[stable-4.0] fix(filesystem): deal with win32 long paths when recursively removing folders

src/libsync/filesystem.cpp

@@ -252,7 +252,7 @@
 }
 
 // Code inspired from Qt5's QDir::removeRecursively
 bool FileSystem::removeRecursively(const QString &path,
                                    const std::function<void(const QString &path, bool isDir)> &onDeleted,
                                    QStringList *errors,
                                    const std::function<void(const QString &path, bool isDir)> &onError,
@@ -312,7 +312,13 @@
         auto folderDeleteError = QString{};
 
         try {
-            if (!std::filesystem::remove(std::filesystem::path{fileInfo.filePath().toStdWString()})) {
+#ifdef Q_OS_WIN
+            // std::filesystem::remove does not handle paths greater than MAX_PATH, but it seems to be fine with the prefixed UNC paths ...
+            const auto fspath = std::filesystem::path{FileSystem::longWinPath(fileInfo.filePath()).toStdWString()};
+#else
+            const auto fspath = std::filesystem::path{fileInfo.filePath().toStdWString()};
+#endif
+            if (!std::filesystem::remove(fspath)) {
                 qCWarning(lcFileSystem()) << "File is already deleted" << fileInfo.filePath();
             }
         }

test/testfilesystem.cpp

@@ -7,7 +7,7 @@
  * any purpose.
  */
 
 #include <QtTest>
 #include <QTemporaryDir>
 #include <QTemporaryFile>
 
@@ -320,6 +320,28 @@
         QCOMPARE_EQ(aclSizeAfterReadWrite.AclBytesInUse, aclSizeInitial.AclBytesInUse);
     }
 #endif
+
+    void testRecursiveDeletionLongPaths()
+    {
+        QTemporaryDir tempDir;
+        QDir tempQDir{tempDir.path()};
+
+        const auto makeLongPathSegment = [](const QString &base) -> QString {
+            QString baseSegment = base + " ";
+            return baseSegment + QString("0").repeated(200 - baseSegment.size());
+        };
+
+        tempQDir.mkpath("Folder 1 - short name but long single subfolder/" + makeLongPathSegment("Subfolder without accentued characters - padding"));
+        tempQDir.mkpath(makeLongPathSegment("Folder 2 - directly a very long name"));
+        auto folder3Path = u"Folder 3 - short name but long multiples subfolder"_s;
+        for (auto i = 0; i < 5; i++) {
+            folder3Path.append("/subfolder %1 - total length 40 characters"_L1.arg(QString::number(i + 1)));
+        }
+        tempQDir.mkpath(folder3Path);
+        tempQDir.mkpath("Folder 4 - short name");
+
+        QVERIFY(FileSystem::removeRecursively(tempDir.path()));
+    }
 };
 
 QTEST_GUILESS_MAIN(TestFileSystem)