From 8be97f8f3ce2db4ed85db2c6c68d8c39508df3a6 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 14:34:23 +0200
Subject: [PATCH 01/51] Fix numpy boolean subtraction error in Series.diff

Numpy no longer allows subtraction of boolean values. Not sure if Numpy version checking should be done before this code...
Note: I haven't actually run this code, feel free to check it, but should be correct.

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-46-3da3b949c6bd> in <module>
      1 data = pd.Series([0,-1,-2,-3,-4,-3,-2,-1,0,-1,-1,0,-1,-2,-3,-2,0])
      2 filtered = data.between(-2,0, inclusive = True)
----> 3 filtered.diff()
      4 print(filtered)

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\series.py in diff(self, periods)
   2191         dtype: float64
   2192         """
-> 2193         result = algorithms.diff(com.values_from_object(self), periods)
   2194         return self._constructor(result, index=self.index).__finalize__(self)
   2195

~\AppData\Local\Continuum\anaconda3\lib\site-packages\pandas\core\algorithms.py in diff(arr, n, axis)
   1817             out_arr[res_indexer] = result
   1818         else:
-> 1819             out_arr[res_indexer] = arr[res_indexer] - arr[lag_indexer]
   1820
   1821     if is_timedelta:

TypeError: numpy boolean subtract, the `-` operator, is deprecated, use the bitwise_xor, the `^` operator, or the logical_xor function instead.
---
 pandas/core/algorithms.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index 21d12d02c9008..70971a5f8aef7 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1933,6 +1933,7 @@ def diff(arr, n, axis=0):
 
     elif is_bool_dtype(dtype):
         dtype = np.object_
+        is_bool = True
 
     elif is_integer_dtype(dtype):
         dtype = np.float64
@@ -1972,6 +1973,8 @@ def diff(arr, n, axis=0):
             result = res - lag
             result[mask] = na
             out_arr[res_indexer] = result
+        elif is_bool:
+            out_arr[res_indexer] = arr[res_indexer] ^ arr[lag_indexer]
         else:
             out_arr[res_indexer] = arr[res_indexer] - arr[lag_indexer]
 

From 7c982d20a2fc61a472aa1be134aa69e04a2537a9 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 15:18:53 +0200
Subject: [PATCH 02/51] Added is_bool outside if function

---
 pandas/core/algorithms.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index 70971a5f8aef7..6e1c2f1c178b8 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1925,6 +1925,7 @@ def diff(arr, n, axis=0):
     dtype = arr.dtype
 
     is_timedelta = False
+    is_bool = False
     if needs_i8_conversion(arr):
         dtype = np.float64
         arr = arr.view("i8")

From 45f9c60fd0eb069d54b0ee7e6845d91a91baf6fe Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 15:56:45 +0200
Subject: [PATCH 03/51] Added test_diff function

---
 pandas/tests/series/test_diff.py | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 pandas/tests/series/test_diff.py

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
new file mode 100644
index 0000000000000..d6c443d2c5b62
--- /dev/null
+++ b/pandas/tests/series/test_diff.py
@@ -0,0 +1,17 @@
+from pandas import (
+    Series
+)
+
+from numpy import nan
+
+def test_diff():
+    data = Series([0,-1,-2,-3,-4,-3,-2,-1,0,-1,-1,0,-1,-2,-3,-2,0])
+
+    filtered = data.between(-2,0, inclusive = True)
+    diff_boolean = filtered.diff()
+    expected_boolean = Series([nan, False, False, True, False, False, True, False, False, False, False, False, False, False, True, True, False])
+    assert diff_boolean.equals(expected_boolean)
+
+    diff_data = data.diff()
+    expected_data = Series([nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 0.0, 1.0, -1.0, -1.0, -1.0, 1.0, 2.0])
+    assert diff_data.equals(expected_data)

From 83907a2f1cb5ec2a4e04f22196af7b5fe41e6f22 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 15:58:40 +0200
Subject: [PATCH 04/51] Update test_diff.py

---
 pandas/tests/series/test_diff.py | 2 --
 1 file changed, 2 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index d6c443d2c5b62..404688b673de6 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -6,12 +6,10 @@
 
 def test_diff():
     data = Series([0,-1,-2,-3,-4,-3,-2,-1,0,-1,-1,0,-1,-2,-3,-2,0])
-
     filtered = data.between(-2,0, inclusive = True)
     diff_boolean = filtered.diff()
     expected_boolean = Series([nan, False, False, True, False, False, True, False, False, False, False, False, False, False, True, True, False])
     assert diff_boolean.equals(expected_boolean)
-
     diff_data = data.diff()
     expected_data = Series([nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 0.0, 1.0, -1.0, -1.0, -1.0, 1.0, 2.0])
     assert diff_data.equals(expected_data)

From 6c3875e5b640e2eee9139737864171bcac7a10b6 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 16:04:56 +0200
Subject: [PATCH 05/51] Changing style to match PEP

---
 pandas/tests/series/test_diff.py | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 404688b673de6..8eeed64ec432a 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -4,12 +4,21 @@
 
 from numpy import nan
 
+
 def test_diff():
-    data = Series([0,-1,-2,-3,-4,-3,-2,-1,0,-1,-1,0,-1,-2,-3,-2,0])
-    filtered = data.between(-2,0, inclusive = True)
+    data = Series(
+        [0, -1, -2, -3, -4, -3, -2, -1, 0, -1, -1, 0, -1, -2, -3, -2, 0]
+    )
+    filtered = data.between(-2, 0, inclusive=True)
     diff_boolean = filtered.diff()
-    expected_boolean = Series([nan, False, False, True, False, False, True, False, False, False, False, False, False, False, True, True, False])
+    expected_boolean = Series(
+        [nan, False, False, True, False, False, True, False, False, \
+         False, False, False, False, False, True, True, False]
+    )
     assert diff_boolean.equals(expected_boolean)
     diff_data = data.diff()
-    expected_data = Series([nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, -1.0, 0.0, 1.0, -1.0, -1.0, -1.0, 1.0, 2.0])
+    expected_data = Series(
+        [nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, \
+         -1.0, 0.0, 1.0, -1.0, -1.0, -1.0, 1.0, 2.0]
+    )
     assert diff_data.equals(expected_data)

