From 3bfdf8cef91a4778ce6d0ea38f613e0d1c52808f Mon Sep 17 00:00:00 2001
From: Linus Rath <139418639+rathlinus@users.noreply.github.com>
Date: Thu, 29 Oct 2026 03:19:43 +0100
Subject: [PATCH] fix: give a restored file with a clashing WebDAV name a free
 name the server accepts

---
 src/api/__tests__/files-trash.test.ts | 14 ++++++++++++++
 src/api/files-trash.ts                | 12 +++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/src/api/__tests__/files-trash.test.ts b/src/api/__tests__/files-trash.test.ts
index dcb29ea6..a927f340 100644
--- a/src/api/__tests__/files-trash.test.ts
+++ b/src/api/__tests__/files-trash.test.ts
@@ -96,6 +96,8 @@ function signIn(username: string, filesAccount = 'acc-1') {
 
 beforeEach(() => {
   signIn('me@example.org');
+  // No naming rules published unless a test says so.
+  (jmapClient.getAccountCapability as ReturnType<typeof vi.fn>).mockReturnValue(undefined);
   nextId = 1;
   calls = [];
   refuseUpdate = new Set();
@@ -309,6 +311,18 @@ describe('restoreFromTrash', () => {
     expect(byId('a')!.parentId).toBeNull();
   });
 
+  it('gives a clashing WebDAV name a free one the server accepts', async () => {
+    // Stored by WebDAV with a ":" escaped, which JMAP names refuse.
+    store.push({ id: 'w', parentId: 'docs', name: 'a%3Ab.txt', blobId: 'bw' });
+    await moveToTrash(listed(), listed().filter((n) => n.id === 'w'), 1730112000007);
+    store.push({ id: 'w2', parentId: 'docs', name: 'a%3Ab.txt', blobId: 'bw2' });
+    (jmapClient.getAccountCapability as ReturnType<typeof vi.fn>).mockReturnValue({ forbiddenNameChars: ':*' });
+    await restoreFromTrash(trashedItems(listed()));
+    const update = calls.filter((c) => c.update).pop()!.update as Record<string, Record<string, unknown>>;
+    expect(update.w).toEqual({ parentId: 'docs', name: 'a_b (1).txt' });
+    expect(byId('w')).toMatchObject({ parentId: 'docs', name: 'a_b (1).txt' });
+  });
+
   it('gives a folder named .Trash that goes back to the root another name', async () => {
     store.push({ id: 'x', parentId: 'docs', name: '.Trash', blobId: null }, { id: 'xin', parentId: 'x', name: 'in.txt', blobId: 'bi' });
     let nodes = listed();
diff --git a/src/api/files-trash.ts b/src/api/files-trash.ts
index 3bb15c15..23e32bef 100644
--- a/src/api/files-trash.ts
+++ b/src/api/files-trash.ts
@@ -1,11 +1,12 @@
 import type { FileNode } from './types';
 import { jmapClient } from './jmap-client';
 import {
-  createFolder, deleteFileNodes, destroyEmptyFolders, filesAccountId, getAllFileNodes, isCrossAccountId,
-  isFolder, updateFileNodes,
+  createFolder, deleteFileNodes, destroyEmptyFolders, filesAccountId, getAllFileNodes, getFileNameRules,
+  isCrossAccountId, isFolder, updateFileNodes,
 } from './files';
 import { JMAPSetError } from './jmap-result';
 import { getUniqueName } from '../lib/filenode-name';
+import { acceptedFileName } from '../lib/file-name-rules';
 import {
   TRASH_FOLDER_NAME, findTrashFolder, restoreTarget, trashBatchName, trashPlaces, trashSubtreeIds, trashedItems,
   type TrashedItem,
@@ -226,6 +227,7 @@ export async function restoreFromTrash(items: TrashedItem[], drive?: TrashDrive)
     }
     return null;
   };
+  const rules = getFileNameRules();
   const restored = new Set<string>();
   const tried = new Set<string>();
   const updates: Record<string, Partial<Pick<FileNode, 'name' | 'parentId'>>> = {};
@@ -249,7 +251,11 @@ export async function restoreFromTrash(items: TrashedItem[], drive?: TrashDrive)
         ? from
         : restoreTarget(item, places);
       const used = namesIn(target);
-      const name = getUniqueName(item.node.name, used);
+      let name = getUniqueName(item.node.name, used);
+      // A new name goes to the server as it is, so it must pass its rules: a
+      // WebDAV name lists decoded ("a%3Ab.txt" as "a:b.txt"), and the ":"
+      // in "a:b (1).txt" would be refused.
+      if (name !== item.node.name) name = getUniqueName(acceptedFileName(name, rules), used);
       used.add(name);
       // The name only goes along when it has to change: the listing shows a
       // WebDAV name decoded, and sending that back would rename the file.