Solve a followup problem without a tracking issue

Author: A5rocks

mypy/typeops.py

@@ -458,19 +458,17 @@ def callable_corresponding_argument(
     if by_name is not None and by_pos is not None:
         if by_name == by_pos:
             return by_name
-        # If we're dealing with an optional pos-only and an optional
-        # name-only arg, merge them.  This is the case for all functions
-        # taking both *args and **args, or a pair of functions like so:
+        # If we're dealing with an optional pos and an optional
+        # name arg, merge them.  This is the case for all functions
+        # taking both *args and **args, or a functions like so:
 
         # def right(a: int = ...) -> None: ...
-        # def left(__a: int = ..., *, a: int = ...) -> None: ...
+        # def left1(__a: int = ..., *, a: int = ...) -> None: ...
+        # def left2(x: int = ..., a: int = ...) -> None: ...
+
         from mypy.meet import meet_types
 
-        if (
-            not (by_name.required or by_pos.required)
-            and by_pos.name is None
-            and by_name.pos is None
-        ):
+        if not (by_name.required or by_pos.required):
             return FormalArgument(
                 by_name.name, by_pos.pos, meet_types(by_pos.typ, by_name.typ), False
             )

test-data/unit/check-overloading.test

@@ -6784,3 +6784,18 @@ def set() -> None:
 def set(*args: object, **kw: int) -> None:
     pass
 [builtins fixtures/tuple.pyi]
+
+[case testOverloadWithTwoRelevantOptionalArgs]
+from typing import overload
+
+@overload
+def set(year: int) -> None:
+    ...
+
+@overload
+def set() -> None:
+    ...
+
+# no error:
+def set(x: int = 42, year: int = 42) -> None:
+    pass