From b949bb1b787dd1a37fc79837c7dfa18421521957 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Fri, 17 Jul 2020 18:59:07 +0100
Subject: [PATCH 1/5] CLN: consistent signatures for equals methods

---
 pandas/_libs/sparse.pyx             |  4 ++--
 pandas/core/arrays/base.py          |  2 +-
 pandas/core/arrays/categorical.py   |  4 ++--
 pandas/core/generic.py              |  2 +-
 pandas/core/indexes/category.py     |  2 +-
 pandas/core/indexes/datetimelike.py |  2 +-
 pandas/core/indexes/interval.py     |  2 +-
 pandas/core/indexes/multi.py        |  2 +-
 pandas/core/indexes/range.py        |  2 +-
 pandas/core/internals/managers.py   | 14 ++++++++++++--
 10 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/pandas/_libs/sparse.pyx b/pandas/_libs/sparse.pyx
index 7c9575d921dc9..d79db86685ac7 100644
--- a/pandas/_libs/sparse.pyx
+++ b/pandas/_libs/sparse.pyx
@@ -94,7 +94,7 @@ cdef class IntIndex(SparseIndex):
         if not monotonic:
             raise ValueError("Indices must be strictly increasing")
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         if not isinstance(other, IntIndex):
             return False
 
@@ -390,7 +390,7 @@ cdef class BlockIndex(SparseIndex):
             if blengths[i] == 0:
                 raise ValueError(f'Zero-length block {i}')
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         if not isinstance(other, BlockIndex):
             return False
 
diff --git a/pandas/core/arrays/base.py b/pandas/core/arrays/base.py
index 2553a65aed07b..55af2fc8281b7 100644
--- a/pandas/core/arrays/base.py
+++ b/pandas/core/arrays/base.py
@@ -742,7 +742,7 @@ def searchsorted(self, value, side="left", sorter=None):
         arr = self.astype(object)
         return arr.searchsorted(value, side=side, sorter=sorter)
 
-    def equals(self, other: "ExtensionArray") -> bool:
+    def equals(self, other: Any) -> bool:
         """
         Return if another array is equivalent to this array.
 
diff --git a/pandas/core/arrays/categorical.py b/pandas/core/arrays/categorical.py
index db9cfd9d7fc59..607dc91298e81 100644
--- a/pandas/core/arrays/categorical.py
+++ b/pandas/core/arrays/categorical.py
@@ -2,7 +2,7 @@
 from functools import partial
 import operator
 from shutil import get_terminal_size
-from typing import Dict, Hashable, List, Type, Union, cast
+from typing import Any, Dict, Hashable, List, Type, Union, cast
 from warnings import warn
 
 import numpy as np
@@ -2242,7 +2242,7 @@ def _from_factorized(cls, uniques, original):
             original.categories.take(uniques), dtype=original.dtype
         )
 
-    def equals(self, other):
+    def equals(self, other: Any) -> bool:
         """
         Returns True if categorical arrays are equal.
 
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index e46fde1f59f16..0eb235b110ca6 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -1195,7 +1195,7 @@ def _indexed_same(self, other) -> bool:
             self._get_axis(a).equals(other._get_axis(a)) for a in self._AXIS_ORDERS
         )
 
-    def equals(self, other):
+    def equals(self, other: Any) -> bool:
         """
         Test whether two objects contain the same elements.
 
diff --git a/pandas/core/indexes/category.py b/pandas/core/indexes/category.py
index b0b008de69a94..5d5cb54a3bab8 100644
--- a/pandas/core/indexes/category.py
+++ b/pandas/core/indexes/category.py
@@ -290,7 +290,7 @@ def _is_dtype_compat(self, other) -> bool:
 
         return other
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         """
         Determine if two CategoricalIndex objects contain the same elements.
 
diff --git a/pandas/core/indexes/datetimelike.py b/pandas/core/indexes/datetimelike.py
index 15a7e25238983..65b3eb4b9eb2b 100644
--- a/pandas/core/indexes/datetimelike.py
+++ b/pandas/core/indexes/datetimelike.py
@@ -126,7 +126,7 @@ def __array_wrap__(self, result, context=None):
 
