Refactor validate pattern and get pattern info function (#2985)

* add validate pattern function and tests for that

* refactor get test path pattern info

packages/jest-cli/src/lib/__tests__/validatePattern-test.js

@@ -0,0 +1,38 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @emails oncall+jsinfra
+ */
+'use strict';
+
+const validatePattern = require('../validatePattern');
+
+describe('validate pattern function', () => {
+  it('without passed args returns true', () => {
+    const isValid = validatePattern();
+
+    expect(isValid).toBeTruthy();
+  });
+
+  it('returns true for empty pattern', () => {
+    const isValid = validatePattern('');
+
+    expect(isValid).toBeTruthy();
+  });
+
+  it('returns true for valid pattern', () => {
+    const isValid = validatePattern('abc+');
+
+    expect(isValid).toBeTruthy();
+  });
+
+  it('returns false for invalid pattern', () => {
+    const isValid = validatePattern('\\');
+
+    expect(isValid).toBeFalsy();
+  });
+});

packages/jest-cli/src/lib/getTestPathPatternInfo.js

@@ -0,0 +1,70 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @flow
+ */
+'use strict';
+
+import type {PatternInfo} from '../SearchSource';
+
+const {clearLine} = require('jest-util');
+const chalk = require('chalk');
+const validatePattern = require('./validatePattern');
+
+const DEFAULT_PATTERN_INFO = {
+  input: '',
+  shouldTreatInputAsPattern: false,
+  testPathPattern: '',
+};
+
+const showTestPathPatternError = (testPathPattern: string) => {
+  clearLine(process.stdout);
+
+  // eslint-disable-next-line max-len
+  console.log(chalk.red(`  Invalid testPattern ${testPathPattern} supplied. Running all tests instead.`));
+};
+
+module.exports = (argv: Object): PatternInfo => {
+  if (argv.onlyChanged) {
+    return {
+      input: '',
+      lastCommit: argv.lastCommit,
+      onlyChanged: true,
+      watch: argv.watch,
+    };
+  }
+
+  if (argv.testPathPattern) {
+    if (validatePattern(argv.testPathPattern)) {
+      return {
+        input: argv.testPathPattern,
+        shouldTreatInputAsPattern: true,
+        testPathPattern: argv.testPathPattern,
+      };
+    } else {
+      showTestPathPatternError(argv.testPathPattern);
+    }
+  }
+
+  if (argv._ && argv._.length) {
+    const testPathPattern = argv._.join('|');
+
+    if (validatePattern(testPathPattern)) {
+      return {
+        findRelatedTests: argv.findRelatedTests,
+        input: argv._.join(' '),
+        paths: argv._,
+        shouldTreatInputAsPattern: false,
+        testPathPattern,
+      };
+    } else {
+      showTestPathPatternError(testPathPattern);
+    }
+  }
+
+  return DEFAULT_PATTERN_INFO;
+};

packages/jest-cli/src/lib/setState.js

@@ -9,7 +9,7 @@
  */
 'use strict';
 
-const buildTestPathPatternInfo = require('./buildTestPathPatternInfo');
+const getTestPathPatternInfo = require('./getTestPathPatternInfo');
 
 module.exports = (
   argv: Object,
@@ -40,7 +40,7 @@ module.exports = (
   }
 
   argv.onlyChanged = false;
-  argv.onlyChanged = buildTestPathPatternInfo(argv).input === ''
+  argv.onlyChanged = getTestPathPatternInfo(argv).input === ''
     && !argv.watchAll
     && !argv.testNamePattern;
 

packages/jest-cli/src/lib/validatePattern.js

@@ -0,0 +1,25 @@
+/**
+ * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @flow
+ */
+'use strict';
+
+const validatePattern = (pattern: string) => {
+  if (pattern) {
+    try {
+      // eslint-disable-next-line no-new
+      new RegExp(pattern, 'i');
+    } catch (e) {
+      return false;
+    }
+  }
+
+  return true;
+};
+
+module.exports = validatePattern;

packages/jest-cli/src/runJest.js

@@ -18,7 +18,7 @@ const fs = require('graceful-fs');
 const SearchSource = require('./SearchSource');
 const TestRunner = require('./TestRunner');
 
-const buildTestPathPatternInfo = require('./lib/buildTestPathPatternInfo');
+const getTestPathPatternInfo = require('./lib/getTestPathPatternInfo');
 const chalk = require('chalk');
 const {Console, formatTestResults} = require('jest-util');
 const getMaxWorkers = require('./lib/getMaxWorkers');
@@ -56,7 +56,7 @@ const runJest = (
 ) => {
   const maxWorkers = getMaxWorkers(argv);
   const localConsole = new Console(pipe, pipe);
-  let patternInfo = buildTestPathPatternInfo(argv);
+  let patternInfo = getTestPathPatternInfo(argv);
   return Promise.resolve().then(() => {
     const source = new SearchSource(hasteContext, config);
     return source.getTestPaths(patternInfo)
@@ -68,7 +68,7 @@ const runJest = (
               setState(argv, 'watchAll', {
                 noSCM: true,
               });
-              patternInfo = buildTestPathPatternInfo(argv);
+              patternInfo = getTestPathPatternInfo(argv);
               return source.getTestPaths(patternInfo);
             } else {
               localConsole.log(