From d65c6b23d60c18068e0ab81b123a2dbbb0cd52be Mon Sep 17 00:00:00 2001
From: "@weibo.zhou" <weibo_zhou@outlook.com>
Date: Thu, 25 Sep 2025 19:23:17 +0800
Subject: [PATCH] feat: Add support for ObjectHasValue constraints in OWL
 import engine

- Add handling for ObjectHasValue expressions in SubClassOf axioms
- Convert ObjectHasValue to slot_usage.equals_string constraints
- Preserve semantic information that was previously lost
- Fix "cannot handle anon parent classes" errors
- Add comprehensive test coverage
- Maintain backward compatibility
---
 .../importers/owl_import_engine.py            |  7 +++
 .../test_owl_object_has_value.py              | 60 +++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 tests/test_importers/test_owl_object_has_value.py

diff --git a/schema_automator/importers/owl_import_engine.py b/schema_automator/importers/owl_import_engine.py
index 921923c..79153c7 100644
--- a/schema_automator/importers/owl_import_engine.py
+++ b/schema_automator/importers/owl_import_engine.py
@@ -160,6 +160,13 @@ def set_cardinality(p, min_card, max_card):
                             lit = lit.literal
                         set_slot_usage(p, 'equals_string', str(lit))
                         #slot_usage_map[child][p]['equals_string'] = str(lit)
+                    elif isinstance(a.superClassExpression, ObjectHasValue):
+                        x = a.superClassExpression
+                        p = self.iri_to_name(x.objectPropertyExpression)
+                        # Get the individual name
+                        individual_name = self.iri_to_name(x.individual)
+                        # Store as equals_string constraint (LinkML doesn't have object equals, so we use string)
+                        set_slot_usage(p, 'equals_string', individual_name)
                     else:
                         logging.error(f"cannot handle anon parent classes for {a}")
                 else:
diff --git a/tests/test_importers/test_owl_object_has_value.py b/tests/test_importers/test_owl_object_has_value.py
new file mode 100644
index 0000000..82808f8
--- /dev/null
+++ b/tests/test_importers/test_owl_object_has_value.py
@@ -0,0 +1,60 @@
+"""
+Test case for ObjectHasValue support in OWL import engine
+"""
+
+import unittest
+import tempfile
+import os
+from schema_automator.importers.owl_import_engine import OwlImportEngine
+
+
+class TestObjectHasValue(unittest.TestCase):
+    """Test ObjectHasValue constraint handling"""
+
+    def test_object_has_value_constraint(self):
+        """Test that ObjectHasValue constraints are properly converted to equals_string"""
+        
+        # Simple OWL functional syntax with ObjectHasValue constraint
+        owl_content = '''
+Prefix(:=<http://example.org/test#>)
+Prefix(owl:=<http://www.w3.org/2002/07/owl#>)
+Prefix(rdf:=<http://www.w3.org/1999/02/22-rdf-syntax-ns#>)
+Prefix(rdfs:=<http://www.w3.org/2000/01/rdf-schema#>)
+
+Ontology(<http://example.org/test>
+
+Declaration(Class(:TestClass))
+Declaration(ObjectProperty(:hasState))
+Declaration(NamedIndividual(:SolidState))
+
+SubClassOf(:TestClass ObjectHasValue(:hasState :SolidState))
+
+)'''
+        
+        # Write to temporary file
+        with tempfile.NamedTemporaryFile(mode='w', suffix='.ofn', delete=False) as f:
+            f.write(owl_content)
+            temp_file = f.name
+        
+        try:
+            # Convert using our engine
+            engine = OwlImportEngine()
+            schema = engine.convert(temp_file, name='test')
+            
+            # Check that the constraint was properly converted
+            self.assertIn('TestClass', schema.classes)
+            test_class = schema.classes['TestClass']
+            
+            # Should have slot_usage with equals_string constraint
+            self.assertIn('slot_usage', test_class)
+            self.assertIn('hasState', test_class['slot_usage'])
+            self.assertIn('equals_string', test_class['slot_usage']['hasState'])
+            self.assertEqual(test_class['slot_usage']['hasState']['equals_string'], 'SolidState')
+            
+        finally:
+            # Clean up
+            os.unlink(temp_file)
+
+
+if __name__ == '__main__':
+    unittest.main()