From ecf1c04a27e73514ec7e6fc4e6518c6e78a69530 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 16:06:48 +0200
Subject: [PATCH 06/51] Update test_diff.py

---
 pandas/tests/series/test_diff.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 8eeed64ec432a..564f45f4c5bc6 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -12,13 +12,13 @@ def test_diff():
     filtered = data.between(-2, 0, inclusive=True)
     diff_boolean = filtered.diff()
     expected_boolean = Series(
-        [nan, False, False, True, False, False, True, False, False, \
+        [nan, False, False, True, False, False, True, False, False,
          False, False, False, False, False, True, True, False]
     )
     assert diff_boolean.equals(expected_boolean)
     diff_data = data.diff()
     expected_data = Series(
-        [nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0, \
+        [nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0,
          -1.0, 0.0, 1.0, -1.0, -1.0, -1.0, 1.0, 2.0]
     )
     assert diff_data.equals(expected_data)

From dd8ff9839fa515b8e04dd56b55ed40081127d62a Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 5 Aug 2019 17:04:48 +0200
Subject: [PATCH 07/51] Using tm to assert series differences

---
 pandas/tests/series/test_diff.py | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 564f45f4c5bc6..9f6545c5cecbe 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -1,24 +1,23 @@
-from pandas import (
-    Series
-)
-
 from numpy import nan
+from pandas import Series
+import pandas.util.testing as tm
 
 
 def test_diff():
+    '''
+    Tests the pd.Series diff function on boolean series.
+    '''
     data = Series(
-        [0, -1, -2, -3, -4, -3, -2, -1, 0, -1, -1, 0, -1, -2, -3, -2, 0]
+        [0, -1, -2, -3, -4, -3, -2, -1, 0]
     )
     filtered = data.between(-2, 0, inclusive=True)
     diff_boolean = filtered.diff()
     expected_boolean = Series(
-        [nan, False, False, True, False, False, True, False, False,
-         False, False, False, False, False, True, True, False]
+        [nan, False, False, True, False, False, True, False, False]
     )
-    assert diff_boolean.equals(expected_boolean)
+    tm.assert_series_equal(diff_boolean, expected_boolean)
     diff_data = data.diff()
     expected_data = Series(
-        [nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0,
-         -1.0, 0.0, 1.0, -1.0, -1.0, -1.0, 1.0, 2.0]
+        [nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0]
     )
-    assert diff_data.equals(expected_data)
+    tm.assert_series_equal(diff_data, expected_data)

From e123486314f90a6ef129901114fbeb93283e5233 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 11:21:07 +0200
Subject: [PATCH 08/51] Added diff bug description to changelog

---
 doc/source/whatsnew/v0.25.1.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v0.25.1.rst b/doc/source/whatsnew/v0.25.1.rst
index 4d9ee4c676759..4b0358a893d15 100644
--- a/doc/source/whatsnew/v0.25.1.rst
+++ b/doc/source/whatsnew/v0.25.1.rst
@@ -153,7 +153,7 @@ ExtensionArray
 Other
 ^^^^^
 - Bug in :meth:`Series.replace` and :meth:`DataFrame.replace` when replacing timezone-aware timestamps using a dict-like replacer (:issue:`27720`)
--
+- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0
 -
 -
 

From 269d148d2f5d88b04d55badf1b5c41edadd33a58 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 11:31:48 +0200
Subject: [PATCH 09/51] Added issue number

---
 doc/source/whatsnew/v0.25.1.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v0.25.1.rst b/doc/source/whatsnew/v0.25.1.rst
index 4b0358a893d15..181b208d70d49 100644
--- a/doc/source/whatsnew/v0.25.1.rst
+++ b/doc/source/whatsnew/v0.25.1.rst
@@ -153,7 +153,7 @@ ExtensionArray
 Other
 ^^^^^
 - Bug in :meth:`Series.replace` and :meth:`DataFrame.replace` when replacing timezone-aware timestamps using a dict-like replacer (:issue:`27720`)
-- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0
+- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0 (:issue:`17294`)
 -
 -
 

From 3993206038774ae174d1dd7f35fc82df2b8f030e Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 12:15:18 +0200
Subject: [PATCH 10/51] Adding timeseries tests as well

---
 pandas/tests/series/test_diff.py | 82 +++++++++++++++++++++++---------
 1 file changed, 59 insertions(+), 23 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 9f6545c5cecbe..af2d078ed2d0c 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -1,23 +1,59 @@
-from numpy import nan
-from pandas import Series
-import pandas.util.testing as tm
-
-
-def test_diff():
-    '''
-    Tests the pd.Series diff function on boolean series.
-    '''
-    data = Series(
-        [0, -1, -2, -3, -4, -3, -2, -1, 0]
-    )
-    filtered = data.between(-2, 0, inclusive=True)
-    diff_boolean = filtered.diff()
-    expected_boolean = Series(
-        [nan, False, False, True, False, False, True, False, False]
-    )
-    tm.assert_series_equal(diff_boolean, expected_boolean)
-    diff_data = data.diff()
-    expected_data = Series(
-        [nan, -1.0, -1.0, -1.0, -1.0, 1.0, 1.0, 1.0, 1.0]
-    )
-    tm.assert_series_equal(diff_data, expected_data)
+from pandas import (
+    Series,
+    date_range,
+)
+from pandas.tests.series.common import TestData
+from pandas.core.indexes.timedeltas import TimedeltaIndex
+from pandas.util.testing import assert_series_equal
+
+class TestDiff(TestData):
+    def test_diff(self):
+        # Just run the function
+        self.ts.diff()
+
+        # int dtype
+        a = 10000000000000000
+        b = a + 1
+        s = Series([a, b])
+
+        rs = s.diff()
+        assert rs[1] == 1
+
+        # neg n
+        rs = self.ts.diff(-1)
+        xp = self.ts - self.ts.shift(-1)
+        assert_series_equal(rs, xp)
+
+        # 0
+        rs = self.ts.diff(0)
+        xp = self.ts - self.ts
+        assert_series_equal(rs, xp)
+
+        # datetime diff (GH3100)
+        s = Series(date_range("20130102", periods=5))
+        rs = s - s.shift(1)
+        xp = s.diff()
+        assert_series_equal(rs, xp)
+
+        # timedelta diff
+        nrs = rs - rs.shift(1)
+        nxp = xp.diff()
+        assert_series_equal(nrs, nxp)
+
+        # with tz
+        s = Series(
+            date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
+        )
+        result = s.diff()
+        assert_series_equal(
+            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
+        )
+
+        # boolean series
+        s = Series(
+            [False, True, True, False, False]
+        )
+        result = s.diff()
+        assert_series_equal(
+            result, Series[nan, True, False, True, False]
+        )

