Fix regression: auto completion text cursor problem in Q3FileDialog

This was another regression in QLineEdit introduced with the move to QLineControl

setCursorPosition clear the selection, and setSelection move the cursor position.
So the case where we want the position at the beginning of the selection need
to be handled separately (by doing the selection reverse)

This does not cover the case where the position is in the middle, or outside
the selection, but it is not possible to do.

Task-number: QTBUG-10019
Reviewed-by: jbache

3 files changed, 42 insertions, 2 deletions

diff --git a/src/gui/widgets/qlineedit.cpp b/src/gui/widgets/qlineedit.cpp
index 2d2df92..f041a36 100644
--- a/src/gui/widgets/qlineedit.cpp
+++ b/src/gui/widgets/qlineedit.cpp
@@ -738,8 +738,14 @@ bool QLineEdit::validateAndSet(const QString &newText, int newPos,
         setText(oldText);
         return false;
     }
-    setCursorPosition(newPos);
-    setSelection(qMin(newMarkAnchor, newMarkDrag), qAbs(newMarkAnchor - newMarkDrag));
+    int selstart = qMin(newMarkAnchor, newMarkDrag);
+    int sellength = qAbs(newMarkAnchor - newMarkDrag);
+    if (selstart == newPos) {
+        selstart = qMax(newMarkAnchor, newMarkDrag);
+        sellength = -sellength;
+    }
+    //setSelection also set the position
+    setSelection(selstart, sellength);
     return true;
 }
 #endif //QT3_SUPPORT
diff --git a/tests/auto/qlineedit/qlineedit.pro b/tests/auto/qlineedit/qlineedit.pro
index f00a2d8..88527ce 100644
--- a/tests/auto/qlineedit/qlineedit.pro
+++ b/tests/auto/qlineedit/qlineedit.pro
@@ -1,4 +1,5 @@
 load(qttest_p4)
+QT += qt3support
 SOURCES  += tst_qlineedit.cpp
 
 
diff --git a/tests/auto/qlineedit/tst_qlineedit.cpp b/tests/auto/qlineedit/tst_qlineedit.cpp
index ca84b38..592c1cb 100644
--- a/tests/auto/qlineedit/tst_qlineedit.cpp
+++ b/tests/auto/qlineedit/tst_qlineedit.cpp
@@ -273,6 +273,11 @@ private slots:
     void taskQTBUG_4679_selectToStartEndOfBlock();
     void taskQTBUG_7395_readOnlyShortcut();
 
+#ifdef QT3_SUPPORT
+    void validateAndSet_data();
+    void validateAndSet();
+#endif
+
 protected slots:
 #ifdef QT3_SUPPORT
     void lostFocus();
@@ -1488,6 +1493,34 @@ void tst_QLineEdit::lostFocus()
 {
     editingFinished();
 }
+
+void tst_QLineEdit::validateAndSet_data()
+{
+    QTest::addColumn<QString>("newText");
+    QTest::addColumn<int>("newPos");
+    QTest::addColumn<int>("newMarkAnchor");
+    QTest::addColumn<int>("newMarkDrag");
+
+    QTest::newRow("1") << QString("Hello World") << 3 << 3 << 5;
+    QTest::newRow("2") << QString("Hello World") << 5 << 3 << 5;
+}
+
+void tst_QLineEdit::validateAndSet()
+{
+    QFETCH(QString, newText);
+    QFETCH(int, newPos);
+    QFETCH(int, newMarkAnchor);
+    QFETCH(int, newMarkDrag);
+
+    QLineEdit e;
+    e.validateAndSet(newText, newPos, newMarkAnchor, newMarkDrag);
+    QCOMPARE(e.text(), newText);
+    QCOMPARE(e.cursorPosition(), newPos);
+    QCOMPARE(e.selectedText(), newText.mid(newMarkAnchor, newMarkDrag-newMarkAnchor));
+}
+
+
+
 #endif
 void tst_QLineEdit::editingFinished()
 {