      echo "Too many warnings: $WARNINGS (max: $THRESHOLD)"
      exit 1
    fi