From b610dd9fec32d88a8653cd7f264c94498de51411 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 12:16:56 +0200
Subject: [PATCH 11/51] Removed test_diff, it is added to test_diff.py

I copied the data over to the other file, diff tests should be in one file and the boolean test cannot be added to this one as it is not a time series.
---
 pandas/tests/series/test_timeseries.py | 42 --------------------------
 1 file changed, 42 deletions(-)

diff --git a/pandas/tests/series/test_timeseries.py b/pandas/tests/series/test_timeseries.py
index d0ca5d82c6b33..fbe3f929cf5b5 100644
--- a/pandas/tests/series/test_timeseries.py
+++ b/pandas/tests/series/test_timeseries.py
@@ -355,48 +355,6 @@ def test_asfreq_datetimeindex_empty_series(self):
         )
         tm.assert_index_equal(expected.index, result.index)
 
-    def test_diff(self):
-        # Just run the function
-        self.ts.diff()
-
-        # int dtype
-        a = 10000000000000000
-        b = a + 1
-        s = Series([a, b])
-
-        rs = s.diff()
-        assert rs[1] == 1
-
-        # neg n
-        rs = self.ts.diff(-1)
-        xp = self.ts - self.ts.shift(-1)
-        assert_series_equal(rs, xp)
-
-        # 0
-        rs = self.ts.diff(0)
-        xp = self.ts - self.ts
-        assert_series_equal(rs, xp)
-
-        # datetime diff (GH3100)
-        s = Series(date_range("20130102", periods=5))
-        rs = s - s.shift(1)
-        xp = s.diff()
-        assert_series_equal(rs, xp)
-
-        # timedelta diff
-        nrs = rs - rs.shift(1)
-        nxp = xp.diff()
-        assert_series_equal(nrs, nxp)
-
-        # with tz
-        s = Series(
-            date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
-        )
-        result = s.diff()
-        assert_series_equal(
-            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
-        )
-
     def test_pct_change(self):
         rs = self.ts.pct_change(fill_method=None)
         assert_series_equal(rs, self.ts / self.ts.shift(1) - 1)

From 92075fbc3cec3426c71752d71ab6739e620cae5b Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 13:06:10 +0200
Subject: [PATCH 12/51] Removed too much code, importing nan again

---
 pandas/tests/series/test_diff.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index af2d078ed2d0c..dc77e15fdbec5 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -1,3 +1,4 @@
+from numpy import nan
 from pandas import (
     Series,
     date_range,

From 1b906575f2606a66e307c5bc99dcbb2de379b23e Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 13:08:38 +0200
Subject: [PATCH 13/51] STYLE: formatting...

---
 pandas/tests/series/test_diff.py | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index dc77e15fdbec5..1bb9c57701748 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -1,12 +1,10 @@
 from numpy import nan
-from pandas import (
-    Series,
-    date_range,
-)
+from pandas import Series, date_range
 from pandas.tests.series.common import TestData
 from pandas.core.indexes.timedeltas import TimedeltaIndex
 from pandas.util.testing import assert_series_equal
 
+
 class TestDiff(TestData):
     def test_diff(self):
         # Just run the function
@@ -51,10 +49,6 @@ def test_diff(self):
         )
 
         # boolean series
-        s = Series(
-            [False, True, True, False, False]
-        )
+        s = Series([False, True, True, False, False])
         result = s.diff()
-        assert_series_equal(
-            result, Series[nan, True, False, True, False]
-        )
+        assert_series_equal(result, Series[nan, True, False, True, False])

From 182cbc25b5535d65fd7284b95d4f893c6ea36782 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 13:37:34 +0200
Subject: [PATCH 14/51] Splitting into two functions

---
 pandas/tests/series/test_diff.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 1bb9c57701748..a37f64956f834 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -6,7 +6,7 @@
 
 
 class TestDiff(TestData):
-    def test_diff(self):
+    def test_ts_diff(self):
         # Just run the function
         self.ts.diff()
 
@@ -47,7 +47,8 @@ def test_diff(self):
         assert_series_equal(
             result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
         )
-
+        
+    def test_boolean_diff(self):
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()

From 3ba0958f98d15f8bf2a72a94a018400be9b8489b Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 13:48:35 +0200
Subject: [PATCH 15/51] Split into 3 functions

---
 pandas/tests/series/test_diff.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index a37f64956f834..692b0c5ae9c1a 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -27,7 +27,8 @@ def test_ts_diff(self):
         rs = self.ts.diff(0)
         xp = self.ts - self.ts
         assert_series_equal(rs, xp)
-
+        
+    def test_datetime_diff(self):
         # datetime diff (GH3100)
         s = Series(date_range("20130102", periods=5))
         rs = s - s.shift(1)

From 47feb3056a2d1447d46adcdb82732604d579a414 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 14:34:21 +0200
Subject: [PATCH 16/51] Update test_diff.py

---
 pandas/tests/series/test_diff.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 692b0c5ae9c1a..a15c72360aada 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -6,7 +6,7 @@
 
 
 class TestDiff(TestData):
-    def test_ts_diff(self):
+    def test_diff(self):
         # Just run the function
         self.ts.diff()
 