     # ------------------------------------------------------------------------
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         """
         Determines if two Index objects contain the same elements.
         """
diff --git a/pandas/core/indexes/interval.py b/pandas/core/indexes/interval.py
index 9548ebbd9c3b2..ab9d42f444baa 100644
--- a/pandas/core/indexes/interval.py
+++ b/pandas/core/indexes/interval.py
@@ -1005,7 +1005,7 @@ def _format_space(self) -> str:
     def argsort(self, *args, **kwargs) -> np.ndarray:
         return np.lexsort((self.right, self.left))
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         """
         Determines if two IntervalIndex objects contain the same elements.
         """
diff --git a/pandas/core/indexes/multi.py b/pandas/core/indexes/multi.py
index 235da89083d0a..a9676fe656cba 100644
--- a/pandas/core/indexes/multi.py
+++ b/pandas/core/indexes/multi.py
@@ -3204,7 +3204,7 @@ def truncate(self, before=None, after=None):
             verify_integrity=False,
         )
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         """
         Determines if two MultiIndex objects have the same labeling information
         (the levels themselves do not necessarily have to be the same)
diff --git a/pandas/core/indexes/range.py b/pandas/core/indexes/range.py
index e5e98039ff77b..c0f55991610da 100644
--- a/pandas/core/indexes/range.py
+++ b/pandas/core/indexes/range.py
@@ -445,7 +445,7 @@ def argsort(self, *args, **kwargs) -> np.ndarray:
         else:
             return np.arange(len(self) - 1, -1, -1)
 
-    def equals(self, other) -> bool:
+    def equals(self, other: Any) -> bool:
         """
         Determines if two Index objects contain the same elements.
         """
diff --git a/pandas/core/internals/managers.py b/pandas/core/internals/managers.py
index d5947726af7fd..4c80e04bd1479 100644
--- a/pandas/core/internals/managers.py
+++ b/pandas/core/internals/managers.py
@@ -2,7 +2,17 @@
 import itertools
 import operator
 import re
-from typing import DefaultDict, Dict, List, Optional, Sequence, Tuple, TypeVar, Union
+from typing import (
+    Any,
+    DefaultDict,
+    Dict,
+    List,
+    Optional,
+    Sequence,
+    Tuple,
+    TypeVar,
+    Union,
+)
 import warnings
 
 import numpy as np
@@ -1415,7 +1425,7 @@ def take(self, indexer, axis: int = 1, verify: bool = True, convert: bool = True
             new_axis=new_labels, indexer=indexer, axis=axis, allow_dups=True
         )
 
-    def equals(self, other: "BlockManager") -> bool:
+    def equals(self, other: Any) -> bool:
         self_axes, other_axes = self.axes, other.axes
         if len(self_axes) != len(other_axes):
             return False

From 015e2b72b747c854062d2d776732190442aa1f73 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sat, 8 Aug 2020 18:56:15 +0100
Subject: [PATCH 2/5] Any > object for method body checking

---
 pandas/_libs/sparse.pyx                       |  4 ++--
 pandas/core/arrays/base.py                    |  7 ++++---
 pandas/core/arrays/categorical.py             |  8 +++++---
 pandas/core/generic.py                        |  4 +++-
 pandas/core/indexes/base.py                   |  3 ++-
 pandas/core/indexes/category.py               |  2 +-
 pandas/core/indexes/datetimelike.py           |  6 +++---
 pandas/core/indexes/interval.py               |  7 ++++---
 pandas/core/indexes/multi.py                  | 11 +++++------
 pandas/core/indexes/range.py                  |  2 +-
 pandas/core/internals/managers.py             | 17 +++++------------
 pandas/tests/plotting/common.py               |  1 +
 pandas/tests/series/indexing/test_datetime.py |  1 +
 13 files changed, 37 insertions(+), 36 deletions(-)

diff --git a/pandas/_libs/sparse.pyx b/pandas/_libs/sparse.pyx
index 7bcf25e0c5a43..0c3d8915b749b 100644
--- a/pandas/_libs/sparse.pyx
+++ b/pandas/_libs/sparse.pyx
@@ -103,7 +103,7 @@ cdef class IntIndex(SparseIndex):
         if not monotonic:
             raise ValueError("Indices must be strictly increasing")
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         if not isinstance(other, IntIndex):
             return False
 
