Use default argument provided by field-specifier function

Author: sharkdp

crates/ty_python_semantic/resources/mdtest/dataclasses/fields.md

@@ -11,7 +11,7 @@ class Member:
     role: str = field(default="user")
     tag: str | None = field(default=None, init=False)
 
-# revealed: (self: Member, name: str, role: str = Literal["user"]) -> None
+# revealed: (self: Member, name: str, role: str = str) -> None
 reveal_type(Member.__init__)
 
 alice = Member(name="Alice", role="admin")
@@ -37,7 +37,7 @@ class Data:
     content: list[int] = field(default_factory=list)
     timestamp: datetime = field(default_factory=datetime.now, init=False)
 
-# revealed: (self: Data, content: list[int] = list[Unknown]) -> None
+# revealed: (self: Data, content: list[int] = list[int]) -> None
 reveal_type(Data.__init__)
 
 data = Data([1, 2, 3])
@@ -63,7 +63,7 @@ class Person:
     age: int | None = field(default=None, kw_only=True)
     role: str = field(default="user", kw_only=True)
 
-# revealed: (self: Person, name: str, *, age: int | None = None, role: str = Literal["user"]) -> None
+# revealed: (self: Person, name: str, *, age: int | None = int | None, role: str = str) -> None
 reveal_type(Person.__init__)
 
 alice = Person(role="admin", name="Alice")
@@ -82,7 +82,7 @@ def get_default() -> str:
 
 reveal_type(field(default=1))  # revealed: dataclasses.Field[Literal[1]]
 reveal_type(field(default=None))  # revealed: dataclasses.Field[None]
-reveal_type(field(default_factory=get_default))  # revealed: dataclasses.Field[str]
+reveal_type(field(default_factory=get_default))  # revealed: dataclasses.Field[Unknown]
 ```
 
 ## dataclass_transform field_specifiers

crates/ty_python_semantic/src/types/call/bind.rs

@@ -609,13 +609,10 @@ impl<'db> Bindings<'db> {
                         let init = overload.parameter_type_by_name("init").unwrap_or(None);
                         let kw_only = overload.parameter_type_by_name("kw_only").unwrap_or(None);
 
-                        let default_ty = match (default, default_factory) {
-                            (Some(default_ty), _) => Some(default_ty),
-                            (_, Some(default_factory_ty)) => default_factory_ty
-                                .try_call(db, &CallArguments::none())
-                                .map(|binding| binding.return_type(db))
-                                .ok(),
-                            _ => None,
+                        let default_ty = if default.is_some() || default_factory.is_some() {
+                            Some(overload.return_ty)
+                        } else {
+                            None
                         };
 
                         let init = init