validate-commit-msg

const validateMessage = require('validate-commit-msg');

const { getConfig, getRcConfig, getPackageConfig, getConfigObject } = require('validate-commit-msg/lib/config');
const getGitFolder = require('validate-commit-msg/lib/getGitFolder');

const validateMessage = require('validate-commit-msg');

// Validate a commit message programmatically
const isValid = validateMessage('feat(auth): add user login functionality');
console.log(isValid); // true

// Invalid commit message
const isInvalid = validateMessage('bad commit message');
console.log(isInvalid); // false

// Validate with auto-fix (requires source file path)
const result = validateMessage('FEAT: uppercase type', '.git/COMMIT_EDITMSG');
// Auto-fixes the type to lowercase if autoFix is enabled in config

# Install as git hook (using husky)
npm install --save-dev husky validate-commit-msg

# Add to package.json scripts
{
  "scripts": {
    "commitmsg": "validate-commit-msg"
  }
}

# Direct CLI usage
validate-commit-msg "feat(scope): commit message"
validate-commit-msg  # reads from COMMIT_EDITMSG file
validate-commit-msg GITGUI_EDITMSG  # reads from specified git file

{
  "config": {
    "validate-commit-msg": {
      "types": ["feat", "fix", "docs", "style", "refactor", "test", "chore"],
      "scope": {
        "required": false,
        "allowed": ["*"],
        "validate": false,
        "multiple": false
      },
      "warnOnFail": false,
      "maxSubjectLength": 100,
      "subjectPattern": ".+",
      "subjectPatternErrorMsg": "subject does not match subject pattern!",
      "helpMessage": "",
      "autoFix": false
    }
  }
}

/**
 * Validates a commit message against conventional changelog format
 * @param {string} raw - Raw commit message text to validate
 * @param {string} [sourceFile] - Optional path to commit message file for auto-fixing
 * @returns {boolean} true if message is valid, false otherwise
 */
function validateMessage(raw, sourceFile);

/**
 * Get merged configuration from .vcmrc and package.json
 * @returns {object} Configuration object with validation settings
 */
function getConfig();

/**
 * Get configuration from .vcmrc file
 * @returns {object|null} Configuration from .vcmrc or null if not found
 */
function getRcConfig();

/**
 * Get configuration from package.json
 * @returns {object|null} Configuration from package.json config.validate-commit-msg or null if not found
 */
function getPackageConfig();

/**
 * Get configuration from specified file
 * @param {string} filename - Configuration file name to read (e.g., '.vcmrc', 'package.json')
 * @returns {object|null} Parsed configuration object or null if not found
 */
function getConfigObject(filename);

/**
 * Locate .git folder in current directory tree
 * @returns {string} Path to .git folder
 * @throws {Error} If .git folder cannot be found
 */
function getGitFolder();

const { config } = require('validate-commit-msg/lib/validateMessage');

/**
 * Current configuration object used by the validator
 * Contains merged settings from .vcmrc and package.json
 * @type {object}
 */
const config;

/**
 * Configuration object structure for validate-commit-msg
 */
interface ValidateCommitMsgConfig {
  /** 
   * Allowed commit types. Can be:
   * - Array of strings: ["feat", "fix", "docs"]
   * - "*" for any type
   * - Module name: "conventional-commit-types" (default)
   */
  types?: string[] | "*" | string;
  
  /** Scope validation configuration */
  scope?: {
    /** Whether scope is required for all commits */
    required?: boolean;
    /** Array of allowed scopes or "*" for any scope */
    allowed?: string[] | "*";
    /** Whether to validate scope names against allowed list */
    validate?: boolean;
    /** Whether multiple scopes are allowed (comma-separated) */
    multiple?: boolean;
  };
  
  /** If true, validation errors are warnings instead of failures */
  warnOnFail?: boolean;
  
  /** Maximum allowed subject length (default: 100) */
  maxSubjectLength?: number;
  
  /** Regular expression pattern for subject validation (default: ".+") */
  subjectPattern?: string;
  
  /** Error message when subject doesn't match pattern */
  subjectPatternErrorMsg?: string;
  
  /** Custom help message shown on validation failure */
  helpMessage?: string;
  
  /** Enable automatic fixing of common formatting issues (requires sourceFile parameter) */
  autoFix?: boolean;
}

const validateMessage = require('validate-commit-msg');

// Valid messages
console.log(validateMessage('feat: add new feature')); // true
console.log(validateMessage('fix(auth): resolve login issue')); // true
console.log(validateMessage('docs: update README')); // true

// Invalid messages
console.log(validateMessage('bad message')); // false
console.log(validateMessage('FEAT: uppercase type')); // false (unless autoFix enabled)

// Auto-merge commits are always valid
console.log(validateMessage('Merge branch "feature" into main')); // true

// WIP and semver commits are ignored
console.log(validateMessage('WIP: work in progress')); // true
console.log(validateMessage('v1.2.3')); // true

const { getConfig, getRcConfig, getPackageConfig, getConfigObject } = require('validate-commit-msg/lib/config');

// Get current merged configuration
const config = getConfig();
console.log('Max subject length:', config.maxSubjectLength);
console.log('Allowed types:', config.types);

// Check specific config sources
const rcConfig = getRcConfig(); // From .vcmrc
const pkgConfig = getPackageConfig(); // From package.json

// Read any config file
const customConfig = getConfigObject('my-config.json');

// In a git hook script
const validateMessage = require('validate-commit-msg');
const getGitFolder = require('validate-commit-msg/lib/getGitFolder');
const fs = require('fs');
const path = require('path');

try {
  const gitDir = getGitFolder();
  const commitMsgPath = path.join(gitDir, 'COMMIT_EDITMSG');
  const commitMsg = fs.readFileSync(commitMsgPath, 'utf8');
  
  // Validate with auto-fix capability
  if (!validateMessage(commitMsg, commitMsgPath)) {
    console.error('Invalid commit message format');
    process.exit(1);
  }
} catch (error) {
  console.error('Error reading commit message:', error.message);
  process.exit(1);
}

// .vcmrc configuration file
{
  "types": ["feat", "fix", "docs", "style", "refactor", "test", "chore"],
  "scope": {
    "required": true,
    "allowed": ["auth", "api", "ui", "core"],
    "validate": true,
    "multiple": false
  },
  "warnOnFail": false,
  "maxSubjectLength": 72,
  "subjectPattern": "^[a-z].*[^.]$",
  "subjectPatternErrorMsg": "Subject must start with lowercase and not end with period",
  "helpMessage": "Please follow the conventional commit format: <type>(<scope>): <subject>",
  "autoFix": true
}