feat: add async promise based rules methods into lint (#976)

* feat(rules): add async promise based rules methods into lint

* fix: accomodate async rules in type system

* style: apply autoformatting

Author: marionebl

@commitlint/lint/src/lint.test.ts

@@ -283,3 +283,23 @@ test('returns original message with commit header, body and footer, parsing comm
 
 	expect(report.input).toBe(expected);
 });
+
+test('passes for async rule', async () => {
+	const report = await lint(
+		'somehting #1',
+		{
+			'async-rule': [2, 'never']
+		},
+		{
+			plugins: {
+				'example-plugin': {
+					rules: {
+						'async-rule': async () => [true, 'all good'] as const
+					}
+				}
+			}
+		}
+	);
+
+	expect(report.valid).toBe(true);
+});

@commitlint/lint/src/lint.ts

@@ -8,7 +8,9 @@ import {
 	LintOptions,
 	LintRuleOutcome,
 	Rule,
-	RuleSeverity
+	RuleSeverity,
+	BaseRule,
+	RuleType
 } from '@commitlint/types';
 
 export default async function lint(
@@ -35,7 +37,7 @@ export default async function lint(
 
 	// Parse the commit message
 	const parsed = await parse(message, undefined, opts.parserOpts);
-	const allRules: Map<string, Rule<unknown> | Rule<never>> = new Map(
+	const allRules: Map<string, BaseRule<never, RuleType>> = new Map(
 		Object.entries(defaultRules)
 	);
 
@@ -130,9 +132,9 @@ export default async function lint(
 	}
 
 	// Validate against all rules
-	const results = Object.entries(rulesConfig)
+	const pendingResults = Object.entries(rulesConfig)
 		.filter(([, [level]]) => level > 0)
-		.map(entry => {
+		.map(async entry => {
 			const [name, config] = entry;
 			const [level, when, value] = config;
 
@@ -148,16 +150,19 @@ export default async function lint(
 			}
 
 			const executableRule = rule as Rule<unknown>;
-			const [valid, message] = executableRule(parsed, when, value);
+			const [valid, message] = await executableRule(parsed, when, value);
 
 			return {
 				level,
 				valid,
 				name,
 				message
 			};
-		})
-		.filter((result): result is LintRuleOutcome => result !== null);
+		});
+
+	const results = (await Promise.all(pendingResults)).filter(
+		(result): result is LintRuleOutcome => result !== null
+	);
 
 	const errors = results.filter(result => result.level === 2 && !result.valid);
 	const warnings = results.filter(

@commitlint/rules/src/body-case.ts

@@ -1,8 +1,8 @@
 import {case as ensureCase} from '@commitlint/ensure';
 import message from '@commitlint/message';
-import {TargetCaseType, Rule} from '@commitlint/types';
+import {TargetCaseType, SyncRule} from '@commitlint/types';
 
-export const bodyCase: Rule<TargetCaseType> = (
+export const bodyCase: SyncRule<TargetCaseType> = (
 	parsed,
 	when = 'always',
 	value = undefined

@commitlint/rules/src/body-empty.ts

@@ -1,8 +1,8 @@
 import * as ensure from '@commitlint/ensure';
 import message from '@commitlint/message';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const bodyEmpty: Rule = (parsed, when = 'always') => {
+export const bodyEmpty: SyncRule = (parsed, when = 'always') => {
 	const negated = when === 'never';
 	const notEmpty = ensure.notEmpty(parsed.body || '');
 

@commitlint/rules/src/body-leading-blank.ts

@@ -1,8 +1,8 @@
 import toLines from '@commitlint/to-lines';
 import message from '@commitlint/message';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const bodyLeadingBlank: Rule = (parsed, when) => {
+export const bodyLeadingBlank: SyncRule = (parsed, when) => {
 	// Flunk if no body is found
 	if (!parsed.body) {
 		return [true];

@commitlint/rules/src/body-max-length.ts

@@ -1,7 +1,7 @@
 import {maxLength} from '@commitlint/ensure';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const bodyMaxLength: Rule<number> = (
+export const bodyMaxLength: SyncRule<number> = (
 	parsed,
 	_when = undefined,
 	value = 0

@commitlint/rules/src/body-max-line-length.ts

@@ -1,7 +1,7 @@
 import {maxLineLength} from '@commitlint/ensure';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const bodyMaxLineLength: Rule<number> = (
+export const bodyMaxLineLength: SyncRule<number> = (
 	parsed,
 	_when = undefined,
 	value = 0

@commitlint/rules/src/body-min-length.ts

@@ -1,7 +1,7 @@
 import {minLength} from '@commitlint/ensure';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const bodyMinLength: Rule<number> = (
+export const bodyMinLength: SyncRule<number> = (
 	parsed,
 	_when = undefined,
 	value = 0

@commitlint/rules/src/footer-empty.ts

@@ -1,8 +1,8 @@
 import * as ensure from '@commitlint/ensure';
 import message from '@commitlint/message';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const footerEmpty: Rule = (parsed, when = 'always') => {
+export const footerEmpty: SyncRule = (parsed, when = 'always') => {
 	const negated = when === 'never';
 	const notEmpty = ensure.notEmpty(parsed.footer || '');
 

@commitlint/rules/src/footer-leading-blank.ts

@@ -1,8 +1,8 @@
 import toLines from '@commitlint/to-lines';
 import message from '@commitlint/message';
-import {Rule} from '@commitlint/types';
+import {SyncRule} from '@commitlint/types';
 
-export const footerLeadingBlank: Rule = (parsed, when = 'always') => {
+export const footerLeadingBlank: SyncRule = (parsed, when = 'always') => {
 	// Flunk if no footer is found
 	if (!parsed.footer) {
 		return [true];