Make it work to use $ref as an alias (#6568)

pydantic · Jul 12, 2023 · ed0171c · ed0171c
1 parent 1e50b0d
commit ed0171c
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Showing 2 changed files with 18 additions and 3 deletions.
diff --git a/pydantic/json_schema.py b/pydantic/json_schema.py
@@ -191,8 +191,8 @@ def remap_json_schema(self, schema: Any) -> Any:
             return [self.remap_json_schema(item) for item in schema]
         elif isinstance(schema, dict):
             for key, value in schema.items():
-                if key == '$ref':
-                    schema['$ref'] = self.remap_json_ref(JsonRef(schema['$ref']))
+                if key == '$ref' and isinstance(value, str):
+                    schema['$ref'] = self.remap_json_ref(JsonRef(value))
                 elif key == '$defs':
                     schema['$defs'] = {
                         self.remap_defs_ref(DefsRef(key)): self.remap_json_schema(value)
@@ -1959,6 +1959,8 @@ def _add_json_refs(schema: Any) -> None:
             if isinstance(schema, dict):
                 if '$ref' in schema:
                     json_ref = JsonRef(schema['$ref'])
+                    if not isinstance(json_ref, str):
+                        return  # in this case, '$ref' might have been the name of a property
                     already_visited = json_ref in json_refs
                     json_refs[json_ref] += 1
                     if already_visited:
@@ -2213,7 +2215,8 @@ def _get_all_json_refs(item: Any) -> set[JsonRef]:
     refs: set[JsonRef] = set()
     if isinstance(item, dict):
         for key, value in item.items():
-            if key == '$ref':
+            if key == '$ref' and isinstance(value, str):
+                # the isinstance check ensures that '$ref' isn't the name of a property, etc.
                 refs.add(JsonRef(value))
             elif isinstance(value, dict):
                 refs.update(_get_all_json_refs(value))

diff --git a/tests/test_json_schema.py b/tests/test_json_schema.py
@@ -5060,3 +5060,15 @@ class Bar(BaseModel):
         'title': 'Foo',
         'type': 'object',
     }
+
+
+def test_dollar_ref_alias():
+    class MyModel(BaseModel):
+        my_field: str = Field(alias='$ref')
+
+    assert MyModel.model_json_schema() == {
+        'properties': {'$ref': {'title': '$Ref', 'type': 'string'}},
+        'required': ['$ref'],
+        'title': 'MyModel',
+        'type': 'object',
+    }