From f10aaf7e7e063ffa29832223a241623a1c84333e Mon Sep 17 00:00:00 2001
From: Allen Hutchison <adh@google.com>
Date: Wed, 16 Apr 2025 16:53:56 -0700
Subject: [PATCH] fix: Suppress crash from unhandled 429 stream error via
 global handler Introduces a process.on('unhandledRejection') handler in
 src/gemini.ts as a workaround for an issue where 429 ClientErrors originating
 from the @google/genai library's sendMessageStream during iteration can cause
 an unhandled rejection, even when caught within local try/catch blocks in the
 application code (e.g., in processGeminiStream). The handler specifically
 identifies this known 429 ClientError based on its type and message content.
 If matched, it logs a warning indicating the known issue is being suppressed
 and prevents process.exit(1). Any other genuinely unhandled promise
 rejections will still be logged as critical errors and will terminate the
 application, maintaining default behavior for unexpected issues. This
 workaround mitigates a suspected library-internal problem related to error
 propagation during asynchronous stream iteration.

---
 packages/cli/src/gemini.ts | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/packages/cli/src/gemini.ts b/packages/cli/src/gemini.ts
index 449f5096..96d70f01 100644
--- a/packages/cli/src/gemini.ts
+++ b/packages/cli/src/gemini.ts
@@ -26,6 +26,39 @@ async function main() {
     render(React.createElement(App, { directory: targetDir }));
 }
 
+// --- Global Unhandled Rejection Handler ---
+process.on('unhandledRejection', (reason, promise) => {
+    // Check if this is the known 429 ClientError that sometimes escapes
+    // this is a workaround for a specific issue with the way we are calling gemini
+    // where a 429 error is thrown but not caught, causing an unhandled rejection
+    // TODO(adh): Remove this when the race condition is fixed
+    const isKnownEscaped429 = 
+        reason instanceof Error &&
+        reason.name === 'ClientError' &&
+        reason.message.includes('got status: 429');
+
+    if (isKnownEscaped429) {
+        // Log it differently and DON'T exit, as it's likely already handled visually
+        console.warn('-----------------------------------------');
+        console.warn('WORKAROUND: Suppressed known escaped 429 Unhandled Rejection.');
+        console.warn('-----------------------------------------');
+        console.warn('Reason:', reason);
+        // No process.exit(1);
+    } else {
+        // Log other unexpected unhandled rejections as critical errors
+        console.error('=========================================');
+        console.error('CRITICAL: Unhandled Promise Rejection!');
+        console.error('=========================================');
+        console.error('Reason:', reason);
+        console.error('Stack trace may follow:');
+        if (!(reason instanceof Error)) {
+            console.error(reason);
+        }
+        // Exit for genuinely unhandled errors
+        process.exit(1);
+    }
+});
+
 // --- Global Entry Point ---
 main().catch((error) => {
     console.error('An unexpected critical error occurred:');