Utils: Fake root info

When trying to open a FileDialog all roots were tested for existence.
This is slow and might show ask-pass.

Since "/" can be considered always valid, we create a fake entry for it
and only test existence of remote paths if they are not a root path.

In the future FilePath should get a "isRoot()" function so we don't just
test for == "/".

Remove the fileAccess from WebAssembly devices.

Change-Id: I7a1a6e7d2025e9fd4428e4bd1d07cdbdb5680c8e
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/libs/utils/devicefileaccess.cpp

@@ -829,6 +829,19 @@ QByteArray UnixDeviceFileAccess::fileId(const FilePath &filePath) const
 
 FilePathInfo UnixDeviceFileAccess::filePathInfo(const FilePath &filePath) const
 {
+    if (filePath.path() == "/") // TODO: Add FilePath::isRoot()
+    {
+        const FilePathInfo r{4096,
+                             FilePathInfo::FileFlags(
+                                 FilePathInfo::ReadOwnerPerm | FilePathInfo::WriteOwnerPerm
+                                 | FilePathInfo::ExeOwnerPerm | FilePathInfo::ReadGroupPerm
+                                 | FilePathInfo::ExeGroupPerm | FilePathInfo::ReadOtherPerm
+                                 | FilePathInfo::ExeOtherPerm | FilePathInfo::DirectoryType
+                                 | FilePathInfo::LocalDiskFlag | FilePathInfo::ExistsFlag),
+                             QDateTime::currentDateTime()};
+
+        return r;
+    }
     const RunResult stat = runInShell({"stat", {"-L", "-c", "%f %Y %s", filePath.path()}, OsType::OsTypeLinux});
     return FileUtils::filePathInfoFromTriple(QString::fromLatin1(stat.stdOut));
 }

src/libs/utils/fileutils.cpp

@@ -415,26 +415,30 @@ FilePath qUrlToFilePath(const QUrl &url)
 
 QUrl filePathToQUrl(const FilePath &filePath)
 {
-   return QUrl::fromLocalFile(filePath.toFSPathString());
+    return QUrl::fromLocalFile(filePath.toFSPathString());
 }
 
 void prepareNonNativeDialog(QFileDialog &dialog)
 {
+    const auto isValidSideBarPath = [](const FilePath &fp) {
+        return !fp.needsDevice() || fp.hasFileAccess();
+    };
+
     // Checking QFileDialog::itemDelegate() seems to be the only way to determine
     // whether the dialog is native or not.
     if (dialog.itemDelegate()) {
         FilePaths sideBarPaths;
 
-        // Check existing urls, remove paths that need a device and no longer exist.
+        // Check existing urls, remove paths that need a device and are no longer valid.
         for (const QUrl &url : dialog.sidebarUrls()) {
             FilePath path = qUrlToFilePath(url);
-            if (!path.needsDevice() || path.exists())
+            if (isValidSideBarPath(path))
                 sideBarPaths.append(path);
         }
 
-        // Add all device roots that are not already in the sidebar and exist.
+        // Add all device roots that are not already in the sidebar and valid.
         for (const FilePath &path : FSEngine::registeredDeviceRoots()) {
-            if (!sideBarPaths.contains(path) && path.exists())
+            if (!sideBarPaths.contains(path) && isValidSideBarPath(path))
                 sideBarPaths.append(path);
         }
 

src/libs/utils/fsengine/fsengine_impl.cpp

@@ -44,6 +44,9 @@ bool FSEngineImpl::open(QIODevice::OpenMode openMode)
                                                                           createCacheData);
     bool exists = (data.filePathInfo.fileFlags & QAbstractFileEngine::ExistsFlag);
 
+    if (data.filePathInfo.fileFlags & QAbstractFileEngine::DirectoryType)
+        return false;
+
     g_filePathInfoCache.invalidate(m_filePath);
 
     ensureStorage();

src/plugins/webassembly/webassemblydevice.cpp

@@ -23,6 +23,7 @@ WebAssemblyDevice::WebAssemblyDevice()
     setDeviceState(IDevice::DeviceStateUnknown);
     setMachineType(IDevice::Hardware);
     setOsType(OsTypeOther);
+    setFileAccess(nullptr);
 }
 
 IDevice::Ptr WebAssemblyDevice::create()