@@ -28,7 +28,6 @@ def test_ts_diff(self):
         xp = self.ts - self.ts
         assert_series_equal(rs, xp)
         
-    def test_datetime_diff(self):
         # datetime diff (GH3100)
         s = Series(date_range("20130102", periods=5))
         rs = s - s.shift(1)
@@ -49,7 +48,6 @@ def test_datetime_diff(self):
             result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
         )
         
-    def test_boolean_diff(self):
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()

From d425cdf273d13c53010a8b8ba6194b2d56d4c3b7 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 15:25:20 +0200
Subject: [PATCH 17/51] Adding nan test

---
 pandas/tests/series/test_diff.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index a15c72360aada..43d7a9d41cf77 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -51,4 +51,9 @@ def test_diff(self):
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()
-        assert_series_equal(result, Series[nan, True, False, True, False])
+        assert_series_equal(result, Series([nan, True, False, True, False]))
+        
+        # boolean nan series
+        s = Series([False, True, nan, False, False])
+        result = s.diff()
+        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype = "object"))

From 050b8cb424e31fd7118354b033f3c40759999a30 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 16:05:54 +0200
Subject: [PATCH 18/51] STYLE: Black formatting

---
 pandas/tests/series/test_diff.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 43d7a9d41cf77..7e303be7ee770 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -27,7 +27,7 @@ def test_diff(self):
         rs = self.ts.diff(0)
         xp = self.ts - self.ts
         assert_series_equal(rs, xp)
-        
+
         # datetime diff (GH3100)
         s = Series(date_range("20130102", periods=5))
         rs = s - s.shift(1)
@@ -47,13 +47,13 @@ def test_diff(self):
         assert_series_equal(
             result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
         )
-        
+
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()
         assert_series_equal(result, Series([nan, True, False, True, False]))
-        
+
         # boolean nan series
         s = Series([False, True, nan, False, False])
         result = s.diff()
-        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype = "object"))
+        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))

From e028aefa828dfa89a68fc90d3a16764826b36e32 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 6 Aug 2019 17:02:33 +0200
Subject: [PATCH 19/51] Import order changed

---
 pandas/tests/series/test_diff.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 7e303be7ee770..1d8c17dfa989b 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -1,7 +1,7 @@
 from numpy import nan
 from pandas import Series, date_range
-from pandas.tests.series.common import TestData
 from pandas.core.indexes.timedeltas import TimedeltaIndex
+from pandas.tests.series.common import TestData
 from pandas.util.testing import assert_series_equal
 
 

From 9d947dbd6f18a563e882a567dc6035382c8d30cf Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Wed, 7 Aug 2019 13:08:01 +0200
Subject: [PATCH 20/51] Update test_diff.py

---
 pandas/tests/series/test_diff.py | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 1d8c17dfa989b..6df0955b96c3d 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -51,9 +51,4 @@ def test_diff(self):
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()
-        assert_series_equal(result, Series([nan, True, False, True, False]))
-
-        # boolean nan series
-        s = Series([False, True, nan, False, False])
-        result = s.diff()
-        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))
+        assert_series_equal(result, Series[nan, True, False, True, False])

From b115c9ecf42675ea702bad823f8269e7f5fa763b Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Wed, 7 Aug 2019 13:13:27 +0200
Subject: [PATCH 21/51] Update test_diff.py

---
 pandas/tests/series/test_diff.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
index 6df0955b96c3d..1d8c17dfa989b 100644
--- a/pandas/tests/series/test_diff.py
+++ b/pandas/tests/series/test_diff.py
@@ -51,4 +51,9 @@ def test_diff(self):
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()
-        assert_series_equal(result, Series[nan, True, False, True, False])
+        assert_series_equal(result, Series([nan, True, False, True, False]))
+
+        # boolean nan series
+        s = Series([False, True, nan, False, False])
+        result = s.diff()
+        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))

From 865e91388624ebb1da3eab25e18a50f61782262f Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 20:33:06 +0200
Subject: [PATCH 22/51] Moving test_diff.py to test_analytics.py

As requested...
---
 pandas/tests/series/test_analytics.py | 56 +++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 3a5a387b919be..388f1768ffd0c 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -20,6 +20,7 @@
 from pandas.api.types import is_scalar
 from pandas.core.index import MultiIndex
 from pandas.core.indexes.datetimes import Timestamp
+from pandas.core.indexes.timedeltas import TimedeltaIndex
 import pandas.util.testing as tm
 from pandas.util.testing import (
     assert_almost_equal,
@@ -236,7 +237,62 @@ def test_npdiff(self):
 
         r = np.diff(s)
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
+        
+    def test_diff(self):
+        '''
+        Combined datetime ranges, normal diff and boolean diff test.
+        '''
+        # Just run the function
+        self.ts.diff()
+
+        # int dtype
+        a = 10000000000000000
+        b = a + 1
+        s = Series([a, b])
+
+        rs = s.diff()
+        assert rs[1] == 1
+
+        # neg n
+        rs = self.ts.diff(-1)
+        xp = self.ts - self.ts.shift(-1)
+        assert_series_equal(rs, xp)
+
+        # 0
+        rs = self.ts.diff(0)
+        xp = self.ts - self.ts
+        assert_series_equal(rs, xp)
+
+        # datetime diff (GH3100)
+        s = Series(date_range("20130102", periods=5))
+        rs = s - s.shift(1)
+        xp = s.diff()
+        assert_series_equal(rs, xp)
+
+        # timedelta diff
+        nrs = rs - rs.shift(1)
+        nxp = xp.diff()
+        assert_series_equal(nrs, nxp)
+
+        # with tz
+        s = Series(
+            date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
+        )
+        result = s.diff()
+        assert_series_equal(
+            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
+        )
+
+        # boolean series
+        s = Series([False, True, True, False, False])
+        result = s.diff()
+        assert_series_equal(result, Series([nan, True, False, True, False]))
 
