Do not put cursor at non-stop character positions

When moving cursors, non-stop positions are skipped, however certain
input sequences can still lead us there. In such cases we should
simply ignore those positions in cursorToX.

Task-number: QTBUG-7076
Reviewed-by: Eskil

2 files changed, 18 insertions, 0 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index 4595ef5..c92e15b 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -2507,6 +2507,9 @@ qreal QTextLine::cursorToX(int *cursorPos, Edge edge) const
 
     int pos = *cursorPos;
     int itm;
+    const HB_CharAttributes *attributes = eng->attributes();
+    while (pos < line.from + line.length && !attributes[pos].charStop)
+        pos++;
     if (pos == line.from + (int)line.length) {
         // end of line ensure we have the last item on the line
         itm = eng->findItem(pos-1);
diff --git a/tests/auto/qtextlayout/tst_qtextlayout.cpp b/tests/auto/qtextlayout/tst_qtextlayout.cpp
index 2414ab3..6c989ac 100644
--- a/tests/auto/qtextlayout/tst_qtextlayout.cpp
+++ b/tests/auto/qtextlayout/tst_qtextlayout.cpp
@@ -129,6 +129,7 @@ private slots:
     void textWidthWithLineSeparator();
     void cursorInLigatureWithMultipleLines();
     void xToCursorForLigatures();
+    void cursorInNonStopChars();
 
 private:
     QFont testFont;
@@ -1502,5 +1503,19 @@ void tst_QTextLayout::xToCursorForLigatures()
             line.xToCursor(width) == line.xToCursor(width / 2));
 }
 
+void tst_QTextLayout::cursorInNonStopChars()
+{
+#if defined(Q_WS_MAC)
+    QSKIP("This test can not be run on Mac", SkipAll);
+#endif
+    QTextLayout layout(QString::fromUtf8("\u0924\u094d\u0928"));
+    layout.beginLayout();
+    QTextLine line = layout.createLine();
+    layout.endLayout();
+
+    QVERIFY(line.cursorToX(1) == line.cursorToX(3));
+    QVERIFY(line.cursorToX(2) == line.cursorToX(3));
+}
+
 QTEST_MAIN(tst_QTextLayout)
 #include "tst_qtextlayout.moc"