[ty] synthesize __replace__ for >=3.13

Author: thejchap

crates/ty_python_semantic/resources/mdtest/replace.md

@@ -0,0 +1,58 @@
+# Replace
+
+The replace function and protocol added in Python 3.13:
+<https://docs.python.org/3/whatsnew/3.13.html#copy>
+
+## `replace()` function
+
+It is present in the `copy` module.
+
+```toml
+[environment]
+python-version = "3.13"
+```
+
+```py
+from copy import replace
+```
+
+## `__replace__` protocol
+
+```toml
+[environment]
+python-version = "3.13"
+```
+
+### Dataclasses
+
+```py
+from dataclasses import dataclass
+from copy import replace
+
+@dataclass
+class Point:
+    x: int
+    y: int
+
+a = Point(1, 2)
+
+# TODO: Implement __replace__ method - this should not throw an error
+# error: [unknown-argument]
+b = a.__replace__(x=3)
+reveal_type(b)  # revealed: Point
+b = replace(a, x=3)
+reveal_type(b)  # revealed: Point
+```
+
+## Version support check
+
+It is not present in Python < 3.13
+
+```toml
+[environment]
+python-version = "3.12"
+```
+
+```py
+from copy import replace  # error: [unresolved-import]
+```

crates/ty_python_semantic/src/types/class.rs

@@ -1735,6 +1735,29 @@ impl<'db> ClassLiteral<'db> {
                     .place
                     .ignore_possibly_unbound()
             }
+            (CodeGeneratorKind::DataclassLike, "__replace__") => {
+                if Program::get(db).python_version(db) < PythonVersion::PY313 {
+                    return None;
+                }
+
+                Some(CallableType::function_like(
+                    db,
+                    Signature::new(
+                        Parameters::new([
+                            Parameter::positional_or_keyword(Name::new_static("self"))
+                                .with_annotated_type(Type::instance(
+                                    db,
+                                    self.apply_optional_specialization(db, specialization),
+                                )),
+                            // TODO
+                        ]),
+                        Some(Type::instance(
+                            db,
+                            self.apply_optional_specialization(db, specialization),
+                        )),
+                    ),
+                ))
+            }
             (CodeGeneratorKind::DataclassLike, "__setattr__") => {
                 if has_dataclass_param(DataclassParams::FROZEN) {
                     let signature = Signature::new(