Fix usage with default and default_factory arguments

RELEASE.md

@@ -0,0 +1,3 @@
+Release type: minor
+
+Fix using strawberry with default or default_factory (dataclasses basics)

strawberry/field.py

@@ -221,7 +221,15 @@
  if self.base_resolver:
  return self.base_resolver(*args, **kwargs)
 
- return self.default_resolver(source, self.python_name)
+ try:
+ return self.default_resolver(source, self.python_name)
+ except AttributeError as exc:
+ # fallback if source is not available or is not an proper instance
+ if self.default:
+ return self.default
+ if self.default_factory:
+ return self.default_factory()
+ raise exc
 
  @property
  def is_basic_field(self) -> bool:

tests/schema/test_basic.py

@@ -580,3 +580,43 @@ class FooBar2:
  FooBar(foo=1)
  FooBar(bar=2)
  FooBar(foo=1, bar=2)
+
+
+def test_use_default_factory_on_root():
+ @strawberry.type
+ class Sub:
+ foo: str = strawberry.field(default="bar")
+
+ @strawberry.type
+ class Query:
+ sub: Sub = strawberry.field(default_factory=Sub)
+
+ schema = strawberry.Schema(query=Query)
+
+ result = schema.execute_sync(
+ """
+ query TestQuery{
+ sub {
+ foo
+ }
+ }
+ """
+ )
+ assert result.data == {"sub": {"foo": "bar"}}
+
+
+def test_use_default_on_root():
+ @strawberry.type
+ class Query:
+ sub: bool = strawberry.field(default=True)
+
+ schema = strawberry.Schema(query=Query)
+
+ result = schema.execute_sync(
+ """
+ query TestQuery{
+ sub
+ }
+ """
+ )
+ assert result.data == {"sub": True}