+        # boolean nan series
+        s = Series([False, True, nan, False, False])
+        result = s.diff()
+        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))
+        
     def _check_accum_op(self, name, datetime_series_, check_dtype=True):
         func = getattr(np, name)
         tm.assert_numpy_array_equal(

From 6f8986b7fe4bd286c8f8116c3ba066762996da9a Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 20:34:58 +0200
Subject: [PATCH 23/51] Removed test_diff.py, added to test_analytics

---
 pandas/tests/series/test_diff.py | 59 --------------------------------
 1 file changed, 59 deletions(-)
 delete mode 100644 pandas/tests/series/test_diff.py

diff --git a/pandas/tests/series/test_diff.py b/pandas/tests/series/test_diff.py
deleted file mode 100644
index 1d8c17dfa989b..0000000000000
--- a/pandas/tests/series/test_diff.py
+++ /dev/null
@@ -1,59 +0,0 @@
-from numpy import nan
-from pandas import Series, date_range
-from pandas.core.indexes.timedeltas import TimedeltaIndex
-from pandas.tests.series.common import TestData
-from pandas.util.testing import assert_series_equal
-
-
-class TestDiff(TestData):
-    def test_diff(self):
-        # Just run the function
-        self.ts.diff()
-
-        # int dtype
-        a = 10000000000000000
-        b = a + 1
-        s = Series([a, b])
-
-        rs = s.diff()
-        assert rs[1] == 1
-
-        # neg n
-        rs = self.ts.diff(-1)
-        xp = self.ts - self.ts.shift(-1)
-        assert_series_equal(rs, xp)
-
-        # 0
-        rs = self.ts.diff(0)
-        xp = self.ts - self.ts
-        assert_series_equal(rs, xp)
-
-        # datetime diff (GH3100)
-        s = Series(date_range("20130102", periods=5))
-        rs = s - s.shift(1)
-        xp = s.diff()
-        assert_series_equal(rs, xp)
-
-        # timedelta diff
-        nrs = rs - rs.shift(1)
-        nxp = xp.diff()
-        assert_series_equal(nrs, nxp)
-
-        # with tz
-        s = Series(
-            date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
-        )
-        result = s.diff()
-        assert_series_equal(
-            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
-        )
-
-        # boolean series
-        s = Series([False, True, True, False, False])
-        result = s.diff()
-        assert_series_equal(result, Series([nan, True, False, True, False]))
-
-        # boolean nan series
-        s = Series([False, True, nan, False, False])
-        result = s.diff()
-        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))

From 081c2c8117b58dd2292d19110599b6045472cc82 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 20:43:13 +0200
Subject: [PATCH 24/51] Removing tailing whitespaces

---
 pandas/tests/series/test_analytics.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 388f1768ffd0c..30cf9c6fd2bd8 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -237,7 +237,7 @@ def test_npdiff(self):
 
         r = np.diff(s)
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
-        
+
     def test_diff(self):
         '''
         Combined datetime ranges, normal diff and boolean diff test.
@@ -292,7 +292,7 @@ def test_diff(self):
         s = Series([False, True, nan, False, False])
         result = s.diff()
         assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))
-        
+
     def _check_accum_op(self, name, datetime_series_, check_dtype=True):
         func = getattr(np, name)
         tm.assert_numpy_array_equal(

From 96bb1b420b779c7489a0e822429f97520ab325ad Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 22:13:57 +0200
Subject: [PATCH 25/51] STYLE: Black formatting

---
 pandas/tests/series/test_analytics.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 30cf9c6fd2bd8..1d827ced89a08 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -239,9 +239,9 @@ def test_npdiff(self):
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
 
     def test_diff(self):
-        '''
+        """
         Combined datetime ranges, normal diff and boolean diff test.
-        '''
+        """
         # Just run the function
         self.ts.diff()
 

From 91ebae51144f6d6b66fefd00d4d47bc42e3cee41 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 22:16:04 +0200
Subject: [PATCH 26/51] Update test_analytics.py

---
 pandas/tests/series/test_analytics.py | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 1d827ced89a08..81331eeccdb7e 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -239,9 +239,7 @@ def test_npdiff(self):
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
 
     def test_diff(self):
-        """
-        Combined datetime ranges, normal diff and boolean diff test.
-        """
+        # Combined datetime diff, normal diff and boolean diff test
         # Just run the function
         self.ts.diff()
 

From 74a474f58fd2f6a2677ee31f5e6eee0f6cfaad59 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 22:16:27 +0200
Subject: [PATCH 27/51] Update test_analytics.py

---
 pandas/tests/series/test_analytics.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 81331eeccdb7e..877b4baddf839 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -240,7 +240,6 @@ def test_npdiff(self):
 
     def test_diff(self):
         # Combined datetime diff, normal diff and boolean diff test
-        # Just run the function
         self.ts.diff()
 
         # int dtype

From 40df511e671b8ac2b7538ff1e1db4e59f91db21f Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sat, 10 Aug 2019 22:33:59 +0200
Subject: [PATCH 28/51] Removing self.ts from code

---
 pandas/tests/series/test_analytics.py | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 877b4baddf839..c07f6e903d353 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -240,7 +240,8 @@ def test_npdiff(self):
 
     def test_diff(self):
         # Combined datetime diff, normal diff and boolean diff test
-        self.ts.diff()
+        ts = pd.Series([1, 2])
+        ts.diff()
 
         # int dtype
         a = 10000000000000000
@@ -251,13 +252,13 @@ def test_diff(self):
         assert rs[1] == 1
 
         # neg n
-        rs = self.ts.diff(-1)
-        xp = self.ts - self.ts.shift(-1)
+        rs = ts.diff(-1)
+        xp = ts - ts.shift(-1)
         assert_series_equal(rs, xp)
 
         # 0
-        rs = self.ts.diff(0)
-        xp = self.ts - self.ts
+        rs = ts.diff(0)
+        xp = ts - ts
         assert_series_equal(rs, xp)
 
