Add an extra line when showing usage (jestjs#2539)

packages/jest-cli/src/__tests__/__snapshots__/watch-test.js.snap

@@ -0,0 +1,11 @@
+exports[`Watch mode flows Runs Jest once by default and shows usage 1`] = `
+Array [
+  "
+Watch Usage
+ › Press o to only run tests related to changed files.
+ › Press p to filter by a filename regex pattern.
+ › Press q to quit watch mode.
+ › Press Enter to trigger a test run.
+",
+]
+`;

packages/jest-cli/src/__tests__/watch-test.js

@@ -30,13 +30,6 @@ jest.doMock('../runJest', () => (...args) => {
 
 const watch = require('../watch');
 
-const USAGE_MESSAGE = `
-Watch Usage
- › Press o to only run tests related to changed files.
- › Press p to filter by a filename regex pattern.
- › Press q to quit watch mode.
- › Press Enter to trigger a test run.`;
-
 afterEach(runJestMock.mockReset);
 
 describe('Watch mode flows', () => {
@@ -60,7 +53,7 @@ describe('Watch mode flows', () => {
     watch(config, pipe, argv, hasteMap, hasteContext, stdin);
     expect(runJestMock).toBeCalledWith(hasteContext, config, argv, pipe,
       new TestWatcher({isWatchMode: true}), jasmine.any(Function));
-    expect(pipe.write).toBeCalledWith(USAGE_MESSAGE);
+    expect(pipe.write.mock.calls.reverse()[0]).toMatchSnapshot();
   });
 
   it('Pressing "o" runs test in "only changed files" mode', () => {

packages/jest-cli/src/watch.js

@@ -195,7 +195,7 @@ const usage = (
     chalk.dim(' \u203A Press ') + 'Enter' + chalk.dim(' to trigger a test run.'),
   ];
   /* eslint-enable max-len */
-  return messages.filter(message => !!message).join(delimiter);
+  return messages.filter(message => !!message).join(delimiter) + '\n';
 };
 
 module.exports = watch;