stop search if is undefined

Author: emuraton

packages/jest-haste-map/src/crawlers/__tests__/node.test.js

@@ -217,4 +217,20 @@ describe('node crawler', () => {
       expect(data.files).toEqual({});
     });
   });
+
+  it('completes with undefined names', () => {
+    process.platform = 'win32';
+
+    nodeCrawl = require('../node');
+
+    const files = Object.create(null);
+    return nodeCrawl({
+      data: {files},
+      extensions: ['js'],
+      ignore: pearMatcher,
+      roots: ['/empty'],
+    }).then(data => {
+      expect(data.files).toEqual({});
+    });
+  });
 });

packages/jest-haste-map/src/crawlers/node.js

@@ -30,7 +30,10 @@ function find(
     activeCalls++;
     fs.readdir(directory, (err, names) => {
       activeCalls--;
-
+      if (!names) {
+        callback(result);
+        return;
+      }
       names.forEach(file => {
         file = path.join(directory, file);
         if (ignore(file)) {