Fix transitive local reference resolution in external schema files (#2577)

* Add Feedback API schema and models for feedback items

* Fix transitive local reference resolution in test input type

Author: koxudaxi

src/datamodel_code_generator/parser/jsonschema.py

@@ -1914,7 +1914,7 @@ def _parse_file(
                 reserved_refs = set(self.reserved_refs.get(key) or [])
                 while reserved_refs:
                     for reserved_path in sorted(reserved_refs):
-                        reference = self.model_resolver.get(reserved_path)
+                        reference = self.model_resolver.references.get(reserved_path)
                         if not reference or reference.loaded:
                             continue
                         object_paths = reserved_path.split("#/", 1)[-1].split("/")

tests/data/expected/main/openapi/external_ref_with_transitive_local_ref/output.py

@@ -0,0 +1,20 @@
+# generated by datamodel-codegen:
+#   filename:  openapi.yaml
+#   timestamp: 2019-07-26T00:00:00+00:00
+
+from __future__ import annotations
+
+from pydantic import AwareDatetime, BaseModel
+
+
+class FeedbackItemBase(BaseModel):
+    id: int
+    message: str
+
+
+class FeedbackItemCreate(FeedbackItemBase):
+    user_id: int
+
+
+class FeedbackItem(FeedbackItemBase):
+    created_at: AwareDatetime

tests/data/openapi/external_ref_with_transitive_local_ref/openapi.yaml

@@ -0,0 +1,38 @@
+openapi: 3.1.0
+info:
+  title: Feedback API
+  version: 1.0.0
+paths:
+  /feedback:
+    get:
+      summary: Get all feedback items
+      responses:
+        '200':
+          description: List of feedback items
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: './schemas/feedback.yaml#/FeedbackItem'
+    post:
+      summary: Create a feedback item
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: './schemas/feedback.yaml#/FeedbackItemCreate'
+      responses:
+        '201':
+          description: Created feedback item
+          content:
+            application/json:
+              schema:
+                $ref: './schemas/feedback.yaml#/FeedbackItem'
+components:
+  schemas:
+    FeedbackItem:
+      $ref: './schemas/feedback.yaml#/FeedbackItem'
+    FeedbackItemCreate:
+      $ref: './schemas/feedback.yaml#/FeedbackItemCreate'

tests/data/openapi/external_ref_with_transitive_local_ref/schemas/feedback.yaml

@@ -0,0 +1,31 @@
+FeedbackItemBase:
+  type: object
+  properties:
+    id:
+      type: integer
+    message:
+      type: string
+  required:
+    - id
+    - message
+
+FeedbackItem:
+  allOf:
+    - $ref: '#/FeedbackItemBase'
+    - type: object
+      properties:
+        created_at:
+          type: string
+          format: date-time
+      required:
+        - created_at
+
+FeedbackItemCreate:
+  allOf:
+    - $ref: '#/FeedbackItemBase'
+    - type: object
+      properties:
+        user_id:
+          type: integer
+      required:
+        - user_id

tests/main/openapi/test_main_openapi.py

@@ -2377,3 +2377,15 @@ def test_main_openapi_webhooks_with_parameters(output_file: Path) -> None:
         assert_func=assert_file_content,
         extra_args=["--openapi-scopes", "schemas", "webhooks", "parameters"],
     )
+
+
+def test_main_openapi_external_ref_with_transitive_local_ref(output_file: Path) -> None:
+    """Test OpenAPI generation with external ref that has transitive local refs."""
+    run_main_and_assert(
+        input_path=OPEN_API_DATA_PATH / "external_ref_with_transitive_local_ref" / "openapi.yaml",
+        output_path=output_file,
+        input_file_type="openapi",
+        assert_func=assert_file_content,
+        expected_file="external_ref_with_transitive_local_ref/output.py",
+        extra_args=["--output-model-type", "pydantic_v2.BaseModel"],
+    )

tests/test_infer_input_type.py

@@ -53,6 +53,8 @@ def assert_invalid_infer_input_type(file: Path) -> None:
             continue
         if "reference_same_hierarchy_directory" in file.parts:
             continue
+        if "external_ref_with_transitive_local_ref" in file.parts and file.name != "openapi.yaml":
+            continue
         if file.name.endswith((
             "aliases.json",
             "extra_data.json",