fix: warn about shallow clones

Author: marionebl

package.json

@@ -66,7 +66,7 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/marionebl/conventional-changelog-lint.git"
+    "url": "https://github.com/marionebl/conventional-changelog-lint.git"
   },
   "bugs": {
     "url": "https://github.com/marionebl/conventional-changelog-lint/issues"

source/library/get-messages.js

@@ -1,4 +1,5 @@
 import {join} from 'path';
+import exists from 'path-exists';
 import gitRawCommits from 'git-raw-commits';
 import gitToplevel from 'git-toplevel';
 import {readFile} from 'mz/fs';
@@ -14,6 +15,10 @@ async function getCommitMessages(settings) {
 		return getEditCommit();
 	}
 
+	if (await isShallow()) {
+		throw new Error('Could not get git history from shallow clone. Original issue: https://git.io/vyKMq\n Refer to https://git.io/vyKMv for details.');
+	}
+
 	return await getHistoryCommits({from, to});
 }
 
@@ -31,6 +36,14 @@ function getHistoryCommits(options) {
 	});
 }
 
+// Check if the current repository is shallow
+// () => Promise<Boolean>
+async function isShallow() {
+	const top = await gitToplevel();
+	const shallow = join(top, '.git/shallow');
+	return await exists(shallow);
+}
+
 // Get recently edited commit message
 // () => Promise<Array<String>>
 async function getEditCommit() {

test/integration/get-messages.js

@@ -11,6 +11,7 @@ import rimraf from 'rimraf';
 import expect from 'unexpected';
 
 import getMessages from '../../source/library/get-messages';
+import pkg from '../../package';
 
 const rm = denodeify(rimraf);
 
@@ -60,6 +61,22 @@ test.serial('get edit commit message from git subdirectory', async () => {
 	await cleanRepository(repo);
 });
 
+test.serial('get history commit messages from shallow clone', async () => {
+	const repo = await initRepository();
+
+	await writeFile('alpha.txt', 'alpha');
+	await execa('git', ['add', 'alpha.txt']);
+	await execa('git', ['commit', '-m', 'alpha']);
+
+	const clone = await cloneRepository(pkg.repository.url, repo, '--depth', '1');
+
+	const actual = async () => await getMessages({from: 'master'});
+	expect(actual, 'to error with', /Could not get git history from shallow clone/);
+
+	await cleanRepository(clone);
+	await cleanRepository(repo);
+});
+
 async function initRepository() {
 	const previous = process.cwd();
 	const directory = join(tmpdir(), rand());
@@ -74,6 +91,17 @@ async function initRepository() {
 	return {directory, previous};
 }
 
+async function cloneRepository(source, context, ...args) {
+	const directory = join(tmpdir(), rand());
+	await execa('git', ['clone', ...args, source, directory]);
+	process.chdir(directory);
+
+	await execa('git', ['config', 'user.email', '[email protected]']);
+	await execa('git', ['config', 'user.name', 'ava']);
+
+	return {directory, previous: context.previous};
+}
+
 async function cleanRepository(repo) {
 	process.chdir(repo.previous);