VCS: Improve performance of isVcsFileOrDirectory implementations

FilePath operations are relative expensive on Windows compared to the
cost of a string comparison, so always first check the file name before
checking any file meta data.

Change-Id: Ibb4c13d7e11e0c01bdf3706a62362f4c0a27d284
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/bazaar/bazaarclient.cpp

@@ -147,8 +147,8 @@ void BazaarClient::annotate(const Utils::FilePath &workingDir, const QString &fi
 
 bool BazaarClient::isVcsDirectory(const FilePath &filePath) const
 {
-    return filePath.isDir()
+    return !filePath.fileName().compare(Constants::BAZAARREPO, HostOsInfo::fileNameCaseSensitivity())
-            && !filePath.fileName().compare(Constants::BAZAARREPO, HostOsInfo::fileNameCaseSensitivity());
+           && filePath.isDir();
 }
 
 FilePath BazaarClient::findTopLevelForFile(const FilePath &file) const

src/plugins/cvs/cvsplugin.cpp

@@ -333,8 +333,8 @@ Utils::Id CvsPluginPrivate::id() const
 
 bool CvsPluginPrivate::isVcsFileOrDirectory(const Utils::FilePath &filePath) const
 {
-    return filePath.isDir()
+    return !filePath.fileName().compare("CVS", Utils::HostOsInfo::fileNameCaseSensitivity())
-            && !filePath.fileName().compare("CVS", Utils::HostOsInfo::fileNameCaseSensitivity());
+           && filePath.isDir();
 }
 
 bool CvsPluginPrivate::isConfigured() const

src/plugins/fossil/fossilclient.cpp

@@ -742,9 +742,8 @@ void FossilClient::annotate(const FilePath &workingDir, const QString &file, int
 bool FossilClient::isVcsFileOrDirectory(const FilePath &filePath) const
 {
     // false for any dir or file other than fossil checkout db-file
-    return filePath.toFileInfo().isFile()
+    return !filePath.fileName().compare(Constants::FOSSILREPO, HostOsInfo::fileNameCaseSensitivity())
-           && !filePath.fileName().compare(Constants::FOSSILREPO,
+           && filePath.isFile();
-                                           HostOsInfo::fileNameCaseSensitivity());
 }
 
 FilePath FossilClient::findTopLevelForFile(const FilePath &file) const

src/plugins/mercurial/mercurialclient.cpp

@@ -347,8 +347,9 @@ void MercurialClient::revertAll(const FilePath &workingDir, const QString &revis
 
 bool MercurialClient::isVcsDirectory(const FilePath &filePath) const
 {
-    return filePath.isDir()
+    return !filePath.fileName()
-            && !filePath.fileName().compare(Constants::MERCURIALREPO, HostOsInfo::fileNameCaseSensitivity());
+                .compare(Constants::MERCURIALREPO, HostOsInfo::fileNameCaseSensitivity())
+           && filePath.isDir();
 }
 
 void MercurialClient::view(const FilePath &source, const QString &id,

src/plugins/subversion/subversionplugin.cpp

@@ -477,9 +477,9 @@ SubversionPluginPrivate::SubversionPluginPrivate()
 bool SubversionPluginPrivate::isVcsDirectory(const FilePath &fileName) const
 {
     const QString baseName = fileName.fileName();
-    return fileName.isDir() && contains(m_svnDirectories, [baseName](const QString &s) {
+    return contains(m_svnDirectories, [baseName](const QString &s) {
         return !baseName.compare(s, HostOsInfo::fileNameCaseSensitivity());
-    });
+    }) && fileName.isDir();
 }
 
 bool SubversionPluginPrivate::activateCommit()