Pre-Commit Setup

Analyze the repository and create a configuration file for pre-push checks.

What This Does

•Scans the repository for ecosystem indicators (JS/TS, Python, Rust, Go)
•Detects available typecheck, lint, build, and test tools
•Creates .claude/pre-commit.json with discovered configuration
•Reports what was found and how to customize

Setup Process

Step 1: Detect Ecosystems

Check for these files in the project root:

File	Ecosystem
`package.json`	JavaScript/TypeScript
`tsconfig.json`	TypeScript (confirms JS ecosystem)
`pyproject.toml`, `setup.py`, `requirements.txt`	Python
`Cargo.toml`	Rust
`go.mod`	Go

Run these checks:

bash

# Check what exists
ls -la package.json tsconfig.json pyproject.toml setup.py requirements.txt Cargo.toml go.mod 2>/dev/null

Step 2: Detect Tools Per Ecosystem

JavaScript/TypeScript

Typecheck detection:

bash

# Check for TypeScript
if [ -f "tsconfig.json" ]; then
  # Check package.json for typecheck script
  grep -q '"typecheck"' package.json 2>/dev/null && echo "npm run typecheck"
  grep -q '"type-check"' package.json 2>/dev/null && echo "npm run type-check"
  # Fallback to tsc
  grep -q '"typescript"' package.json 2>/dev/null && echo "npx tsc --noEmit"
fi

Lint detection:

bash

# Check for lint script first
grep -q '"lint"' package.json 2>/dev/null && echo "npm run lint"

# Check for ESLint config
ls eslint.config.* .eslintrc* 2>/dev/null && echo "npx eslint ."

# Check for Biome
[ -f "biome.json" ] && echo "npx biome check ."

Build detection:

bash

# Check for build script
grep -q '"build"' package.json && echo "npm run build"

# Check for Turbo
[ -f "turbo.json" ] && echo "turbo run build"

# Check for monorepo workspaces
[ -f "pnpm-workspace.yaml" ] && echo "pnpm -r build"
[ -f "lerna.json" ] && echo "lerna run build"

Test detection:

bash

# Check for test script
grep -q '"test"' package.json 2>/dev/null && echo "npm test"

# Detect test runner
grep -q '"vitest"' package.json 2>/dev/null && echo "vitest"
grep -q '"jest"' package.json 2>/dev/null && echo "jest"

Package manager detection:

bash

[ -f "pnpm-lock.yaml" ] && echo "pnpm"
[ -f "yarn.lock" ] && echo "yarn"
[ -f "bun.lockb" ] && echo "bun"
[ -f "package-lock.json" ] && echo "npm"

Python

Typecheck detection:

bash

# Check pyproject.toml for mypy or pyright
grep -q "mypy" pyproject.toml 2>/dev/null && echo "mypy ."
grep -q "pyright" pyproject.toml 2>/dev/null && echo "pyright"
[ -f "mypy.ini" ] && echo "mypy ."
[ -f "pyrightconfig.json" ] && echo "pyright"

Lint detection:

bash

# Check for ruff (preferred)
grep -q "ruff" pyproject.toml 2>/dev/null && echo "ruff check ."
[ -f "ruff.toml" ] && echo "ruff check ."

# Fallback to flake8
grep -q "flake8" pyproject.toml 2>/dev/null && echo "flake8"
[ -f ".flake8" ] && echo "flake8"

Build detection:

bash

[ -f "pyproject.toml" ] && grep -q "\[build-system\]" pyproject.toml && echo "python -m build"

Test detection:

bash

# pytest is most common
grep -q "pytest" pyproject.toml 2>/dev/null && echo "pytest"
[ -f "pytest.ini" ] && echo "pytest"
[ -d "tests" ] && echo "pytest"

Rust

bash

if [ -f "Cargo.toml" ]; then
  echo "typecheck: cargo check"
  echo "lint: cargo clippy -- -D warnings"
  echo "build: cargo build --release"
  echo "test: cargo test"
fi

Go

bash

if [ -f "go.mod" ]; then
  echo "typecheck: go build ./..."
  # Check for golangci-lint config
  [ -f ".golangci.yml" ] || [ -f ".golangci.yaml" ] && echo "lint: golangci-lint run"
  echo "build: go build ./..."
  echo "test: go test ./..."
fi

Step 3: Generate Configuration

Create .claude/pre-commit.json:

json

{
  "version": 1,
  "checks": {
    "typecheck": {
      "enabled": true,
      "mode": "block",
      "command": "<detected-command>"
    },
    "lint": {
      "enabled": true,
      "mode": "block",
      "command": "<detected-command>"
    },
    "build": {
      "enabled": true,
      "mode": "block",
      "command": "<detected-command>"
    },
    "test": {
      "enabled": true,
      "mode": "block",
      "command": "<detected-command>"
    }
  },
  "detected": {
    "ecosystem": "<ecosystem>",
    "packageManager": "<pm>",
    "tools": ["<tool1>", "<tool2>"]
  }
}

Rules:

•If a check cannot be detected, set "enabled": false and "command": ""
•Default mode is "block" for all checks
•For multi-ecosystem repos, combine commands with &&
•For monorepos, use manual override with filter commands (e.g., pnpm --filter @scope/pkg build)

Step 4: Report to User

After creating the config, output:

code

Created .claude/pre-commit.json

Detected ecosystem: JavaScript/TypeScript (npm)

Checks configured:
  typecheck: npm run typecheck (block)
  lint: npm run lint (block)
  build: npm run build (block)
  test: npm test (block)

These checks will run before git push. Edit the file to:
- Change mode from "block" to "warn" for softer enforcement
- Modify commands if the detected ones aren't correct
- Disable checks by setting "enabled": false
- For monorepos, use filter commands like "pnpm --filter @scope/pkg build"

Multi-Ecosystem Example

For a repo with both package.json and pyproject.toml:

json

{
  "version": 1,
  "checks": {
    "typecheck": {
      "enabled": true,
      "mode": "block",
      "command": "npm run typecheck && mypy ."
    },
    "lint": {
      "enabled": true,
      "mode": "block",
      "command": "npm run lint && ruff check ."
    },
    "build": {
      "enabled": true,
      "mode": "block",
      "command": "npm run build && python -m build"
    },
    "test": {
      "enabled": true,
      "mode": "block",
      "command": "npm test && pytest"
    }
  },
  "detected": {
    "ecosystem": "javascript,python",
    "packageManager": "npm",
    "tools": ["typescript", "eslint", "vitest", "mypy", "ruff", "pytest"]
  }
}

Monorepo Example

For monorepos where you need targeted build commands:

json

{
  "version": 1,
  "checks": {
    "typecheck": {
      "enabled": true,
      "mode": "block",
      "command": "npm run typecheck"
    },
    "lint": {
      "enabled": true,
      "mode": "block",
      "command": "npm run lint"
    },
    "build": {
      "enabled": true,
      "mode": "block",
      "command": "pnpm --filter @e2/shared build"
    },
    "test": {
      "enabled": true,
      "mode": "block",
      "command": "npm test"
    }
  }
}

Updating Configuration

If the user asks to "refresh" or "update" pre-commit config:

•Re-run detection
•Preserve existing mode settings from current config
•Update commands if tools changed
•Report what changed