Added module for test-utilities used across all packages

Summary: Added new package with test utilities re-used by other packages

Reviewed By: mweststrate

Differential Revision: D21949629

fbshipit-source-id: 8bfa959401669dc8911a1f647f417cafd92c2e4b

desktop/test-utils/src/consoleMock.ts

@@ -0,0 +1,39 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+/*
+ * mock-fs library has issues with calls to console.log in jest tests which are not resolved yet,
+ * so this console log can be used as a workaround in jest tests with fs-mocks:
+ *   const realConsole = global.console;
+ *   global.console = consoleMock as any;
+ *   afterAll(() => {
+ *     global.console = realConsole;
+ *   });
+ * See details: https://github.com/tschaub/mock-fs/issues/234
+ */
+
+function format(entry: any) {
+  if (typeof entry === 'object') {
+    try {
+      return JSON.stringify(entry);
+    } catch (e) {}
+  }
+
+  return entry;
+}
+
+function log(...msgs: any) {
+  process.stdout.write(msgs.map(format).join(' ') + '\n');
+}
+
+export default {
+  log,
+  warn: log,
+  error: log,
+};