Record edit conflict when UPDATE is rebased on top of DELETE

Author: wonder-sk

geodiff/src/geodiffrebase.cpp

@@ -471,7 +471,20 @@ bool _handle_update( const ChangesetEntry &entry, const RebaseMapping &mapping,
   {
     int newPk = mapping.getNewPkey( entry.table->name, pk );
     if ( newPk == RebaseMapping::INVALID_FID )
+    {
+      // our UPDATE conflicts with their DELETE: record as conflict, delete wins
+      ConflictFeature conflictFeature( pk, entry.table->name );
+      for ( size_t i = 0; i < numColumns; i++ )
+      {
+        if ( entry.newValues[i].type() != Value::TypeUndefined )
+        {
+          _addConflictItem( conflictFeature, ( int ) i, entry.oldValues[i], Value(), entry.newValues[i] );
+        }
+      }
+      if ( conflictFeature.isValid() )
+        conflicts.push_back( conflictFeature );
       return false;
+    }
   }
 
   // find the previously new values (will be used as the old values in the rebased version)

geodiff/tests/test_concurrent_commits.cpp

@@ -381,7 +381,7 @@ TEST( ConcurrentCommitsSqlite3Test, test_delete_update )
 {
   std::cout << "geopackage concurent DELETE (base) -> (A) and UPDATE (base) -> (B)" << std::endl;
   std::cout << "(A) deleted the feature 2 and (B) edits the geom of feature 2" << std::endl;
-  std::cout << "expected result: feature 2 is deleted" << std::endl;
+  std::cout << "expected result: feature 2 is deleted, conflict recorded for the discarded update" << std::endl;
 
   bool ret = _test(
                "base.gpkg",
@@ -392,7 +392,7 @@ TEST( ConcurrentCommitsSqlite3Test, test_delete_update )
                1,
                0,
                1,
-               0
+               1
              );
   ASSERT_TRUE( ret );
 }