Crash QGIS 2.10.1 after select MultiGeometry features from PostGIS into Temporary Layer

[qgib]

Author Name: Evgeniy Z (Evgeniy Z)
Original Redmine Issue: 13308
Affected QGIS version: 2.10.1

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I have created a plugin which selects objects from a PostGIS table by rectangle and puts it into new Memory Layer. Type of geometry in PostGis table - MultiLineString. Adding features to the Memory Layer (its type also MultiLineString) is done successfully. But if you try zoom to Layer and perform any manipulations with map, QGIS is going to crash.
This situation occurs in QGIS 2.10. In 2.8.2 it worked well. Therefore I tried to convert MultiLineString to LineString - QGIS does not crashs, but it is unacceptable for work with some data...

Below is the example code for QGIS python console to reproduce situation and shapefile with some geometry data for tests.

Steps for reproduce:

1. Load shapefile into PostGIS base;
2. Paste code to console, editing parameters for connections. (It will create new memory layer "Result_Layer" and put to it data from PostGIS table "test_shape");
3. Press "Zoom to Layer" to see geometry. (Now we see, that all features have been added);
4. try Zoom In, Zoom Out, Pan map or some any manipulation with map extent in "Result_Layer" area.
5. QGIS CRASH.

from PyQt4.QtCore import *
from PyQt4.QtGui import *
from qgis.core import *
from PyQt4.QtSql import *

self = qgis.utils
uri = QgsDataSourceURI()
uri.setConnection("10.1.1.6", "5432", "Database", "Username", "Password")
 # "test shape" - Our layer name in base after import from shapefile.
 # "public" - schema
uri.setDataSource("public", "test_shape", "geom", "", "gid")
vlayer=QgsVectorLayer(uri.uri(), "tot", "postgres")
        
resultl = QgsVectorLayer("MultiLineString", "Result_select", "memory")
QgsMapLayerRegistry.instance().addMapLayer(resultl, True)
resultpr = resultl.dataProvider()
for feature in vlayer.getFeatures():
            resultpr.addFeatures([feature])

self.iface.mapCanvas().refresh()
print 'done'

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• Test_shapefile.zip (Evgeniy Z)
• Crash.avi (Evgeniy Z)

[qgib]

Author Name: Salvatore Larosa (@slarosa)

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I am not able to reproduce the crash in master version.

Which platform are you using?
Have you tried to reproduce the crash with all plugins deactivated (option --noplugins)?

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• status_id was changed from Open to Feedback

[qgib]

Author Name: Evgeniy Z (Evgeniy Z)

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I am using Windows 7 x64, Windows 10 x32.
Now I tried to reproduce the crash with all plugins deactivated - also crash.

[qgib]

Author Name: Evgeniy Z (Evgeniy Z)

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Demonstration

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• 9040 was configured as Crash.avi

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• Crash.avi (Evgeniy Z)

[qgib]

Author Name: Salvatore Larosa (@slarosa)

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I can confirm it on Windows and I also can confirm it works fine in LTR version.

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• status_id was changed from Feedback to Open

[qgib]

Author Name: Mauricio van den Berg (Mauricio van den Berg)

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I suspect I ran into something caused by the same problem.

Reproducible in the following way:

1. Add multilinestring:

@MLayer = QgsVectorLayer("MultiLineString?crs=epsg:28992", "test", "memory")
MLayer.startEditing()
fet = QgsFeature() 
geomstring = "MULTILINESTRING((166837.841 577100.866,166836.905 577101.214),(166835.031 577101.913,166834.094 577102.262))"
fet.setGeometry(QgsGeometry.fromWkt(geomstring))
MLayer.dataProvider().addFeatures( [fet] ) 
MLayer.commitChanges()
MLayer.updateExtents()
QgsMapLayerRegistry.instance().addMapLayer(MLayer)

2. Zoom out very far
3. Click "zoom to layer" on newly added layer
4. Crash

Also crashes in less easily reproducible ways.

I'm also on QGIS 2.10.1, Windows 7 x64

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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• assigned_to_id was configured as Jürgen Fischer

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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Original problem only reproducable with 2.10.1 (windows 64bit; second example doesn't crash there here either). 2.8.3 and master seem to work fine. Does enabling/disabling geometry simplification on the layer make a difference?

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• status_id was changed from Open to Feedback
• assigned_to_id removed Jürgen Fischer

[qgib]

Author Name: Evgeniy Z (Evgeniy Z)

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Jürgen Fischer, No, enabling/disabling geometry simplification on the layer does not make a difference.

[qgib]

Author Name: Jürgen Fischer (@jef-n)

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Evgeniy Z wrote:

No, enabling/disabling geometry simplification on the layer does not make a difference.

Can you reproduce it in master?

[qgib]

Author Name: Evgeniy Z (Evgeniy Z)

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So in 2.11 master it seems works normal. But I could not track one unexpected crash. I was limited in time.

[qgib]

Author Name: Nyall Dawson (@nyalldawson)

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Not reproducible in master. Please reopen if you experience this with 2.12

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• resolution was changed from to fixed/implemented
• status_id was changed from Feedback to Closed