Fix #7073

python/plugins/fTools/tools/doIntersectLines.py

@@ -148,6 +148,7 @@ def compute(self, line1, line2, field1, field2, outPath, progressBar):
 
         index = ftools_utils.createIndex( provider2 )
 
+        singlelayer_tempList = []
         fit1 = provider1.getFeatures( QgsFeatureRequest().setSubsetOfAttributes([index1]) )
         while fit1.nextFeature(inFeat):
             inGeom = inFeat.geometry()
@@ -169,10 +170,19 @@ def compute(self, line1, line2, field1, field2, outPath, progressBar):
                             tempList.append(tempGeom.asPoint())
 
                         for j in tempList:
-                            outFeat.setGeometry(tempGeom.fromPoint(j))
-                            outFeat.setAttribute(0, v1)
-                            outFeat.setAttribute(1, v2)
-                            writer.addFeature(outFeat)
+                            # if same layer, avoid insert duplicated points
+                            if line1 == line2:
+                                if not j in singlelayer_tempList:
+                                    singlelayer_tempList.append(j)
+                                    outFeat.setGeometry(tempGeom.fromPoint(j))
+                                    outFeat.setAttribute(0, v1)
+                                    outFeat.setAttribute(1, v2)
+                                    writer.addFeature(outFeat)
+                            else:
+                                outFeat.setGeometry(tempGeom.fromPoint(j))
+                                outFeat.setAttribute(0, v1)
+                                outFeat.setAttribute(1, v2)
+                                writer.addFeature(outFeat)
 
             start = start + add
             progressBar.setValue(start)