         # datetime diff (GH3100)

From 18a2e356f644515916f541f781bf3e55ca5876ee Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sun, 11 Aug 2019 00:09:07 +0200
Subject: [PATCH 29/51] Update test_analytics.py

---
 pandas/tests/series/test_analytics.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index c07f6e903d353..e916edc0bc799 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -238,9 +238,9 @@ def test_npdiff(self):
         r = np.diff(s)
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
 
-    def test_diff(self):
+    def test_dt_nm_bool_diff(self):
         # Combined datetime diff, normal diff and boolean diff test
-        ts = pd.Series([1, 2])
+        ts = Series([1, 2, 3])
         ts.diff()
 
         # int dtype

From 716a70e9fd94828e9c3f6ffb8802e83527dce173 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sun, 11 Aug 2019 00:53:38 +0200
Subject: [PATCH 30/51] Adding tm.makeTimeSeries, as in the original

---
 pandas/tests/series/test_analytics.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index e916edc0bc799..d60df28df06bb 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -240,7 +240,7 @@ def test_npdiff(self):
 
     def test_dt_nm_bool_diff(self):
         # Combined datetime diff, normal diff and boolean diff test
-        ts = Series([1, 2, 3])
+        ts = tm.makeTimeSeries(name='ts')
         ts.diff()
 
         # int dtype

From e879dd7fc384b5e58677e91c36c53389e23f937f Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sun, 11 Aug 2019 01:56:41 +0200
Subject: [PATCH 31/51] STYLE: Black

---
 pandas/tests/series/test_analytics.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index d60df28df06bb..d329097ddc666 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -240,7 +240,7 @@ def test_npdiff(self):
 
     def test_dt_nm_bool_diff(self):
         # Combined datetime diff, normal diff and boolean diff test
-        ts = tm.makeTimeSeries(name='ts')
+        ts = tm.makeTimeSeries(name="ts")
         ts.diff()
 
         # int dtype

From 850e315284d15bb51f12df3ba56755057b826c9c Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Mon, 2 Sep 2019 15:30:07 +0200
Subject: [PATCH 32/51] Adding updates

---
 pandas/core/arrays/datetimes.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/pandas/core/arrays/datetimes.py b/pandas/core/arrays/datetimes.py
index 70df708d36b3b..732f819e743a4 100644
--- a/pandas/core/arrays/datetimes.py
+++ b/pandas/core/arrays/datetimes.py
@@ -1063,6 +1063,7 @@ def tz_localize(self, tz, ambiguous="raise", nonexistent="raise", errors=None):
 
         Be careful with DST changes. When there is sequential data, pandas can
         infer the DST time:
+
         >>> s = pd.to_datetime(pd.Series(['2018-10-28 01:30:00',
         ...                               '2018-10-28 02:00:00',
         ...                               '2018-10-28 02:30:00',
@@ -1094,6 +1095,7 @@ def tz_localize(self, tz, ambiguous="raise", nonexistent="raise", errors=None):
         If the DST transition causes nonexistent times, you can shift these
         dates forward or backwards with a timedelta object or `'shift_forward'`
         or `'shift_backwards'`.
+
         >>> s = pd.to_datetime(pd.Series(['2015-03-29 02:30:00',
         ...                               '2015-03-29 03:30:00']))
         >>> s.dt.tz_localize('Europe/Warsaw', nonexistent='shift_forward')

From 8d2547a754e37295f96a2d0a1ccf899fc8f3d6a8 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Mon, 2 Sep 2019 15:46:41 +0200
Subject: [PATCH 33/51] BUG: Fix numpy boolean subtraction error in Series.diff
 (#27755)

---
 pandas/core/algorithms.py              |  4 ++
 pandas/tests/series/test_analytics.py  | 54 ++++++++++++++++++++++++++
 pandas/tests/series/test_timeseries.py | 42 --------------------
 3 files changed, 58 insertions(+), 42 deletions(-)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index c0ed198e200f1..1132f7d6ffdfd 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1915,6 +1915,7 @@ def diff(arr, n, axis=0):
     dtype = arr.dtype
 
     is_timedelta = False
+    is_bool = False
     if needs_i8_conversion(arr):
         dtype = np.float64
         arr = arr.view("i8")
@@ -1923,6 +1924,7 @@ def diff(arr, n, axis=0):
 
     elif is_bool_dtype(dtype):
         dtype = np.object_
+        is_bool = True
 
     elif is_integer_dtype(dtype):
         dtype = np.float64
@@ -1962,6 +1964,8 @@ def diff(arr, n, axis=0):
             result = res - lag
             result[mask] = na
             out_arr[res_indexer] = result
+        elif is_bool:
+            out_arr[res_indexer] = arr[res_indexer] ^ arr[lag_indexer]
         else:
             out_arr[res_indexer] = arr[res_indexer] - arr[lag_indexer]
 
diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 1ddaa4692d741..d6cb7f8d6a8be 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -20,6 +20,7 @@
 from pandas.api.types import is_scalar
 from pandas.core.index import MultiIndex
 from pandas.core.indexes.datetimes import Timestamp
+from pandas.core.indexes.timedeltas import TimedeltaIndex
 import pandas.util.testing as tm
 from pandas.util.testing import (
     assert_almost_equal,
@@ -237,6 +238,59 @@ def test_npdiff(self):
         r = np.diff(s)
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
 
