feat(prompt-cli): add test conventional-changelog#51

@commitlint/prompt-cli/cli.test.js

@@ -0,0 +1,25 @@
+import path from 'path';
+import {git} from '@commitlint/test';
+import test from 'ava';
+import execa from 'execa';
+import stream from 'string-to-stream';
+
+const bin = path.join(__dirname, './cli.js');
+
+const cli = (args, options) => {
+	return (input = '') => {
+		const c = execa(bin, args, {
+			capture: ['stdout'],
+			cwd: options.cwd,
+			env: options.env
+		});
+		stream(input).pipe(c.stdin);
+		return c.catch(err => err);
+	};
+};
+
+test('should print warning if stage is empty', async t => {
+	const cwd = await git.bootstrap();
+	const actual = await cli([], {cwd})('foo: bar');
+	t.true(actual.stdout.includes('Nothing to commit.'));
+});

@commitlint/prompt-cli/package.json

@@ -13,7 +13,8 @@
     "commit": "$npm_package_bin_commit",
     "deps": "dep-check",
     "pkg": "pkg-check --skip-main",
-    "lint": "xo"
+    "lint": "xo",
+    "test": "ava -c 4 --verbose"
   },
   "xo": false,
   "repository": {
@@ -36,7 +37,10 @@
   },
   "dependencies": {
     "@commitlint/prompt": "^7.2.0",
+    "@commitlint/test": "^7.1.2",
+    "ava": "^0.25.0",
     "execa": "0.9.0",
-    "meow": "3.7.0"
+    "meow": "3.7.0",
+    "string-to-stream": "^1.1.1"
   }
 }