@@ -399,7 +399,7 @@ cdef class BlockIndex(SparseIndex):
             if blengths[i] == 0:
                 raise ValueError(f'Zero-length block {i}')
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         if not isinstance(other, BlockIndex):
             return False
 
diff --git a/pandas/core/arrays/base.py b/pandas/core/arrays/base.py
index 0c15d71d99105..c203b2f30e07c 100644
--- a/pandas/core/arrays/base.py
+++ b/pandas/core/arrays/base.py
@@ -7,7 +7,7 @@
    without warning.
 """
 import operator
-from typing import Any, Callable, Dict, Optional, Sequence, Tuple, Union
+from typing import Any, Callable, Dict, Optional, Sequence, Tuple, Union, cast
 
 import numpy as np
 
@@ -742,7 +742,7 @@ def searchsorted(self, value, side="left", sorter=None):
         arr = self.astype(object)
         return arr.searchsorted(value, side=side, sorter=sorter)
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Return if another array is equivalent to this array.
 
@@ -762,7 +762,8 @@ def equals(self, other: Any) -> bool:
         """
         if not type(self) == type(other):
             return False
-        elif not self.dtype == other.dtype:
+        other = cast(ExtensionArray, other)
+        if not self.dtype == other.dtype:
             return False
         elif not len(self) == len(other):
             return False
diff --git a/pandas/core/arrays/categorical.py b/pandas/core/arrays/categorical.py
index 1965ea21bcb35..a28b341669918 100644
--- a/pandas/core/arrays/categorical.py
+++ b/pandas/core/arrays/categorical.py
@@ -2,7 +2,7 @@
 from functools import partial
 import operator
 from shutil import get_terminal_size
-from typing import Any, Dict, Hashable, List, Type, Union, cast
+from typing import Dict, Hashable, List, Type, Union, cast
 from warnings import warn
 
 import numpy as np
@@ -2242,7 +2242,7 @@ def _from_factorized(cls, uniques, original):
             original.categories.take(uniques), dtype=original.dtype
         )
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Returns True if categorical arrays are equal.
 
@@ -2254,7 +2254,9 @@ def equals(self, other: Any) -> bool:
         -------
         bool
         """
-        if self.is_dtype_equal(other):
+        if not isinstance(other, Categorical):
+            return False
+        elif self.is_dtype_equal(other):
             if self.categories.equals(other.categories):
                 # fastpath to avoid re-coding
                 other_codes = other._codes
diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index ef1296309d0ce..6546621e28a65 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -22,6 +22,7 @@
     Tuple,
     Type,
     Union,
+    cast,
 )
 import warnings
 import weakref
@@ -1195,7 +1196,7 @@ def _indexed_same(self, other) -> bool:
             self._get_axis(a).equals(other._get_axis(a)) for a in self._AXIS_ORDERS
         )
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Test whether two objects contain the same elements.
 
@@ -1275,6 +1276,7 @@ def equals(self, other: Any) -> bool:
         """
         if not (isinstance(other, type(self)) or isinstance(self, type(other))):
             return False
+        other = cast(NDFrame, other)
         return self._mgr.equals(other._mgr)
 
     # -------------------------------------------------------------------------
diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index bfdfbd35f27ad..91364da4f9327 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -4168,7 +4168,7 @@ def putmask(self, mask, value):
             # coerces to object
             return self.astype(object).putmask(mask, value)
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Determine if two Index object are equal.
 
@@ -4242,6 +4242,7 @@ def equals(self, other: Any) -> bool:
             and type(other) is not type(self)
             and other.equals is not self.equals
         ):
+            breakpoint()
             return other.equals(self)
 
         return array_equivalent(self._values, other._values)
diff --git a/pandas/core/indexes/category.py b/pandas/core/indexes/category.py
index 295fa4d163400..4990e6a8e20e9 100644
--- a/pandas/core/indexes/category.py
+++ b/pandas/core/indexes/category.py
@@ -290,7 +290,7 @@ def _is_dtype_compat(self, other) -> bool:
 
         return other
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Determine if two CategoricalIndex objects contain the same elements.
 
diff --git a/pandas/core/indexes/datetimelike.py b/pandas/core/indexes/datetimelike.py
index d8e743e034c12..47cbe11eac3ee 100644
--- a/pandas/core/indexes/datetimelike.py
+++ b/pandas/core/indexes/datetimelike.py
@@ -24,7 +24,7 @@
     is_scalar,
 )
 from pandas.core.dtypes.concat import concat_compat
-from pandas.core.dtypes.generic import ABCIndex, ABCIndexClass, ABCSeries
+from pandas.core.dtypes.generic import ABCIndex, ABCSeries
 
 from pandas.core import algorithms
 from pandas.core.arrays import DatetimeArray, PeriodArray, TimedeltaArray
@@ -130,14 +130,14 @@ def __array_wrap__(self, result, context=None):
 
