QmlProject: Don't use RegExp for simple wildcard matching

QRegExp matching is quite expensive, and has to be done for every file
in the project directory tree against all possible suffixes. Optimize
for the common case that the pattern is "*.suffix" by doing a
fileName.endsWidth(suffix) in this case.

This speeds up loading of examples/declarative/declarative.qmlproject by
about 30%.

Reviewed-by: Christian Kamm

src/plugins/qmlprojectmanager/fileformat/filefilteritems.cpp

@@ -47,7 +47,21 @@ void FileFilterBaseItem::setFilter(const QString &filter)
     m_filter = filter;
 
     m_regExpList.clear();
+    m_fileSuffixes.clear();
+
     foreach (const QString &pattern, filter.split(QLatin1Char(';'))) {
+        if (pattern.isEmpty())
+            continue;
+        // decide if it's a canonical pattern like *.x
+        if (pattern.startsWith(QLatin1String("*."))) {
+            const QString suffix = pattern.right(pattern.size() - 1);
+            if (!suffix.contains(QLatin1Char('*'))
+                    && !suffix.contains(QLatin1Char('?'))
+                    && !suffix.contains(QLatin1Char('['))) {
+                m_fileSuffixes << suffix;
+                continue;
+            }
+        }
         m_regExpList << QRegExp(pattern, Qt::CaseInsensitive, QRegExp::Wildcard);
     }
 
@@ -113,16 +127,9 @@ bool FileFilterBaseItem::matchesFile(const QString &filePath) const
             return true;
     }
 
-    bool regexMatches = false;
     const QString &fileName = QFileInfo(filePath).fileName();
-    foreach (const QRegExp &exp, m_regExpList) {
-        if (exp.exactMatch(fileName)) {
-            regexMatches = true;
-            break;
-        }
-    }
 
-    if (!regexMatches)
+    if (!fileMatches(fileName))
         return false;
 
     const QDir fileDir = QFileInfo(filePath).absoluteDir();
@@ -164,7 +171,7 @@ void FileFilterBaseItem::updateFileList()
     foreach (const QString &explicitPath, m_explicitFiles) {
         newFiles << absolutePath(explicitPath);
     }
-    if (!m_regExpList.isEmpty() && m_explicitFiles.isEmpty())
+    if ((!m_fileSuffixes.isEmpty() || !m_regExpList.isEmpty()) && m_explicitFiles.isEmpty())
         newFiles += filesInSubTree(QDir(m_defaultDir), QDir(projectDir), &dirsToBeWatched);
 
     if (newFiles != m_files) {
@@ -190,6 +197,23 @@ void FileFilterBaseItem::updateFileList()
         m_dirWatcher.addDirectories(watchDirs.toList());
 }
 
+bool FileFilterBaseItem::fileMatches(const QString &fileName) const
+{
+    foreach (const QString &suffix, m_fileSuffixes) {
+        if (fileName.endsWith(suffix, Qt::CaseInsensitive)) {
+            return true;
+        }
+    }
+
+    foreach (const QRegExp &filter, m_regExpList) {
+        if (filter.exactMatch(fileName)) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
 QSet<QString> FileFilterBaseItem::filesInSubTree(const QDir &rootDir, const QDir &dir, QSet<QString> *parsedDirs)
 {
     QSet<QString> fileSet;
@@ -199,12 +223,9 @@ QSet<QString> FileFilterBaseItem::filesInSubTree(const QDir &rootDir, const QDir
 
     foreach (const QFileInfo &file, dir.entryInfoList(QDir::Files)) {
         const QString fileName = file.fileName();
-        foreach (const QRegExp &filter, m_regExpList) {
-            if (filter.exactMatch(fileName)) {
-                fileSet.insert(file.absoluteFilePath());
-                break;
-            }
-        }
+
+        if (fileMatches(fileName))
+            fileSet.insert(file.absoluteFilePath());
     }
 
     if (recursive()) {

src/plugins/qmlprojectmanager/fileformat/filefilteritems.h

@@ -54,12 +54,15 @@ private:
     QString absolutePath(const QString &path) const;
     QString absoluteDir() const;
 
+    bool fileMatches(const QString &fileName) const;
     QSet<QString> filesInSubTree(const QDir &rootDir, const QDir &dir, QSet<QString> *parsedDirs = 0);
 
     QString m_rootDir;
     QString m_defaultDir;
 
     QString m_filter;
+    // simple "*.png" patterns are stored in m_fileSuffixes, otherwise store in m_regExpList
+    QList<QString> m_fileSuffixes;
     QList<QRegExp> m_regExpList;
 
     enum RecursiveOption {