From f9f1d6026700566b3aadb035f1762ed92ef7707f Mon Sep 17 00:00:00 2001
From: Michel Weststrate <mweststrate@fb.com>
Date: Thu, 21 Nov 2019 06:28:24 -0800
Subject: [PATCH] Fix some DEV errors showing up as `DEV: [{}]`

Summary: Collections of errors were not reported correctly in the UI. Also, reporting errors could crash flipper if the error is not serializable (for example due to being cyclic).

Reviewed By: jknoxville

Differential Revision: D18595257

fbshipit-source-id: 689b6dbfe5d7daa6d84bd703dba9daa6be2e6b82
---
 src/utils/errors.tsx | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/utils/errors.tsx b/src/utils/errors.tsx
index 59240082c..de1cfd29a 100644
--- a/src/utils/errors.tsx
+++ b/src/utils/errors.tsx
@@ -13,12 +13,21 @@ export class CancelledPromiseError extends Error {
     this.name = 'CancelledPromiseError';
   }
 }
-export function getStringFromErrorLike(e: any) {
-  if (typeof e == 'string') {
+
+export function getStringFromErrorLike(e: any): string {
+  if (Array.isArray(e)) {
+    return e.map(getStringFromErrorLike).join(' ');
+  } else if (typeof e == 'string') {
     return e;
   } else if (e instanceof Error) {
-    return e.message;
+    return e.message || e.toString();
   } else {
-    return JSON.stringify(e);
+    try {
+      return JSON.stringify(e);
+    } catch (e) {
+      // Stringify might fail on arbitrary structures
+      // Last resort: toString it.
+      return '' + e;
+    }
   }
 }