From ea92f157ff58ec058ca6cb497a4b9bb9ce253e5e Mon Sep 17 00:00:00 2001
From: Robin Genz <mail@robingenz.dev>
Date: Wed, 21 Oct 2026 07:56:53 +0200
Subject: [PATCH] fix(apps:liveupdates:upload): report files that vanish while
 zipping as user error

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
---
 src/utils/file.ts     |  7 +++++--
 src/utils/zip.test.ts | 37 +++++++++++++++++++++++++++++++++++++
 src/utils/zip.ts      | 20 +++++++++++++++++++-
 3 files changed, 61 insertions(+), 3 deletions(-)
 create mode 100644 src/utils/zip.test.ts

diff --git a/src/utils/file.ts b/src/utils/file.ts
index 08ecd13..b718db9 100644
--- a/src/utils/file.ts
+++ b/src/utils/file.ts
@@ -4,7 +4,7 @@ import pathModule from 'path';
 import { createBufferFromPath } from './buffer.js';
 import { getCodeFromUnknownError, UserError } from './error.js';
 
-const concurrentModificationHint =
+export const concurrentModificationHint =
   'Make sure that no other process (e.g. a build or file sync client) modifies the folder while the command is running.';
 const readPermissionHint = 'Make sure that you have permission to read the file.';
 const writePermissionHint = 'Make sure that you have permission to write to the folder or choose a different path.';
@@ -65,12 +65,15 @@ export const readFileFromDirectory = async (path: string): Promise<Buffer> => {
     const code = getCodeFromUnknownError(error);
     const hint = code ? unreadableFileErrorHints[code] : undefined;
     if (hint) {
-      throw new UserError(`The file could not be read: ${path}. ${hint}`);
+      throw createUnreadableFileError(path, hint);
     }
     throw error;
   }
 };
 
+export const createUnreadableFileError = (path: string, hint: string): UserError =>
+  new UserError(`The file could not be read: ${path}. ${hint}`);
+
 export const directoryContainsSymlinks = async (path: string): Promise<boolean> => {
   const dirEntries = await fs.promises.readdir(path, { withFileTypes: true, recursive: true }).catch(() => []);
   return dirEntries.some((dirEntry) => dirEntry.isSymbolicLink());
diff --git a/src/utils/zip.test.ts b/src/utils/zip.test.ts
new file mode 100644
index 0000000..31653bb
--- /dev/null
+++ b/src/utils/zip.test.ts
@@ -0,0 +1,37 @@
+import { describe, expect, it, vi } from 'vitest';
+import { UserError } from './error.js';
+import zip from './zip.js';
+
+const { mockAddLocalFolder } = vi.hoisted(() => ({ mockAddLocalFolder: vi.fn() }));
+
+vi.mock('adm-zip', () => ({
+  default: function () {
+    return { addLocalFolder: mockAddLocalFolder, getEntries: () => [], toBuffer: () => Buffer.alloc(0) };
+  },
+}));
+
+describe('zipFolder', () => {
+  it('should throw a user error if a file vanished while zipping', async () => {
+    mockAddLocalFolder.mockImplementationOnce(() => {
+      throw new Error('ADM-ZIP: File not found: "www/index.html"');
+    });
+
+    const promise = zip.zipFolder('www');
+
+    await expect(promise).rejects.toThrow(UserError);
+    await expect(promise).rejects.toThrow(
+      'The file could not be read: www/index.html. Make sure that no other process',
+    );
+  });
+
+  it('should rethrow other errors', async () => {
+    mockAddLocalFolder.mockImplementationOnce(() => {
+      throw new Error('ADM-ZIP: Invalid filename');
+    });
+
+    const promise = zip.zipFolder('www');
+
+    await expect(promise).rejects.not.toThrow(UserError);
+    await expect(promise).rejects.toThrow('ADM-ZIP: Invalid filename');
+  });
+});
diff --git a/src/utils/zip.ts b/src/utils/zip.ts
index c5a7baa..6cb977c 100644
--- a/src/utils/zip.ts
+++ b/src/utils/zip.ts
@@ -1,4 +1,5 @@
 import { UserError } from '@/utils/error.js';
+import { concurrentModificationHint, createUnreadableFileError } from '@/utils/file.js';
 import AdmZip from 'adm-zip';
 import { globby } from 'globby';
 import path from 'path';
@@ -20,7 +21,15 @@ class ZipImpl implements Zip {
 
   async zipFolder(sourceFolder: string): Promise<Buffer> {
     const zip = new AdmZip();
-    zip.addLocalFolder(sourceFolder);
+    try {
+      zip.addLocalFolder(sourceFolder);
+    } catch (error) {
+      const vanishedFilePath = getVanishedFilePath(error);
+      if (vanishedFilePath) {
+        throw createUnreadableFileError(vanishedFilePath, concurrentModificationHint);
+      }
+      throw error;
+    }
     // Strip external file attributes from every entry. `addLocalFolder` copies
     // the source's Unix mode bits onto each entry, so a directory with e.g.
     // `0500` on a CI checkout ends up in the bundle and makes `zip4j` on
@@ -75,6 +84,15 @@ class ZipImpl implements Zip {
   }
 }
 
+// adm-zip lists all files first and reads them afterwards. A file that was
+// deleted in between is reported with this message and without an error code.
+const getVanishedFilePath = (error: unknown): string | undefined => {
+  if (!(error instanceof Error)) {
+    return undefined;
+  }
+  return error.message.match(/^ADM-ZIP: File not found: "(.+)"$/)?.[1];
+};
+
 const zip: Zip = new ZipImpl();
 
 export default zip;