Fix deep hierarchy type inheritance in allOf property overrides (#2843)

Author: koxudaxi

src/datamodel_code_generator/parser/jsonschema.py

@@ -1775,11 +1775,24 @@ def _merge_properties_with_parent_constraints(
         }
         return model_validate(self.SCHEMA_OBJECT_TYPE, merged_obj_dict)
 
-    def _get_inherited_field_type(self, prop_name: str, base_classes: list[Reference]) -> DataType | None:
-        """Get the data type for an inherited property from parent schemas."""
+    def _get_inherited_field_type(  # noqa: PLR0912
+        self, prop_name: str, base_classes: list[Reference], visited: frozenset[str] | None = None
+    ) -> DataType | None:
+        """Get the data type for an inherited property from parent schemas.
+
+        Recursively traverses the inheritance chain when a parent property
+        doesn't have type information but the parent itself inherits from another schema.
+        """
+        if visited is None:
+            visited = frozenset()
+
         for base in base_classes:
             if not base.path:  # pragma: no cover
                 continue
+            if base.path in visited:  # pragma: no cover
+                continue
+            visited |= {base.path}
+
             if "#" in base.path:
                 file_part, fragment = base.path.split("#", 1)
                 ref = f"{file_part}#{fragment}" if file_part else f"#{fragment}"
@@ -1789,14 +1802,21 @@ def _get_inherited_field_type(self, prop_name: str, base_classes: list[Reference
                 parent_schema = self._load_ref_schema_object(ref)
             except Exception:  # pragma: no cover  # noqa: BLE001, S112
                 continue
-            if not parent_schema.properties:  # pragma: no cover
-                continue
-            prop_schema = parent_schema.properties.get(prop_name)
-            if not isinstance(prop_schema, JsonSchemaObject):  # pragma: no cover
-                continue
-            result = self._build_lightweight_type(prop_schema)
-            if result is not None:
-                return result
+
+            if parent_schema.properties:
+                prop_schema = parent_schema.properties.get(prop_name)
+                if isinstance(prop_schema, JsonSchemaObject):
+                    result = self._build_lightweight_type(prop_schema)
+                    if result is not None:
+                        return result
+
+            if parent_schema.allOf:
+                grandparent_refs = [self.model_resolver.add_ref(item.ref) for item in parent_schema.allOf if item.ref]
+                if grandparent_refs:
+                    result = self._get_inherited_field_type(prop_name, grandparent_refs, visited)
+                    if result is not None:
+                        return result
+
         return None
 
     def _schema_signature(self, prop_schema: JsonSchemaObject | bool) -> str | bool:  # noqa: FBT001, PLR6301

tests/data/expected/main/jsonschema/all_of_deep_hierarchy_property_override.py

@@ -0,0 +1,20 @@
+# generated by datamodel-codegen:
+#   filename:  all_of_deep_hierarchy_property_override.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from pydantic import BaseModel, constr
+
+
+class Entity(BaseModel):
+    type: str
+
+
+class Thing(Entity):
+    type: str
+    name: constr(min_length=1)
+
+
+class Person(Thing):
+    type: str | None = 'playground:Person'

tests/data/expected/main/jsonschema/all_of_hierarchy_inline_allof.py

@@ -0,0 +1,18 @@
+# generated by datamodel-codegen:
+#   filename:  all_of_hierarchy_inline_allof.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from typing import Any
+
+from pydantic import BaseModel
+
+
+class Parent(BaseModel):
+    name: str | None = None
+    status: Any | None = 'parent-status'
+
+
+class Child(Parent):
+    status: Any | None = 'child-status'

tests/data/expected/main/jsonschema/all_of_hierarchy_property_not_in_ancestor.py

@@ -0,0 +1,21 @@
+# generated by datamodel-codegen:
+#   filename:  all_of_hierarchy_property_not_in_ancestor.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from typing import Any
+
+from pydantic import BaseModel
+
+
+class Grandparent(BaseModel):
+    name: str | None = None
+
+
+class Parent(Grandparent):
+    category: Any | None = 'parent-category'
+
+
+class Child(Parent):
+    category: Any | None = 'child-category'

tests/data/expected/main/jsonschema/all_of_very_deep_hierarchy_property_override.py

@@ -0,0 +1,30 @@
+# generated by datamodel-codegen:
+#   filename:  all_of_very_deep_hierarchy_property_override.json
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from pydantic import BaseModel
+
+
+class Base(BaseModel):
+    id: str
+
+
+class Entity(Base):
+    type: str
+
+
+class Thing(Entity):
+    type: str | None = 'Thing'
+    name: str
+
+
+class Person(Thing):
+    type: str | None = 'Person'
+    age: int | None = None
+
+
+class SpecificPerson(Person):
+    type: str | None = 'SpecificPerson'
+    id: str | None = 'specific-id'

tests/data/jsonschema/all_of_deep_hierarchy_property_override.json

@@ -0,0 +1,32 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "https://example.com/person.schema.json",
+  "title": "Person",
+  "$defs": {
+    "Entity": {
+      "type": "object",
+      "properties": {
+        "type": { "type": "string", "default": "playground:Entity" }
+      },
+      "required": ["type"]
+    },
+    "Thing": {
+      "allOf": [
+        { "$ref": "#/$defs/Entity" }
+      ],
+      "type": "object",
+      "properties": {
+        "type": { "default": "playground:Thing" },
+        "name": { "type": "string", "minLength": 1 }
+      },
+      "required": ["type", "name"]
+    }
+  },
+  "type": "object",
+  "allOf": [
+    { "$ref": "#/$defs/Thing" }
+  ],
+  "properties": {
+    "type": { "default": "playground:Person" }
+  }
+}

