Fix invalid layer in value relation field

[tomasMizera]

It seems there is some edge-case scenario where a referenced layer in the value relation field is not available (probably a missing layer or some other project misconfiguration ... I could not reproduce it with my projects)

Logs are indicating that mTitleField is empty, thus we continue to FeaturesModel::FeatureTitle with pair->layer() as nullptr. See

mobile/app/valuerelationfeaturesmodel.cpp

Lines 87 to 96 in dd05acc

	QVariant ValueRelationFeaturesModel::featureTitle( const FeatureLayerPair &pair ) const
	{
	if ( !mTitleField.isEmpty() )
	{
	return pair.feature().attribute( mTitleField );
	}
	return FeaturesModel::featureTitle( pair );
	}

See bug report logs for more details -> Fixes #3535

[VitorVieiraZ]

Looking good to me. There is just an issue in the code layout check.

[uclaros]

When title is empty we return pair.feature().id()
Should we not be returning the same for this case too?

[tomasMizera]

Not sure, if the layer is invalid, I'd expect everything is broken 💥

[github-actions]

Pull Request Test Coverage Report for Build 10072387691

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 34 unchanged lines in 4 files lost coverage.
• Overall coverage decreased (-0.02%) to 59.998%

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Files with Coverage Reduction	New Missed Lines	%
input/app/featuresmodel.h	1	0.0%
input/app/projectsmodel.cpp	1	69.17%
input/app/attributes/attributecontroller.cpp	1	77.43%
input/app/featuresmodel.cpp	31	67.79%

Totals
Change from base Build 9953082018:	-0.02%
Covered Lines:	7699
Relevant Lines:	12832

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💛 - Coveralls