File search: Avoid symlink loops and duplicate directories

Looks like this was always broken, but got more prominent by the
introduction of automatic directory locator filters for all open
projects.

Task-number: QTCREATORBUG-22662
Change-Id: I248fb611bb1a6226b27901ea6ab310fc640def7a
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>
Reviewed-by: David Schulz <david.schulz@qt.io>

2 files changed, 29 insertions, 16 deletions

diff --git a/src/libs/utils/filesearch.cpp b/src/libs/utils/filesearch.cpp
index 0bdf3991c5..03aa1cf9b2 100644
--- a/src/libs/utils/filesearch.cpp
+++ b/src/libs/utils/filesearch.cpp
@@ -651,11 +651,16 @@ SubDirFileIterator::SubDirFileIterator(const QStringList &directories, const QSt
 {
     m_encoding = (encoding == nullptr ? QTextCodec::codecForLocale() : encoding);
     qreal maxPer = qreal(MAX_PROGRESS) / directories.count();
-    foreach (const QString &directoryEntry, directories) {
+    for (const QString &directoryEntry : directories) {
         if (!directoryEntry.isEmpty()) {
-            m_dirs.push(QDir(directoryEntry));
-            m_progressValues.push(maxPer);
-            m_processedValues.push(false);
+            const QDir dir(directoryEntry);
+            const QString canonicalPath = dir.canonicalPath();
+            if (!canonicalPath.isEmpty() && dir.exists()) {
+                m_dirs.push(dir);
+                m_knownDirs.insert(canonicalPath);
+                m_progressValues.push(maxPer);
+                m_processedValues.push(false);
+            }
         }
     }
 }
@@ -676,10 +681,18 @@ void SubDirFileIterator::update(int index)
         const bool processed = m_processedValues.pop();
         if (dir.exists()) {
             const QString dirPath = dir.path();
-            QStringList subDirs;
-            if (!processed)
-                subDirs = dir.entryList(QDir::Dirs|QDir::Hidden|QDir::NoDotAndDotDot);
-            if (subDirs.isEmpty()) {
+            using Dir = QString;
+            using CanonicalDir = QString;
+            std::vector<std::pair<Dir, CanonicalDir>> subDirs;
+            if (!processed) {
+                for (const QFileInfo &info :
+                     dir.entryInfoList(QDir::Dirs | QDir::Hidden | QDir::NoDotAndDotDot)) {
+                    const QString canonicalDir = info.canonicalFilePath();
+                    if (!m_knownDirs.contains(canonicalDir))
+                        subDirs.emplace_back(info.filePath(), canonicalDir);
+                }
+            }
+            if (subDirs.empty()) {
                 const QStringList allFileEntries = dir.entryList(QDir::Files|QDir::Hidden);
                 const QStringList allFilePaths = Utils::transform(allFileEntries,
                                                                   [&dirPath](const QString &entry) {
@@ -696,14 +709,13 @@ void SubDirFileIterator::update(int index)
                 m_dirs.push(dir);
                 m_progressValues.push(subProgress);
                 m_processedValues.push(true);
-                QStringListIterator it(subDirs);
-                it.toBack();
-                while (it.hasPrevious()) {
-                    const QString &directory = it.previous();
-                    m_dirs.push(QDir(dirPath + QLatin1Char('/') + directory));
-                    m_progressValues.push(subProgress);
-                    m_processedValues.push(false);
-                }
+                Utils::reverseForeach(subDirs,
+                                      [this, subProgress](const std::pair<Dir, CanonicalDir> &dir) {
+                                          m_dirs.push(QDir(dir.first));
+                                          m_knownDirs.insert(dir.second);
+                                          m_progressValues.push(subProgress);
+                                          m_processedValues.push(false);
+                                      });
             }
         } else {
             m_progress += dirProgressMax;
diff --git a/src/libs/utils/filesearch.h b/src/libs/utils/filesearch.h
index cddb637184..546a7334cc 100644
--- a/src/libs/utils/filesearch.h
+++ b/src/libs/utils/filesearch.h
@@ -159,6 +159,7 @@ private:
     std::function<QStringList(const QStringList &)> m_filterFiles;
     QTextCodec *m_encoding;
     QStack<QDir> m_dirs;
+    QSet<QString> m_knownDirs;
     QStack<qreal> m_progressValues;
     QStack<bool> m_processedValues;
     qreal m_progress;