File 0001-QDirIterator-don-t-crash-with-next-after-h... of Package qt6-base

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File 0001-QDirIterator-don-t-crash-with-next-after-hasNext-ret.patch of Package qt6-base

From 55a8050d1e762befeeb5ba557f458b0092cbb44b Mon Sep 17 00:00:00 2001
From: Ahmad Samir <a.samirh78@gmail.com>
Date: Wed, 16 Oct 2024 19:26:25 +0300
Subject: [PATCH] QDirIterator: don't crash with next() after hasNext()
 returned false

The typical use-case is calling hasNext() first before using next, but
the API docs say that calling next() even when hasNext() is false,
should just return an empty string.

[ChangeLog][QtCore][QDirIterator] Fixed a crash that happened if you
called next() after hasNext() had already returned false. Ideally you
should never call next() without first calling hasNext() as that could
lead to unexpected results (for example, infinite loops).

Fixes: QTBUG-130142
Change-Id: If0a8b1fe7dbd13b45793409a7a241e53c7257f24
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit c7691842f743f568a073582c8f0cacd6ee188f98)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/corelib/io/qdiriterator.cpp                       |  5 +++++
 .../auto/corelib/io/qdiriterator/tst_qdiriterator.cpp | 11 +++++++++++
 2 files changed, 16 insertions(+)

diff --git a/src/corelib/io/qdiriterator.cpp b/src/corelib/io/qdiriterator.cpp
index faea8088cb..7d7fe15684 100644
--- a/src/corelib/io/qdiriterator.cpp
+++ b/src/corelib/io/qdiriterator.cpp
@@ -103,6 +103,11 @@ public:
 
     void advance()
     {
+        // Match the behavior of advance() from before porting to QDirListing,
+        // that is, even if hasNext() returns false, calling next() returns an
+        // empty string without crashing. QTBUG-130142
+        if (it == lister.end())
+            return;
         currentFileInfo = nextFileInfo;
         if (++it != lister.end()) {
             nextFileInfo = it->fileInfo();
diff --git a/tests/auto/corelib/io/qdiriterator/tst_qdiriterator.cpp b/tests/auto/corelib/io/qdiriterator/tst_qdiriterator.cpp
index a0a8917c27..b739f0eb11 100644
--- a/tests/auto/corelib/io/qdiriterator/tst_qdiriterator.cpp
+++ b/tests/auto/corelib/io/qdiriterator/tst_qdiriterator.cpp
@@ -86,6 +86,8 @@ private slots:
     void hiddenDirs_hiddenFiles();
 #endif
 
+    void hasNextFalseNoCrash();
+
 private:
     QSharedPointer<QTemporaryDir> m_dataDir;
 };
@@ -642,6 +644,15 @@ void tst_QDirIterator::hiddenDirs_hiddenFiles()
 }
 #endif // Q_OS_WIN
 
+void tst_QDirIterator::hasNextFalseNoCrash()
+{
+    QDirIterator iter(u"empty"_s, QDir::NoDotAndDotDot);
+    // QTBUG-130142
+    // No crash if you call next() after hasNext() returned false
+    QVERIFY(!iter.hasNext());
+    QVERIFY(iter.next().isEmpty());
+}
+
 QTEST_MAIN(tst_QDirIterator)
 
 #include "tst_qdiriterator.moc"
-- 
2.47.0

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File 0001-QDirIterator-don-t-crash-with-next-after-hasNext-ret.patch of Package qt6-base

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