Windows watch mode fix (jestjs#3563)

* Fix interactive watch arrow selection on Windows jestjs#3516

* Refactored fix for jestjs#3516 to use replacePathSepForRegex

* Fixed the failing test on Windows for the jestjs#3516 fix

* Bump regex-slash to 1.0.1 (provides a flow lib def)

* Update watch-filename-pattern-mode-test.js

* Code review feedback

* Fixed lint errors and implemented PR feedback

* Revert yarn.lock changes

packages/jest-cli/src/__tests__/watch-filename-pattern-mode-test.js

@@ -145,6 +145,8 @@ describe('Watch mode flows', () => {
   });
 
   it('can select a specific file name from the typeahead results', () => {
+    const toUnixPathPattern = pathPattern => pathPattern.replace(/\\\\/g, '/');
+
     contexts[0].config = {rootDir: ''};
     watch(globalConfig, contexts, argv, pipe, hasteMapInstances, stdin);
 
@@ -164,7 +166,7 @@ describe('Watch mode flows', () => {
 
     stdin.emit(KEYS.ENTER);
 
-    expect(argv.testPathPattern).toMatchSnapshot();
+    expect(toUnixPathPattern(argv.testPathPattern)).toMatchSnapshot();
   });
 
   it('Results in pattern mode get truncated appropriately', () => {

packages/jest-cli/src/watch.js

@@ -14,11 +14,12 @@ import type {Context} from 'types/Context';
 
 const ansiEscapes = require('ansi-escapes');
 const chalk = require('chalk');
+const {replacePathSepForRegex} = require('jest-regex-util');
 const HasteMap = require('jest-haste-map');
 const isCI = require('is-ci');
-const createContext = require('./lib/createContext');
 const isValidPath = require('./lib/isValidPath');
 const preRunMessage = require('./preRunMessage');
+const createContext = require('./lib/createContext');
 const runJest = require('./runJest');
 const updateArgv = require('./lib/updateArgv');
 const SearchSource = require('./SearchSource');
@@ -201,7 +202,7 @@ const watch = (
           testPathPattern => {
             updateArgv(argv, 'watch', {
               testNamePattern: '',
-              testPathPattern,
+              testPathPattern: replacePathSepForRegex(testPathPattern),
             });
 
             startRun();