tests/data/jsonschema/all_of_hierarchy_inline_allof.json

@@ -0,0 +1,27 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "title": "Child",
+  "$defs": {
+    "Parent": {
+      "allOf": [
+        {
+          "type": "object",
+          "properties": {
+            "name": { "type": "string" }
+          }
+        }
+      ],
+      "type": "object",
+      "properties": {
+        "status": { "default": "parent-status" }
+      }
+    }
+  },
+  "type": "object",
+  "allOf": [
+    { "$ref": "#/$defs/Parent" }
+  ],
+  "properties": {
+    "status": { "default": "child-status" }
+  }
+}

tests/data/jsonschema/all_of_hierarchy_property_not_in_ancestor.json

@@ -0,0 +1,28 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "title": "Child",
+  "$defs": {
+    "Grandparent": {
+      "type": "object",
+      "properties": {
+        "name": { "type": "string" }
+      }
+    },
+    "Parent": {
+      "allOf": [
+        { "$ref": "#/$defs/Grandparent" }
+      ],
+      "type": "object",
+      "properties": {
+        "category": { "default": "parent-category" }
+      }
+    }
+  },
+  "type": "object",
+  "allOf": [
+    { "$ref": "#/$defs/Parent" }
+  ],
+  "properties": {
+    "category": { "default": "child-category" }
+  }
+}

tests/data/jsonschema/all_of_very_deep_hierarchy_property_override.json

@@ -0,0 +1,52 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "title": "SpecificPerson",
+  "$defs": {
+    "Base": {
+      "type": "object",
+      "properties": {
+        "id": { "type": "string" }
+      },
+      "required": ["id"]
+    },
+    "Entity": {
+      "allOf": [
+        { "$ref": "#/$defs/Base" }
+      ],
+      "type": "object",
+      "properties": {
+        "type": { "type": "string", "default": "Entity" }
+      },
+      "required": ["type"]
+    },
+    "Thing": {
+      "allOf": [
+        { "$ref": "#/$defs/Entity" }
+      ],
+      "type": "object",
+      "properties": {
+        "type": { "default": "Thing" },
+        "name": { "type": "string" }
+      },
+      "required": ["name"]
+    },
+    "Person": {
+      "allOf": [
+        { "$ref": "#/$defs/Thing" }
+      ],
+      "type": "object",
+      "properties": {
+        "type": { "default": "Person" },
+        "age": { "type": "integer" }
+      }
+    }
+  },
+  "type": "object",
+  "allOf": [
+    { "$ref": "#/$defs/Person" }
+  ],
+  "properties": {
+    "type": { "default": "SpecificPerson" },
+    "id": { "default": "specific-id" }
+  }
+}

tests/main/jsonschema/test_main_jsonschema.py

@@ -1423,6 +1423,54 @@ def test_main_all_of_multi_ref_with_property_override(output_file: Path) -> None
         )
 
 
+def test_main_all_of_deep_hierarchy_property_override(output_file: Path) -> None:
+    """Test allOf with deep hierarchy inherits types from grandparent when parent has partial override."""
+    with chdir(JSON_SCHEMA_DATA_PATH):
+        run_main_and_assert(
+            input_path=Path("all_of_deep_hierarchy_property_override.json"),
+            output_path=output_file,
+            input_file_type="jsonschema",
+            assert_func=assert_file_content,
+            expected_file="all_of_deep_hierarchy_property_override.py",
+        )
+
+
+def test_main_all_of_very_deep_hierarchy_property_override(output_file: Path) -> None:
+    """Test allOf with 4+ levels of hierarchy inherits types from great-grandparent."""
+    with chdir(JSON_SCHEMA_DATA_PATH):
+        run_main_and_assert(
+            input_path=Path("all_of_very_deep_hierarchy_property_override.json"),
+            output_path=output_file,
+            input_file_type="jsonschema",
+            assert_func=assert_file_content,
+            expected_file="all_of_very_deep_hierarchy_property_override.py",
+        )
+
+
+def test_main_all_of_hierarchy_property_not_in_ancestor(output_file: Path) -> None:
+    """Test allOf hierarchy when property override is not found in any ancestor."""
+    with chdir(JSON_SCHEMA_DATA_PATH):
+        run_main_and_assert(
+            input_path=Path("all_of_hierarchy_property_not_in_ancestor.json"),
+            output_path=output_file,
+            input_file_type="jsonschema",
+            assert_func=assert_file_content,
+            expected_file="all_of_hierarchy_property_not_in_ancestor.py",
+        )
+
+
+def test_main_all_of_hierarchy_inline_allof(output_file: Path) -> None:
+    """Test allOf hierarchy when parent has inline allOf without $ref."""
+    with chdir(JSON_SCHEMA_DATA_PATH):
+        run_main_and_assert(
+            input_path=Path("all_of_hierarchy_inline_allof.json"),
+            output_path=output_file,
+            input_file_type="jsonschema",
+            assert_func=assert_file_content,
+            expected_file="all_of_hierarchy_inline_allof.py",
+        )
+
+
 @pytest.mark.skipif(
     black.__version__.split(".")[0] >= "24",
     reason="Installed black doesn't support the old style",