subject-exclamation-mark.ts

import message from '@commitlint/message';
import {SyncRule} from '@commitlint/types';

export const subjectExclamationMark: SyncRule = (parsed, when = 'always') => {
	const input = parsed.header;
	if (!input) {
		return [true, ''];
	}

	const negated = when === 'never';
	const hasExclamationMark = /!:/.test(input);

	return [
		negated ? !hasExclamationMark : hasExclamationMark,
		message([
			'subject',
			negated ? 'must not' : 'must',
			'have an exclamation mark in the subject to identify a breaking change',
		]),
	];
};