From 78416e0ca4cf9d74c1a778fe448bc946a7ded8c2 Mon Sep 17 00:00:00 2001 From: Eskil Abrahamsen Blomfeldt Date: Thu, 5 Jan 2023 09:20:42 +0100 Subject: [PATCH] Fix infinite layout loop with negative line width Setting a negative line width does not make much sense, but in earlier Qt versions, this work the same as if the line width was 0 (just give you the minimal layout given wrapping constraints). But since 991c056438b311566bc4ea543af0f33dfd5dffbb, we check if current width > line width at an earlier point, and because 0 > -1, we would exit immediately before adding any characters to the text line. To restore the behavior in earlier versions, we set the minimum possible line width to 0. Fixes: QTBUG-109474 Change-Id: Iceadd5135681f61b30de8221853834983941c5a4 Reviewed-by: Lars Knoll Reviewed-by: hjk (cherry picked from commit 49a63d375972079ae3000c8b7d512d58d4de32bb) --- src/gui/text/qtextlayout.cpp | 5 +---- tests/auto/gui/text/qtextlayout/tst_qtextlayout.cpp | 12 ++++++++++++ 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp index aeee1652b8e..c6fd99e57cc 100644 --- a/src/gui/text/qtextlayout.cpp +++ b/src/gui/text/qtextlayout.cpp @@ -1612,10 +1612,7 @@ void QTextLine::setLineWidth(qreal width) return; } - if (width > QFIXED_MAX) - width = QFIXED_MAX; - - line.width = QFixed::fromReal(width); + line.width = QFixed::fromReal(qBound(0.0, width, qreal(QFIXED_MAX))); if (line.length && line.textWidth <= line.width && line.from + line.length == eng->layoutData->string.size()) diff --git a/tests/auto/gui/text/qtextlayout/tst_qtextlayout.cpp b/tests/auto/gui/text/qtextlayout/tst_qtextlayout.cpp index 9e6daf81b13..cf835fe245f 100644 --- a/tests/auto/gui/text/qtextlayout/tst_qtextlayout.cpp +++ b/tests/auto/gui/text/qtextlayout/tst_qtextlayout.cpp @@ -126,6 +126,7 @@ private slots: void softHyphens(); void min_maximumWidth_data(); void min_maximumWidth(); + void negativeLineWidth(); private: QFont testFont; @@ -2715,5 +2716,16 @@ void tst_QTextLayout::min_maximumWidth() } } +void tst_QTextLayout::negativeLineWidth() +{ + QTextLayout layout; + layout.setText("Foo bar"); + layout.beginLayout(); + QTextLine line = layout.createLine(); + line.setLineWidth(-1); + QVERIFY(line.textLength() > 0); + layout.endLayout(); +} + QTEST_MAIN(tst_QTextLayout) #include "tst_qtextlayout.moc"