fix: keep the error message in logs when the stack omits it (#115)

php-worker.js

@@ -5,6 +5,7 @@ import {
 import {
   createPhpBridgeChannel,
   createShellChannel,
+  formatErrorDetail,
 } from "./src/shared/protocol.js";
 import {
   bootstrapNextcloud,
@@ -18,7 +19,6 @@ import {
   isEmscriptenNetworkError,
   isFatalWasmError,
   isSafeToReplay,
-  formatErrorDetail,
   createSnapshotManager,
   requestPathname,
 } from "./src/runtime/crash-recovery.js";

src/runtime/crash-recovery.js

@@ -102,29 +102,6 @@ export function requestPathname(request) {
   }
 }
 
-/**
- * Format an error into a human-readable string for display/logging.
- */
-export function formatErrorDetail(error) {
-  if (!error) {
-    return "Unknown error";
-  }
-
-  if (typeof error === "string") {
-    return error;
-  }
-
-  if (error instanceof Error) {
-    return String(error.stack || error.message || error);
-  }
-
-  try {
-    return JSON.stringify(error, null, 2);
-  } catch {
-    return String(error);
-  }
-}
-
 /**
  * Create a state snapshot manager for crash recovery.
  *

src/shared/protocol.js

@@ -13,3 +13,32 @@ export function createPhpBridgeChannel(scopeId) {
 export function createWorkerRequestId() {
   return globalThis.crypto.randomUUID();
 }
+
+/**
+ * Format an error into a human-readable string for display/logging.
+ */
+export function formatErrorDetail(error) {
+  if (!error) {
+    return "Unknown error";
+  }
+
+  if (typeof error === "string") {
+    return error;
+  }
+
+  if (error instanceof Error) {
+    // Chromium's stack starts with "Name: message"; Firefox and Safari list
+    // only the frames, so the message would be lost.
+    const head = `${error.name}: ${error.message}`;
+    if (!error.stack || error.stack.startsWith(head)) {
+      return String(error.stack || head);
+    }
+    return `${head}\n${error.stack}`.trim();
+  }
+
+  try {
+    return JSON.stringify(error, null, 2);
+  } catch {
+    return String(error);
+  }
+}

src/shell/main.js

@@ -24,7 +24,7 @@ import {
   hasBlueprintUrlOverride,
   resolveRemoteUrl,
 } from "../shared/paths.js";
-import { createShellChannel } from "../shared/protocol.js";
+import { createShellChannel, formatErrorDetail } from "../shared/protocol.js";
 import {
   createServiceWorkerUnsupportedError,
   isServiceWorkerSupported,
@@ -916,7 +916,7 @@ els.importInput.addEventListener("change", async () => {
     await importPayload(file);
     appendLog(`Imported configuration from ${file.name}`);
   } catch (error) {
-    appendLog(String(error?.stack || error?.message || error), true);
+    appendLog(formatErrorDetail(error), true);
   } finally {
     els.importInput.value = "";
   }
@@ -947,6 +947,6 @@ els.reset.addEventListener("click", () => {
 
 main().catch((error) => {
   setUiLocked(false);
-  appendLog(String(error?.stack || error?.message || error), true);
+  appendLog(formatErrorDetail(error), true);
   captureException(error, { source: "shell-main" });
 });

sw.js

@@ -1,5 +1,5 @@
 import { BUILD_VERSION } from "./src/generated/build-version.js";
-import { createPhpBridgeChannel, createWorkerRequestId } from "./src/shared/protocol.js";
+import { createPhpBridgeChannel, createWorkerRequestId, formatErrorDetail } from "./src/shared/protocol.js";
 import {
   buildSandboxedIframeCompatibilityScript,
   consumeSandboxCompatibility,
@@ -662,7 +662,7 @@ self.addEventListener("fetch", (event) => {
         serializedRequest: await buildForwardedRequest(event.request, forwardedUrl, bufferedBody),
         runtimeId,
         scopeId,
-      }).catch((error) => buildErrorResponse(String(error?.stack || error?.message || error)));
+      }).catch((error) => buildErrorResponse(formatErrorDetail(error)));
 
       if (isCacheableAssetResponse(requestPath, fresh)) {
         cache.put(url.toString(), fresh.clone()).catch(() => {});
@@ -675,7 +675,7 @@ self.addEventListener("fetch", (event) => {
       serializedRequest: await buildForwardedRequest(event.request, forwardedUrl, bufferedBody),
       runtimeId,
       scopeId,
-    }).catch((error) => buildErrorResponse(String(error?.stack || error?.message || error)));
+    }).catch((error) => buildErrorResponse(formatErrorDetail(error)));
 
     const locationScopedResponse = rewriteScopedLocation(response, {
       origin: url.origin,

tests/shared-protocol.test.mjs

@@ -0,0 +1,23 @@
+import assert from "node:assert/strict";
+import { test } from "node:test";
+
+import { formatErrorDetail } from "../src/shared/protocol.js";
+
+test("formatErrorDetail keeps the error message when the stack omits it", () => {
+  // Firefox and Safari: the stack has only frames, no "Name: message" line.
+  const firefox = new Error("needs what this installation lacks");
+  firefox.name = "PHPExecutionFailureError";
+  firefox.stack = "run@http://localhost/dist/php-worker.bundle.js:1:1\n";
+  assert.equal(
+    formatErrorDetail(firefox),
+    "PHPExecutionFailureError: needs what this installation lacks\nrun@http://localhost/dist/php-worker.bundle.js:1:1",
+  );
+
+  // Chromium: the stack already starts with "Name: message".
+  const chromium = new Error("boom");
+  assert.equal(formatErrorDetail(chromium), chromium.stack);
+
+  assert.equal(formatErrorDetail("plain"), "plain");
+  assert.equal(formatErrorDetail(null), "Unknown error");
+  assert.equal(formatErrorDetail({ a: 1 }), '{\n  "a": 1\n}');
+});