Deal with missing entity.type

CMakeLists.txt

@@ -27,7 +27,7 @@ cmake_minimum_required(VERSION 3.23)
 # set the project name
 project(
 	libcifpp
-	VERSION 7.0.9
+	VERSION 7.0.10
 	LANGUAGES CXX)
 
 list(PREPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")

changelog

@@ -1,3 +1,6 @@
+Version 7.0.10
+- Deal with missing _entity.type in reconstructing mmCIF files
+
 Version 7.0.9
 - Using cif::file::load_dictionary it is now possible to
   load a dictionary along with its extensions in one go.

src/pdb/reconstruct.cpp

@@ -100,10 +100,35 @@ void checkEntities(datablock &db)
 
 	for (auto entity : db["entity"].find("formula_weight"_key == null or "formula_weight"_key == 0))
 	{
-		const auto &[entity_id, type] = entity.get<std::string, std::string>("id", "type");
+		auto &&[entity_id, type] = entity.get<std::string, std::string>("id", "type");
 
 		float formula_weight = 0;
 
+		if (type.empty())	// yes, that happens
+		{
+			const auto comp_id = db["atom_site"].find_first<std::string>("label_entity_id"_key == entity_id, "label_comp_id");
+			auto compound = cf.create(comp_id);
+			if (compound != nullptr)
+			{
+				if (compound->is_base() or compound->is_peptide())
+					type = "polymer";
+				else if (compound->is_water())
+					type = "water";
+				else
+				{
+					if (db["pdbx_entity_branch_link"].exists("entity_id"_key == entity_id))
+						type = "branched";
+					else
+						type = "non-polymer";
+				}
+			}
+
+			if (type.empty())
+				throw std::runtime_error("Entity without type and cannot determine what it should be");
+
+			entity["type"] = type;
+		}
+
 		if (type == "polymer")
 		{
 			int n = 0;