From 961972e00461e9b6b38c8f3d4395748540c630c8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Torsten=20W=C3=B6rtwein?= <twoertwein@gmail.com>
Date: Tue, 31 May 2022 21:08:45 -0400
Subject: [PATCH] TYP: annotate two decorators

---
 pandas/core/computation/align.py | 5 ++++-
 pandas/core/reshape/merge.py     | 4 +++-
 pandas/util/_decorators.py       | 2 +-
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/pandas/core/computation/align.py b/pandas/core/computation/align.py
index f14882227ddd9..2e7a0f842ee6d 100644
--- a/pandas/core/computation/align.py
+++ b/pandas/core/computation/align.py
@@ -9,6 +9,7 @@
 )
 from typing import (
     TYPE_CHECKING,
+    Callable,
     Sequence,
 )
 import warnings
@@ -28,6 +29,8 @@
 from pandas.core.computation.common import result_type_many
 
 if TYPE_CHECKING:
+    from pandas._typing import F
+
     from pandas.core.generic import NDFrame
     from pandas.core.indexes.api import Index
 
@@ -62,7 +65,7 @@ def _any_pandas_objects(terms) -> bool:
     return any(isinstance(term.value, PandasObject) for term in terms)
 
 
-def _filter_special_cases(f):
+def _filter_special_cases(f) -> Callable[[F], F]:
     @wraps(f)
     def wrapper(terms):
         # single unary operand
diff --git a/pandas/core/reshape/merge.py b/pandas/core/reshape/merge.py
index 4227d43c459d0..5f108c26d239a 100644
--- a/pandas/core/reshape/merge.py
+++ b/pandas/core/reshape/merge.py
@@ -162,7 +162,9 @@ def _groupby_and_merge(by, left: DataFrame, right: DataFrame, merge_pieces):
                 lcols = lhs.columns.tolist()
                 cols = lcols + [r for r in right.columns if r not in set(lcols)]
                 merged = lhs.reindex(columns=cols)
-                merged.index = range(len(merged))
+                # error: Incompatible types in assignment (expression has type
+                # "range", variable has type "Index")
+                merged.index = range(len(merged))  # type: ignore[assignment]
                 pieces.append(merged)
                 continue
 
diff --git a/pandas/util/_decorators.py b/pandas/util/_decorators.py
index 6f8889e9017d0..0f15511e491cc 100644
--- a/pandas/util/_decorators.py
+++ b/pandas/util/_decorators.py
@@ -323,7 +323,7 @@ def wrapper(*args, **kwargs):
 
 def rewrite_axis_style_signature(
     name: str, extra_params: list[tuple[str, Any]]
-) -> Callable[..., Any]:
+) -> Callable[[F], F]:
     def decorate(func: F) -> F:
         @wraps(func)
         def wrapper(*args, **kwargs) -> Callable[..., Any]: