feat(cli): introduce new --last flag, to stop recommending HEAD~1 (#3916)

* test(cli): add regression test

* feat(cli): implement new `--last` CLI flag

The upgrade of ES2017 to ES2022 is because of the use of
`Object.hasOwn` API which is less ugly than hardcoding
`undefined`.

* docs(ci): stop recommending HEAD~1

In a single-commit repo, this would lead to this error:

```
Error: fatal: ambiguous argument 'HEAD~1..HEAD': unknown revision
or path not in the working tree.
```

Now that we have the `--last` flag, this should work for the case
in which we want just to analyze the last commit, not specify a
range of commits via `--from` and `--to`.

Closes #3892

* fix: use --pretty=format:"%B" instead of --pretty=%B

The latter adds unnecessary whitespace at the end of the commit
msg.

---------

Co-authored-by: Mehrshad <code.rezaei@gmail.com>

Author: knocte

@commitlint/cli/src/cli.test.ts

@@ -52,6 +52,16 @@ test('should produce success output with --verbose flag', async () => {
 	expect(actual.stderr).toEqual('');
 });
 
+test('should produce last commit and success output with --verbose flag', async () => {
+	const cwd = await gitBootstrap('fixtures/simple');
+	await execa('git', ['add', 'commitlint.config.js'], {cwd});
+	await execa('git', ['commit', '-m', '"test: this should work"'], {cwd});
+	const actual = await cli(['--last', '--verbose'], {cwd})();
+	expect(actual.stdout).toContain('0 problems, 0 warnings');
+	expect(actual.stdout).toContain('test: this should work');
+	expect(actual.stderr).toEqual('');
+});
+
 test('should produce no output with --quiet flag', async () => {
 	const cwd = await gitBootstrap('fixtures/default');
 	const actual = await cli(['--quiet'], {cwd})('foo: bar');
@@ -529,6 +539,7 @@ test('should print help', async () => {
 		  -H, --help-url       help url in error message  [string]
 		  -f, --from           lower end of the commit range to lint; applies if edit=false  [string]
 		      --git-log-args   additional git log arguments as space separated string, example '--first-parent --cherry-pick'  [string]
+		  -l, --last           just analyze the last commit; applies if edit=false  [boolean]
 		  -o, --format         output format of the results  [string]
 		  -p, --parser-preset  configuration preset to use for conventional-commits-parser  [string]
 		  -q, --quiet          toggle console output  [boolean] [default: false]

@commitlint/cli/src/cli.ts

@@ -95,6 +95,11 @@ const cli = yargs(process.argv.slice(2))
 				"additional git log arguments as space separated string, example '--first-parent --cherry-pick'",
 			type: 'string',
 		},
+		last: {
+			alias: 'l',
+			description: 'just analyze the last commit; applies if edit=false',
+			type: 'boolean',
+		},
 		format: {
 			alias: 'o',
 			description: 'output format of the results',
@@ -214,11 +219,25 @@ async function main(args: MainArgs): Promise<void> {
 
 	const fromStdin = checkFromStdin(raw, flags);
 
+	if (
+		Object.hasOwn(flags, 'last') &&
+		(Object.hasOwn(flags, 'from') || Object.hasOwn(flags, 'to') || flags.edit)
+	) {
+		const err = new CliError(
+			'Please use the --last flag alone. The --last flag should not be used with --to or --from or --edit.',
+			pkg.name
+		);
+		cli.showHelp('log');
+		console.log(err.message);
+		throw err;
+	}
+
 	const input = await (fromStdin
 		? stdin()
 		: read({
 				to: flags.to,
 				from: flags.from,
+				last: flags.last,
 				edit: flags.edit,
 				cwd: flags.cwd,
 				gitLogArgs: flags['git-log-args'],
@@ -231,7 +250,7 @@ async function main(args: MainArgs): Promise<void> {
 
 	if (messages.length === 0 && !checkFromRepository(flags)) {
 		const err = new CliError(
-			'[input] is required: supply via stdin, or --env or --edit or --from and --to',
+			'[input] is required: supply via stdin, or --env or --edit or --last or --from and --to',
 			pkg.name
 		);
 		cli.showHelp('log');
@@ -374,7 +393,11 @@ function checkFromEdit(flags: CliFlags): boolean {
 }
 
 function checkFromHistory(flags: CliFlags): boolean {
-	return typeof flags.from === 'string' || typeof flags.to === 'string';
+	return (
+		typeof flags.from === 'string' ||
+		typeof flags.to === 'string' ||
+		typeof flags.last === 'boolean'
+	);
 }
 
 function normalizeFlags(flags: CliFlags): CliFlags {

@commitlint/cli/src/types.ts

@@ -9,6 +9,7 @@ export interface CliFlags {
 	'help-url'?: string;
 	from?: string;
 	'git-log-args'?: string;
+	last?: boolean;
 	format?: string;
 	'parser-preset'?: string;
 	quiet: boolean;

@commitlint/read/package.json

@@ -39,14 +39,14 @@
     "@commitlint/test": "^19.0.0",
     "@commitlint/utils": "^19.0.0",
     "@types/git-raw-commits": "^2.0.3",
-    "@types/minimist": "^1.2.4",
-    "execa": "^8.0.1"
+    "@types/minimist": "^1.2.4"
   },
   "dependencies": {
     "@commitlint/top-level": "^19.0.0",
     "@commitlint/types": "^19.0.3",
     "git-raw-commits": "^4.0.0",
-    "minimist": "^1.2.8"
+    "minimist": "^1.2.8",
+    "execa": "^8.0.1"
   },
   "gitHead": "70f7f4688b51774e7ac5e40e896cdaa3f132b2bc"
 }

@commitlint/read/src/read.ts

@@ -4,10 +4,13 @@ import type {GitOptions} from 'git-raw-commits';
 import {getHistoryCommits} from './get-history-commits.js';
 import {getEditCommit} from './get-edit-commit.js';
 
+import {execa} from 'execa';
+
 interface GetCommitMessageOptions {
 	cwd?: string;
 	from?: string;
 	to?: string;
+	last?: boolean;
 	edit?: boolean | string;
 	gitLogArgs?: string;
 }
@@ -16,12 +19,21 @@ interface GetCommitMessageOptions {
 export default async function getCommitMessages(
 	settings: GetCommitMessageOptions
 ): Promise<string[]> {
-	const {cwd, from, to, edit, gitLogArgs} = settings;
+	const {cwd, from, to, last, edit, gitLogArgs} = settings;
 
 	if (edit) {
 		return getEditCommit(cwd, edit);
 	}
 
+	if (last) {
+		const executeGitCommand = await execa('git', [
+			'log',
+			'-1',
+			'--pretty=format:"%B"',
+		]);
+		return [executeGitCommand.stdout];
+	}
+
 	let gitOptions: GitOptions = {from, to};
 	if (gitLogArgs) {
 		gitOptions = {

docs/guides/ci-setup.md

@@ -42,7 +42,7 @@ jobs:
 
       - name: Validate current commit (last commit) with commitlint
         if: github.event_name == 'push'
-        run: npx commitlint --from HEAD~1 --to HEAD --verbose
+        run: npx commitlint --last --verbose
 
       - name: Validate PR commits with commitlint
         if: github.event_name == 'pull_request'

tsconfig.shared.json

@@ -1,7 +1,7 @@
 {
   "compilerOptions": {
-    "target": "ES2017",
-    "lib": ["es2017"],
+    "target": "ES2022",
+    "lib": ["es2022"],
     "declaration": true,
     "declarationMap": true,
     "sourceMap": true,