     # ------------------------------------------------------------------------
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Determines if two Index objects contain the same elements.
         """
         if self.is_(other):
             return True
 
-        if not isinstance(other, ABCIndexClass):
+        if not isinstance(other, Index):
             return False
         elif not isinstance(other, type(self)):
             try:
diff --git a/pandas/core/indexes/interval.py b/pandas/core/indexes/interval.py
index ab9d42f444baa..e8d0a44324cc5 100644
--- a/pandas/core/indexes/interval.py
+++ b/pandas/core/indexes/interval.py
@@ -1005,19 +1005,20 @@ def _format_space(self) -> str:
     def argsort(self, *args, **kwargs) -> np.ndarray:
         return np.lexsort((self.right, self.left))
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Determines if two IntervalIndex objects contain the same elements.
         """
         if self.is_(other):
             return True
 
-        # if we can coerce to an II
-        # then we can compare
+        # if we can coerce to an IntervalIndex then we can compare
         if not isinstance(other, IntervalIndex):
             if not is_interval_dtype(other):
                 return False
             other = Index(other)
+            if not isinstance(other, IntervalIndex):
+                return False
 
         return (
             self.left.equals(other.left)
diff --git a/pandas/core/indexes/multi.py b/pandas/core/indexes/multi.py
index be332a7061ae1..ed4da50201c0d 100644
--- a/pandas/core/indexes/multi.py
+++ b/pandas/core/indexes/multi.py
@@ -3205,7 +3205,7 @@ def truncate(self, before=None, after=None):
             verify_integrity=False,
         )
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Determines if two MultiIndex objects have the same labeling information
         (the levels themselves do not necessarily have to be the same)
@@ -3248,11 +3248,10 @@ def equals(self, other: Any) -> bool:
                 np.asarray(other.levels[i]._values), other_codes, allow_fill=False
             )
 
-            # since we use NaT both datetime64 and timedelta64
-            # we can have a situation where a level is typed say
-            # timedelta64 in self (IOW it has other values than NaT)
-            # but types datetime64 in other (where its all NaT)
-            # but these are equivalent
+            # since we use NaT both datetime64 and timedelta64 we can have a
+            # situation where a level is typed say timedelta64 in self (IOW it
+            # has other values than NaT) but types datetime64 in other (where
+            # its all NaT) but these are equivalent
             if len(self_values) == 0 and len(other_values) == 0:
                 continue
 
diff --git a/pandas/core/indexes/range.py b/pandas/core/indexes/range.py
index 9e0bead39a855..d035cee7c3bc9 100644
--- a/pandas/core/indexes/range.py
+++ b/pandas/core/indexes/range.py
@@ -434,7 +434,7 @@ def argsort(self, *args, **kwargs) -> np.ndarray:
         else:
             return np.arange(len(self) - 1, -1, -1)
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
         """
         Determines if two Index objects contain the same elements.
         """
diff --git a/pandas/core/internals/managers.py b/pandas/core/internals/managers.py
index a742de36c7bbe..371b721f08b27 100644
--- a/pandas/core/internals/managers.py
+++ b/pandas/core/internals/managers.py
@@ -2,17 +2,7 @@
 import itertools
 import operator
 import re
-from typing import (
-    Any,
-    DefaultDict,
-    Dict,
-    List,
-    Optional,
-    Sequence,
-    Tuple,
-    TypeVar,
-    Union,
-)
+from typing import DefaultDict, Dict, List, Optional, Sequence, Tuple, TypeVar, Union
 import warnings
 
 import numpy as np
@@ -1447,7 +1437,10 @@ def take(self, indexer, axis: int = 1, verify: bool = True, convert: bool = True
             new_axis=new_labels, indexer=indexer, axis=axis, allow_dups=True
         )
 
-    def equals(self, other: Any) -> bool:
+    def equals(self, other: object) -> bool:
+        if not isinstance(other, BlockManager):
+            return False
+
         self_axes, other_axes = self.axes, other.axes
         if len(self_axes) != len(other_axes):
             return False
diff --git a/pandas/tests/plotting/common.py b/pandas/tests/plotting/common.py
index 3b1ff233c5ec1..289809fad61fa 100644
--- a/pandas/tests/plotting/common.py
+++ b/pandas/tests/plotting/common.py
@@ -13,6 +13,7 @@
 from pandas import DataFrame, Series
 import pandas._testing as tm
 
