Dissolving a line feature using the 'Unsplit lines' option causes ArcGIS Pro to crash if the data contains null geometry.

Workaround

1. Add the line feature class into the map.
2. In the Geoprocessing window, search for the Repair Geometry tool to check on the geometry of the feature class.
3. Select the line feature as the input feature.
4. Check the checkbox for 'Delete Features with Null Geometry'.
5. Set the Validation Method as 'Esri' and run the tool.
6. Run the Dissolve tool using the repaired line feature (check the checkbox for the 'Unsplit lines' option).

Schritte zur Reproduzierung