+    def test_dt_nm_bool_diff(self):
+        # Combined datetime diff, normal diff and boolean diff test
+        ts = tm.makeTimeSeries(name="ts")
+        ts.diff()
+
+        # int dtype
+        a = 10000000000000000
+        b = a + 1
+        s = Series([a, b])
+
+        rs = s.diff()
+        assert rs[1] == 1
+
+        # neg n
+        rs = ts.diff(-1)
+        xp = ts - ts.shift(-1)
+        assert_series_equal(rs, xp)
+
+        # 0
+        rs = ts.diff(0)
+        xp = ts - ts
+        assert_series_equal(rs, xp)
+
+        # datetime diff (GH3100)
+        s = Series(date_range("20130102", periods=5))
+        rs = s - s.shift(1)
+        xp = s.diff()
+        assert_series_equal(rs, xp)
+
+        # timedelta diff
+        nrs = rs - rs.shift(1)
+        nxp = xp.diff()
+        assert_series_equal(nrs, nxp)
+
+        # with tz
+        s = Series(
+            date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
+        )
+        result = s.diff()
+        assert_series_equal(
+            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
+        )
+
+        # boolean series
+        s = Series([False, True, True, False, False])
+        result = s.diff()
+        assert_series_equal(result, Series([nan, True, False, True, False]))
+
+        # boolean nan series
+        s = Series([False, True, nan, False, False])
+        result = s.diff()
+        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))
+
     def _check_accum_op(self, name, datetime_series_, check_dtype=True):
         func = getattr(np, name)
         tm.assert_numpy_array_equal(
diff --git a/pandas/tests/series/test_timeseries.py b/pandas/tests/series/test_timeseries.py
index d0ca5d82c6b33..fbe3f929cf5b5 100644
--- a/pandas/tests/series/test_timeseries.py
+++ b/pandas/tests/series/test_timeseries.py
@@ -355,48 +355,6 @@ def test_asfreq_datetimeindex_empty_series(self):
         )
         tm.assert_index_equal(expected.index, result.index)
 
-    def test_diff(self):
-        # Just run the function
-        self.ts.diff()
-
-        # int dtype
-        a = 10000000000000000
-        b = a + 1
-        s = Series([a, b])
-
-        rs = s.diff()
-        assert rs[1] == 1
-
-        # neg n
-        rs = self.ts.diff(-1)
-        xp = self.ts - self.ts.shift(-1)
-        assert_series_equal(rs, xp)
-
-        # 0
-        rs = self.ts.diff(0)
-        xp = self.ts - self.ts
-        assert_series_equal(rs, xp)
-
-        # datetime diff (GH3100)
-        s = Series(date_range("20130102", periods=5))
-        rs = s - s.shift(1)
-        xp = s.diff()
-        assert_series_equal(rs, xp)
-
-        # timedelta diff
-        nrs = rs - rs.shift(1)
-        nxp = xp.diff()
-        assert_series_equal(nrs, nxp)
-
-        # with tz
-        s = Series(
-            date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
-        )
-        result = s.diff()
-        assert_series_equal(
-            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
-        )
-
     def test_pct_change(self):
         rs = self.ts.pct_change(fill_method=None)
         assert_series_equal(rs, self.ts / self.ts.shift(1) - 1)

From 3e0dbc74a39ad5ea197251a86d46dbe593b241d6 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 2 Sep 2019 16:27:10 +0200
Subject: [PATCH 34/51] Update v0.25.2.rst

Adding fix to Other
---
 doc/source/whatsnew/v0.25.2.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v0.25.2.rst b/doc/source/whatsnew/v0.25.2.rst
index 1cdf213d81a74..675469099735c 100644
--- a/doc/source/whatsnew/v0.25.2.rst
+++ b/doc/source/whatsnew/v0.25.2.rst
@@ -100,7 +100,7 @@ Other
 ^^^^^
 
 - Compatibility with Python 3.8 in :meth:`DataFrame.query` (:issue:`27261`)
--
+- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0 (:issue:`17294`)
 
 .. _whatsnew_0.252.contributors:
 

From f98cbf20aeb5fc932eb697feecf6ab8d873357f3 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 2 Sep 2019 16:48:30 +0200
Subject: [PATCH 35/51] Update v0.25.1.rst

---
 doc/source/whatsnew/v0.25.1.rst | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/doc/source/whatsnew/v0.25.1.rst b/doc/source/whatsnew/v0.25.1.rst
index f246a7f87c9b4..63dd56f4a3793 100644
--- a/doc/source/whatsnew/v0.25.1.rst
+++ b/doc/source/whatsnew/v0.25.1.rst
@@ -109,10 +109,7 @@ Other
 ^^^^^
 
 - Bug in :meth:`Series.replace` and :meth:`DataFrame.replace` when replacing timezone-aware timestamps using a dict-like replacer (:issue:`27720`)
-- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0 (:issue:`17294`)
--
--
->>>>>>> patch-1
+- Bug in :meth:`Series.rename` when using a custom type indexer. Now any value that isn't callable or dict-like is treated as a scalar. (:issue:`27814`)
 
 .. _whatsnew_0.251.contributors:
 

From 212765126539f52245b732170c8273c6dcf27524 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 09:01:18 +0200
Subject: [PATCH 36/51] Refactored code and added version number

---
 doc/source/whatsnew/v0.25.2.rst       |  2 +-
 doc/source/whatsnew/v1.0.0.rst        |  1 +
 pandas/tests/series/test_analytics.py | 40 +++++++++++++++------------
 3 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/doc/source/whatsnew/v0.25.2.rst b/doc/source/whatsnew/v0.25.2.rst
index 675469099735c..6cdec5a1c636d 100644
--- a/doc/source/whatsnew/v0.25.2.rst
+++ b/doc/source/whatsnew/v0.25.2.rst
@@ -100,7 +100,7 @@ Other
 ^^^^^
 
 - Compatibility with Python 3.8 in :meth:`DataFrame.query` (:issue:`27261`)
-- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0 (:issue:`17294`)
+- 
 
 .. _whatsnew_0.252.contributors:
 
diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index 3b6288146bdf2..5c27264c51761 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -211,6 +211,7 @@ Other
 - Trying to set the ``display.precision``, ``display.max_rows`` or ``display.max_columns`` using :meth:`set_option` to anything but a ``None`` or a positive int will raise a ``ValueError`` (:issue:`23348`)
 - Using :meth:`DataFrame.replace` with overlapping keys in a nested dictionary will no longer raise, now matching the behavior of a flat dictionary (:issue:`27660`)
 - :meth:`DataFrame.to_csv` and :meth:`Series.to_csv` now support dicts as ``compression`` argument with key ``'method'`` being the compression method and others as additional compression options when the compression method is ``'zip'``. (:issue:`26023`)
+- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0 (:issue:`17294`)
 
