Add default to JSON schema when const is True

changes/4031-aminalaee.md

@@ -0,0 +1 @@
+Add `default` value in JSON Schema when `const=True`

pydantic/schema.py

@@ -210,12 +210,7 @@ def get_field_info_schema(field: ModelField, schema_overrides: bool = False) ->
         schema_['description'] = field.field_info.description
         schema_overrides = True
 
-    if (
-        not field.required
-        and not field.field_info.const
-        and field.default is not None
-        and not is_callable_type(field.outer_type_)
-    ):
+    if not field.required and field.default is not None and not is_callable_type(field.outer_type_):
         schema_['default'] = encode_default(field.default)
         schema_overrides = True
 

tests/test_main.py

@@ -585,12 +585,14 @@ class Model(BaseModel):
         'properties': {
             'a': {
                 'const': [SubModel(b=1), SubModel(b=2), SubModel(b=3)],
+                'default': [{'b': 1}, {'b': 2}, {'b': 3}],
                 'items': {'$ref': '#/definitions/SubModel'},
                 'title': 'A',
                 'type': 'array',
             },
             'b': {
                 'const': [{'b': 4}, {'b': 5}, {'b': 6}],
+                'default': [{'b': 4}, {'b': 5}, {'b': 6}],
                 'items': {'$ref': '#/definitions/SubModel'},
                 'title': 'B',
                 'type': 'array',

tests/test_schema.py

@@ -549,7 +549,7 @@ class Model(BaseModel):
     assert Model.schema() == {
         'title': 'Model',
         'type': 'object',
-        'properties': {'a': {'title': 'A', 'type': 'string', 'const': 'some string'}},
+        'properties': {'a': {'title': 'A', 'type': 'string', 'const': 'some string', 'default': 'some string'}},
     }