[processing] Show error when dissolve fails

elpaso · elpaso · commit 1c390748c9f5 · 2018-11-22T17:58:51.000+01:00
Partial fix for #20591 - Dissolve tool failing to produce outputs There is still the GEOS issue to be cheked
diff --git a/src/analysis/processing/qgsalgorithmdissolve.cpp b/src/analysis/processing/qgsalgorithmdissolve.cpp
@@ -212,9 +212,14 @@ QgsDissolveAlgorithm *QgsDissolveAlgorithm::createInstance() const
 
 QVariantMap QgsDissolveAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
 {
-  return processCollection( parameters, context, feedback, []( const QVector< QgsGeometry > &parts )->QgsGeometry
+  return processCollection( parameters, context, feedback, [ & ]( const QVector< QgsGeometry > &parts )->QgsGeometry
   {
-    return QgsGeometry::unaryUnion( parts );
+    QgsGeometry result( QgsGeometry::unaryUnion( parts ) );
+    if ( ! result.lastError().isEmpty() )
+    {
+      feedback->reportError( result.lastError(), true );
+    }
+    return result;
   }, 10000 );
 }
 

Original file line number	Diff line number	Diff line change
`@@ -212,9 +212,14 @@ QgsDissolveAlgorithm *QgsDissolveAlgorithm::createInstance() const`
`212`	`212`
`213`	`213`	`QVariantMap QgsDissolveAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )`
`214`	`214`	`{`
`215`		`- return processCollection( parameters, context, feedback, []( const QVector< QgsGeometry > &parts )->QgsGeometry`
	`215`	`+ return processCollection( parameters, context, feedback, [ & ]( const QVector< QgsGeometry > &parts )->QgsGeometry`
`216`	`216`	`{`
`217`		`- return QgsGeometry::unaryUnion( parts );`
	`217`	`+ QgsGeometry result( QgsGeometry::unaryUnion( parts ) );`
	`218`	`+ if ( ! result.lastError().isEmpty() )`
	`219`	`+ {`
	`220`	`+ feedback->reportError( result.lastError(), true );`
	`221`	`+ }`
	`222`	`+ return result;`
`218`	`223`	`}, 10000 );`
`219`	`224`	`}`
`220`	`225`