Editing: Delete last Vertex crashes QGIS

[qgib]

Author Name: bjpfei - (bjpfei -)
Original Redmine Issue: 6240
Affected QGIS version: 1.8.0
Redmine category:digitising

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When editing a polygon deleting the last vertex crashes QGIS when you delete another vertex.

1.) Start editing a polygon layer.
2.) Search the last vertex of the polygon and delete it.
3.) After deleting the vertex it's still visible (see Attachment)
4.) Delete another vertex.
5.) QGIS crashes

You can prevent QGIS from crashing when you click another tool (like zoom) before deleting the next vertex.
Here is the output of QGIS stacktrace.

_Fatal: ASSERT: "!mChangingGeometry" in file /usr/local/src/Quantum-GIS-1.8/src/app/nodetool/qgsselectedfeature.cpp, line 125
Stacktrace (run through c++filt):
/usr/local/qgis-1.8/bin/qgis(myMessageOutput(QtMsgType, char const*)+0x1a7)[0x52e3de]
/usr/lib/libQtCore.so.4(qt_message_output(QtMsgType, char const*)+0x1e)[0x7f7a34dbe7ee]
/usr/lib/libQtCore.so.4(+0x71a22)[0x7f7a34dbea22]
/usr/lib/libQtCore.so.4(qFatal(char const*, ...)+0x95)[0x7f7a34dbebd5]
/usr/local/qgis-1.8/bin/qgis(QgsSelectedFeature::beginGeometryChange()+0x31)[0x67bd1d]
/usr/local/qgis-1.8/bin/qgis(QgsSelectedFeature::deleteSelectedVertexes()+0x23d)[0x67c853]
/usr/local/qgis-1.8/bin/qgis(QgsMapToolNodeTool::keyReleaseEvent(QKeyEvent*)+0x72)[0x679552]
/usr/local/qgis-1.8/lib/libqgis_gui.so.1.8.0(QgsMapCanvas::keyReleaseEvent(QKeyEvent*)+0xda)[0x7f7a35a855b4]
/usr/lib/libQtGui.so.4(QWidget::event(QEvent*)+0x7b7)[0x7f7a342ca347]
/usr/lib/libQtGui.so.4(QFrame::event(QEvent*)+0x26)[0x7f7a346714e6]
/usr/lib/libQtGui.so.4(QAbstractScrollArea::event(QEvent*)+0xbb)[0x7f7a346fc8ab]
/usr/lib/libQtGui.so.4(QApplicationPrivate::notify_helper(QObject*, QEvent*)+0xac)[0x7f7a3427422c]
/usr/lib/libQtGui.so.4(QApplication::notify(QObject*, QEvent*)+0x1915)[0x7f7a3427bec5]
/usr/local/qgis-1.8/lib/libqgis_core.so.1.8.0(QgsApplication::notify(QObject*, QEvent*)+0xac)[0x7f7a35ff5e2a]
/usr/lib/libQtCore.so.4(QCoreApplication::notifyInternal(QObject*, QEvent*)+0x8c)[0x7f7a34ebb06c]
/usr/lib/libQtGui.so.4(+0x26916a)[0x7f7a3431f16a]
/usr/lib/libQtGui.so.4(+0x26b6f0)[0x7f7a343216f0]
/usr/lib/libQtGui.so.4(QApplication::x11ProcessEvent(_XEvent*)+0x864)[0x7f7a342f8904]
/usr/lib/libQtGui.so.4(+0x26e882)[0x7f7a34324882]
/lib/libglib-2.0.so.0(g_main_context_dispatch+0x1f2)[0x7f7a2ca088c2]
/lib/libglib-2.0.so.0(+0x42748)[0x7f7a2ca0c748]
/lib/libglib-2.0.so.0(g_main_context_iteration+0x6c)[0x7f7a2ca0c8fc]
/usr/lib/libQtCore.so.4(QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)+0x73)[0x7f7a34ee4513]
/usr/lib/libQtGui.so.4(+0x26e46e)[0x7f7a3432446e]
/usr/lib/libQtCore.so.4(QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)+0x32)[0x7f7a34eb9992]
/usr/lib/libQtCore.so.4(QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>)+0xdc)[0x7f7a34eb9d6c]
/usr/lib/libQtCore.so.4(QCoreApplication::exec()+0xbb)[0x7f7a34ebdaab]
/usr/local/qgis-1.8/bin/qgis(main+0x2430)[0x53083c]
/lib/libc.so.6(__libc_start_main+0xfd)[0x7f7a324cac4d]
/usr/local/qgis-1.8/bin/qgis[0x52df79]
/usr/local/qgis_devel/bin/qgis: Zeile 2: 30487 Abgebrochen             /usr/local/qgis-1.8/bin/qgis_

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• delete_last_vertex.png (bjpfei -)

[qgib]

Author Name: Giovanni Manghi (@gioman)

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Is this a regression (it used to work in 1.7.4?)?

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• status_id was changed from Open to Feedback
• operating_system was changed from Ubuntu Server to Ubuntu

[qgib]

Author Name: bjpfei - (bjpfei -)

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I think so.
Tested it in our old 1.7.4 version and in Code Version 1fcfde2 and it worked.

[qgib]

Author Name: Giovanni Manghi (@gioman)

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bjpfei - wrote:

Code Version 1fcfde2 and it worked.

do you mean that in qgis master it works correctly?

[qgib]

Author Name: bjpfei - (bjpfei -)

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I don't know if it works correctly in master.
1fcfde2 is not an actual version of master.It is an old version of master - a 1.8rc which we compiled in spring.

[qgib]

Author Name: Giovanni Manghi (@gioman)

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bjpfei - wrote:

I don't know if it works correctly in master.

can you give it a try? under Windows you can use osgeo4w.

If it is a regression we must tag this ticket as blocker. If it is a regression and meanwhile it was fixed in master then we should close this ticket as fixed. Thanks in advance.

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• fixed_version_id was changed from Version 1.8.0 to Version 2.0.0

[qgib]

Author Name: bjpfei - (bjpfei -)

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Sorry we can't test this on actual version of master at the moment.
Does anybody else has the chance to test it?
Thanks in advance

[qgib]

Author Name: cmoe - (cmoe -)

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Just tested on 777ce59 under ubuntu12.04: After deleting the last vertex, the marker is still visible, but Qgis doesn't crash anymore.

regards
cmoe

[qgib]

Author Name: cmoe - (cmoe -)

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Just an update: It will crash, if press delete on the time the already deleted vertex is still marked.

1.) Start editing a polygon layer.
2.) Search the last vertex of the polygon (it will be marked blud) and delete it.
3.) The blue marker still exists, but the polygon shape will be whithout this vertex.
4.) Now press delete to get rid of the needless blue marker
5.) Qgis crashes!

regards Cédric

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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Fixed in changeset "f3acfda57b5aeb0008dd37ffaacd60e94ec20b26".

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• status_id was changed from Feedback to Closed