From d9463eb030537099c6bcecd4041fa8edcdc09c0a Mon Sep 17 00:00:00 2001
From: rory <rory@expensify.com>
Date: Fri, 21 Aug 2026 23:07:52 -0700
Subject: [PATCH 1/2] fix: stringify thrown errors in logAlert

Raw Error interpolation becomes [object Object] in some runtimes.
Use message/String so merge and subscriber failures stay readable.
---
 lib/Onyx.ts                  |  2 +-
 lib/OnyxConnectionManager.ts |  2 +-
 lib/OnyxUtils.ts             | 10 +++++++---
 3 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/lib/Onyx.ts b/lib/Onyx.ts
index 4356ec36d..211a9d49b 100644
--- a/lib/Onyx.ts
+++ b/lib/Onyx.ts
@@ -301,7 +301,7 @@ function merge<TKey extends OnyxKey>(key: TKey, changes: OnyxMergeInput<TKey>):
                     OnyxUtils.sendActionToDevTools(OnyxUtils.METHOD.MERGE, key, changes, mergedValue);
                 });
             } catch (error) {
-                Logger.logAlert(`An error occurred while applying merge for key: ${key}, Error: ${error}`);
+                Logger.logAlert(`An error occurred while applying merge for key: ${key}, Error: ${error instanceof Error ? error.message : String(error)}`);
                 return Promise.resolve();
             }
         });
diff --git a/lib/OnyxConnectionManager.ts b/lib/OnyxConnectionManager.ts
index 1eae1cdc5..ddf7ff00f 100644
--- a/lib/OnyxConnectionManager.ts
+++ b/lib/OnyxConnectionManager.ts
@@ -138,7 +138,7 @@ class OnyxConnectionManager {
                     (callback as DefaultConnectCallback<OnyxKey>)(connection.cachedCallbackValue, connection.cachedCallbackKey as OnyxKey);
                 }
             } catch (error) {
-                Logger.logAlert(`[ConnectionManager] Subscriber callback threw an error for key '${connection.onyxKey}': ${error}`);
+                Logger.logAlert(`[ConnectionManager] Subscriber callback threw an error for key '${connection.onyxKey}': ${String(error)}`);
             }
         }
     }
diff --git a/lib/OnyxUtils.ts b/lib/OnyxUtils.ts
index c4ac63f61..997db7efd 100644
--- a/lib/OnyxUtils.ts
+++ b/lib/OnyxUtils.ts
@@ -62,6 +62,10 @@ function resetDiskPressureLogThrottle(): void {
     lastDiskPressureLogTime = 0;
 }
 
+function formatCaughtError(error: unknown): string {
+    return error instanceof Error ? error.message : String(error);
+}
+
 type OnyxMethod = ValueOf<typeof METHOD>;
 
 /** Result of `prepareKeyValuePairsForStorage`: pairs to write and keys whose `null` value marks them for removal. */
@@ -598,7 +602,7 @@ function keysChanged<TKey extends CollectionKeyBase>(
             lastConnectionCallbackData.set(subscriber.subscriptionID, {value: cachedCollection, matchedKey: subscriber.key});
             subscriber.callback(cachedCollection, subscriber.key);
         } catch (error) {
-            Logger.logAlert(`[OnyxUtils.keysChanged] Subscriber callback threw an error for key '${collectionKey}': ${error}`);
+            Logger.logAlert(`[OnyxUtils.keysChanged] Subscriber callback threw an error for key '${collectionKey}': ${formatCaughtError(error)}`);
         }
     }
 
@@ -621,7 +625,7 @@ function keysChanged<TKey extends CollectionKeyBase>(
                 matchedKey: subscriber.key,
             });
         } catch (error) {
-            Logger.logAlert(`[OnyxUtils.keysChanged] Subscriber callback threw an error for key '${collectionKey}': ${error}`);
+            Logger.logAlert(`[OnyxUtils.keysChanged] Subscriber callback threw an error for key '${collectionKey}': ${formatCaughtError(error)}`);
         }
     }
 }
@@ -694,7 +698,7 @@ function keyChanged<TKey extends OnyxKey>(key: TKey, value: OnyxValue<TKey>, can
                 });
                 continue;
             } catch (error) {
-                Logger.logAlert(`[OnyxUtils.keyChanged] Subscriber callback threw an error for key '${key}': ${error}`);
+                Logger.logAlert(`[OnyxUtils.keyChanged] Subscriber callback threw an error for key '${key}': ${formatCaughtError(error)}`);
             }
 
             continue;

From 0a47b4ab308424c1b5681e7161da40dbdd9b7b5c Mon Sep 17 00:00:00 2001
From: rory <rory@expensify.com>
Date: Fri, 21 Aug 2026 23:29:46 -0700
Subject: [PATCH 2/2] fix: keep error name in formatCaughtError

error.message is empty for new TypeError() and drops TypeError /
custom names. toString() matches the old interpolation.
---
 lib/Onyx.ts      | 2 +-
 lib/OnyxUtils.ts | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/Onyx.ts b/lib/Onyx.ts
index 211a9d49b..29a1d20ab 100644
--- a/lib/Onyx.ts
+++ b/lib/Onyx.ts
@@ -301,7 +301,7 @@ function merge<TKey extends OnyxKey>(key: TKey, changes: OnyxMergeInput<TKey>):
                     OnyxUtils.sendActionToDevTools(OnyxUtils.METHOD.MERGE, key, changes, mergedValue);
                 });
             } catch (error) {
-                Logger.logAlert(`An error occurred while applying merge for key: ${key}, Error: ${error instanceof Error ? error.message : String(error)}`);
+                Logger.logAlert(`An error occurred while applying merge for key: ${key}, Error: ${error instanceof Error ? error.toString() : String(error)}`);
                 return Promise.resolve();
             }
         });
diff --git a/lib/OnyxUtils.ts b/lib/OnyxUtils.ts
index 997db7efd..519a1d8dc 100644
--- a/lib/OnyxUtils.ts
+++ b/lib/OnyxUtils.ts
@@ -63,7 +63,7 @@ function resetDiskPressureLogThrottle(): void {
 }
 
 function formatCaughtError(error: unknown): string {
-    return error instanceof Error ? error.message : String(error);
+    return error instanceof Error ? error.toString() : String(error);
 }
 
 type OnyxMethod = ValueOf<typeof METHOD>;