Fixes union order

Author: sobolevn

classes/contrib/mypy/typeops/call_signatures.py

@@ -3,10 +3,16 @@
 from mypy.messages import callable_name
 from mypy.plugin import MethodSigContext
 from mypy.subtypes import is_subtype
-from mypy.typeops import get_type_vars, make_simplified_union
+from mypy.typeops import get_type_vars
 from mypy.types import CallableType, Instance, ProperType
 from mypy.types import Type as MypyType
-from mypy.types import TypeVarDef, TypeVarId, TypeVarType, union_items
+from mypy.types import (
+    TypeVarDef,
+    TypeVarId,
+    TypeVarType,
+    UnionType,
+    union_items,
+)
 from typing_extensions import Final, final
 
 from classes.contrib.mypy.typeops import type_loader
@@ -69,7 +75,10 @@ def _infer_type_var(
                 self._ctx,
             ))
 
-        instance_type = make_simplified_union(instance_types)
+        # We use `make_union` instead of `make_simplified_union`
+        # to show all instance items in the output,
+        # for example `Union[int, float]` won't be converted into `float`.
+        instance_type = UnionType.make_union(sorted(instance_types))
         if not is_subtype(passed_type, instance_type):
             # Let's explain: what happens here?
             # We need to enforce
@@ -92,9 +101,9 @@ def _infer_regular(self, first_arg: MypyType) -> CallableType:
                 self._ctx,
                 should_replace_typevars=True,
             )
-        self._signature.arg_types[0] = make_simplified_union(
+        self._signature.arg_types[0] = UnionType.make_union(sorted(
             list(filter(None, [self._instance_type, supports_type])),
-        )
+        ))
         return self._signature
 
 

classes/contrib/mypy/typeops/instance_args.py

@@ -1,7 +1,6 @@
 from typing import List, Union
 
 from mypy.plugin import FunctionContext, MethodContext
-from mypy.typeops import make_simplified_union
 from mypy.types import AnyType, Instance, LiteralType, TupleType
 from mypy.types import Type as MypyType
 from mypy.types import TypeVarType, UnboundType, UninhabitedType
@@ -32,7 +31,7 @@ def add_unique(
         lambda type_: not isinstance(type_, _TYPES_TO_FILTER_OUT),
         [new_instance_type, existing_instance_type],
     )))
-    return make_simplified_union(unified)
+    return UnionType.make_union(sorted(unified))
 
 
 def mutate_typeclass_def(