flowtype integration_tests/utils.js (jestjs#4261)

integration_tests/utils.js

@@ -4,16 +4,21 @@
  * 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 {Path} from 'types/Config';
+
 const {spawnSync} = require('child_process');
 const fs = require('fs');
 const path = require('path');
 const mkdirp = require('mkdirp');
 const rimraf = require('rimraf');
 
-const run = (cmd, cwd) => {
+const run = (cmd: string, cwd?: Path) => {
   const args = cmd.split(/\s/).slice(1);
   const spawnOptions = {cwd};
   const result = spawnSync(cmd.split(/\s/)[0], args, spawnOptions);
@@ -24,7 +29,7 @@ const run = (cmd, cwd) => {
       STDOUT: ${result.stdout && result.stdout.toString()}
       STDERR: ${result.stderr && result.stderr.toString()}
       STATUS: ${result.status}
-      ERROR: ${result.error}
+      ERROR: ${result.error && result.error.toString()}
     `;
     throw new Error(message);
   }
@@ -35,15 +40,15 @@ const run = (cmd, cwd) => {
   return result;
 };
 
-const linkJestPackage = (packageName, cwd) => {
+const linkJestPackage = (packageName: string, cwd: Path) => {
   const packagesDir = path.resolve(__dirname, '../packages');
   const packagePath = path.resolve(packagesDir, packageName);
   const destination = path.resolve(cwd, 'node_modules/');
   run(`mkdir -p ${destination}`);
   return run(`ln -sf ${packagePath} ${destination}`);
 };
 
-const fileExists = filePath => {
+const fileExists = (filePath: Path) => {
   try {
     fs.accessSync(filePath, fs.F_OK);
     return true;
@@ -52,9 +57,12 @@ const fileExists = filePath => {
   }
 };
 
-const makeTemplate = string => {
-  return values => {
-    return string.replace(/\$(\d+)/g, (match, number) => {
+const makeTemplate = (str: string): ((values?: Array<any>) => string) => {
+  return (values: ?Array<any>) => {
+    return str.replace(/\$(\d+)/g, (match, number) => {
+      if (!Array.isArray(values)) {
+        throw new Error('Array of values must be passed to the template.');
+      }
       return values[number - 1];
     });
   };
@@ -102,7 +110,10 @@ const copyDir = (src: string, dest: string) => {
   }
 };
 
-const createEmptyPackage = (directory, packageJson) => {
+const createEmptyPackage = (
+  directory: Path,
+  packageJson?: {[keys: string]: any},
+) => {
   const DEFAULT_PACKAGE_JSON = {
     description: 'THIS IS AN AUTOGENERATED FILE AND SHOULD NOT BE ADDED TO GIT',
     jest: {
@@ -118,7 +129,7 @@ const createEmptyPackage = (directory, packageJson) => {
   );
 };
 
-const extractSummary = stdout => {
+const extractSummary = (stdout: string) => {
   const match = stdout.match(
     /Test Suites:.*\nTests.*\nSnapshots.*\nTime.*(\nRan all test suites)*.*\n*$/gm,
   );