+
 """
 This is a common base class used for various plotting tests
 """
diff --git a/pandas/tests/series/indexing/test_datetime.py b/pandas/tests/series/indexing/test_datetime.py
index 088f8681feb99..19d5dfa3b3900 100644
--- a/pandas/tests/series/indexing/test_datetime.py
+++ b/pandas/tests/series/indexing/test_datetime.py
@@ -11,6 +11,7 @@
 from pandas import DataFrame, DatetimeIndex, NaT, Series, Timestamp, date_range
 import pandas._testing as tm
 
+
 """
 Also test support for datetime64[ns] in Series / DataFrame
 """

From a460526f885da5b4fa13c0ca22aea31c987987d5 Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sat, 8 Aug 2020 20:05:19 +0100
Subject: [PATCH 3/5] isort fixup

---
 pandas/tests/plotting/common.py               | 1 -
 pandas/tests/series/indexing/test_datetime.py | 1 -
 2 files changed, 2 deletions(-)

diff --git a/pandas/tests/plotting/common.py b/pandas/tests/plotting/common.py
index 289809fad61fa..3b1ff233c5ec1 100644
--- a/pandas/tests/plotting/common.py
+++ b/pandas/tests/plotting/common.py
@@ -13,7 +13,6 @@
 from pandas import DataFrame, Series
 import pandas._testing as tm
 
-
 """
 This is a common base class used for various plotting tests
 """
diff --git a/pandas/tests/series/indexing/test_datetime.py b/pandas/tests/series/indexing/test_datetime.py
index 19d5dfa3b3900..088f8681feb99 100644
--- a/pandas/tests/series/indexing/test_datetime.py
+++ b/pandas/tests/series/indexing/test_datetime.py
@@ -11,7 +11,6 @@
 from pandas import DataFrame, DatetimeIndex, NaT, Series, Timestamp, date_range
 import pandas._testing as tm
 
-
 """
 Also test support for datetime64[ns] in Series / DataFrame
 """

From 4aea1c7f59034f7761df7191a6daa9c8a6eb3b9b Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Sat, 8 Aug 2020 20:10:32 +0100
Subject: [PATCH 4/5] remove breakpoint

---
 pandas/core/indexes/base.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/core/indexes/base.py b/pandas/core/indexes/base.py
index 55fb8456c4bc1..6c3fc9f848d50 100644
--- a/pandas/core/indexes/base.py
+++ b/pandas/core/indexes/base.py
@@ -4242,7 +4242,6 @@ def equals(self, other: object) -> bool:
             and type(other) is not type(self)
             and other.equals is not self.equals
         ):
-            breakpoint()
             return other.equals(self)
 
         return array_equivalent(self._values, other._values)

From f0e63277f06ef7d19ec89bc7bb69aaf0382c011e Mon Sep 17 00:00:00 2001
From: Simon Hawkins <simonjayhawkins@gmail.com>
Date: Mon, 10 Aug 2020 15:18:04 +0100
Subject: [PATCH 5/5] use is_dtype_equal

---
 pandas/core/arrays/base.py | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/pandas/core/arrays/base.py b/pandas/core/arrays/base.py
index c203b2f30e07c..d85647edc3b81 100644
--- a/pandas/core/arrays/base.py
+++ b/pandas/core/arrays/base.py
@@ -20,7 +20,12 @@
 from pandas.util._validators import validate_fillna_kwargs
 
 from pandas.core.dtypes.cast import maybe_cast_to_extension_array
-from pandas.core.dtypes.common import is_array_like, is_list_like, pandas_dtype
+from pandas.core.dtypes.common import (
+    is_array_like,
+    is_dtype_equal,
+    is_list_like,
+    pandas_dtype,
+)
 from pandas.core.dtypes.dtypes import ExtensionDtype
 from pandas.core.dtypes.generic import ABCDataFrame, ABCIndexClass, ABCSeries
 from pandas.core.dtypes.missing import isna
@@ -763,7 +768,7 @@ def equals(self, other: object) -> bool:
         if not type(self) == type(other):
             return False
         other = cast(ExtensionArray, other)
-        if not self.dtype == other.dtype:
+        if not is_dtype_equal(self.dtype, other.dtype):
             return False
         elif not len(self) == len(other):
             return False