 
 .. _whatsnew_1000.contributors:
diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index d6cb7f8d6a8be..b2e8b08ce920a 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -238,7 +238,7 @@ def test_npdiff(self):
         r = np.diff(s)
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
 
-    def test_dt_nm_bool_diff(self):
+    def test_diff(self):
         # Combined datetime diff, normal diff and boolean diff test
         ts = tm.makeTimeSeries(name="ts")
         ts.diff()
@@ -248,48 +248,52 @@ def test_dt_nm_bool_diff(self):
         b = a + 1
         s = Series([a, b])
 
-        rs = s.diff()
-        assert rs[1] == 1
+        result = s.diff()
+        assert result[1] == 1
 
         # neg n
-        rs = ts.diff(-1)
-        xp = ts - ts.shift(-1)
-        assert_series_equal(rs, xp)
+        result = ts.diff(-1)
+        expected = ts - ts.shift(-1)
+        assert_series_equal(result, expected)
 
         # 0
-        rs = ts.diff(0)
-        xp = ts - ts
-        assert_series_equal(rs, xp)
+        result = ts.diff(0)
+        expected = ts - ts
+        assert_series_equal(result, expected)
 
         # datetime diff (GH3100)
         s = Series(date_range("20130102", periods=5))
-        rs = s - s.shift(1)
-        xp = s.diff()
-        assert_series_equal(rs, xp)
+        result = s - s.shift(1)
+        expected = s.diff()
+        assert_series_equal(result, expected)
 
         # timedelta diff
-        nrs = rs - rs.shift(1)
-        nxp = xp.diff()
-        assert_series_equal(nrs, nxp)
+        result = rs - rs.shift(1)
+        expected = xp.diff()
+        assert_series_equal(result, expected)
 
         # with tz
         s = Series(
             date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
         )
         result = s.diff()
+        expected = Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4)
         assert_series_equal(
-            result, Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
+            result, expected, name="foo")
         )
 
+        # tests added for fix #17294
         # boolean series
         s = Series([False, True, True, False, False])
         result = s.diff()
-        assert_series_equal(result, Series([nan, True, False, True, False]))
+        expected = Series([nan, True, False, True, False])
+        assert_series_equal(result, expected)
 
         # boolean nan series
         s = Series([False, True, nan, False, False])
         result = s.diff()
-        assert_series_equal(result, Series([nan, 1, nan, nan, 0], dtype="object"))
+        expected = Series([nan, 1, nan, nan, 0], dtype="object")
+        assert_series_equal(result, expected)
 
     def _check_accum_op(self, name, datetime_series_, check_dtype=True):
         func = getattr(np, name)

From b83135d21171de51f2e59206ea4fa2569cb31b37 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 09:24:41 +0200
Subject: [PATCH 37/51] Fixing typo

---
 pandas/tests/series/test_analytics.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index b2e8b08ce920a..cafaad0e14921 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -277,10 +277,8 @@ def test_diff(self):
             date_range("2000-01-01 09:00:00", periods=5, tz="US/Eastern"), name="foo"
         )
         result = s.diff()
-        expected = Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4)
-        assert_series_equal(
-            result, expected, name="foo")
-        )
+        expected = Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
+        assert_series_equal(result, expected)
 
         # tests added for fix #17294
         # boolean series

From b14f7c6b70356d3cfb43258a296858e40f750513 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 09:26:37 +0200
Subject: [PATCH 38/51] Moving comment

---
 pandas/tests/series/test_analytics.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index cafaad0e14921..37ed2a1b93595 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -280,8 +280,7 @@ def test_diff(self):
         expected = Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
         assert_series_equal(result, expected)
 
-        # tests added for fix #17294
-        # boolean series
+        # boolean series (test for fixing #17294)
         s = Series([False, True, True, False, False])
         result = s.diff()
         expected = Series([nan, True, False, True, False])

From d92d6c79466fd0c7149de17c39f5d55a4cdf5222 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 09:31:47 +0200
Subject: [PATCH 39/51] Removed a space

---
 doc/source/whatsnew/v0.25.2.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v0.25.2.rst b/doc/source/whatsnew/v0.25.2.rst
index 6cdec5a1c636d..1cdf213d81a74 100644
--- a/doc/source/whatsnew/v0.25.2.rst
+++ b/doc/source/whatsnew/v0.25.2.rst
@@ -100,7 +100,7 @@ Other
 ^^^^^
 
 - Compatibility with Python 3.8 in :meth:`DataFrame.query` (:issue:`27261`)
-- 
+-
 
 .. _whatsnew_0.252.contributors:
 

From b96bde8a5fc6132603081db9512ccc15c77f4180 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 13:34:36 +0200
Subject: [PATCH 40/51] Fixed typo

---
 pandas/tests/series/test_analytics.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 37ed2a1b93595..d22306d9682e1 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -268,8 +268,8 @@ def test_diff(self):
         assert_series_equal(result, expected)
 
         # timedelta diff
-        result = rs - rs.shift(1)
-        expected = xp.diff()
+        result = result - result.shift(1) # previous result
+        expected = expected.diff() # previously expected
         assert_series_equal(result, expected)
 
         # with tz

From 6a72f2c221297ddced5e4837c424b8185e0a4a99 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 14:14:05 +0200
Subject: [PATCH 41/51] Added spaces

---
 pandas/tests/series/test_analytics.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index d22306d9682e1..040e029eb98e9 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -268,8 +268,8 @@ def test_diff(self):
         assert_series_equal(result, expected)
 
         # timedelta diff
-        result = result - result.shift(1) # previous result
-        expected = expected.diff() # previously expected
+        result = result - result.shift(1)  # previous result
+        expected = expected.diff()  # previously expected
         assert_series_equal(result, expected)
 
         # with tz

From 030d305b69ea685ac53e380336830573d798ba9b Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 3 Sep 2019 14:25:36 +0200
Subject: [PATCH 42/51] Fixed typo

---
 doc/source/whatsnew/v1.0.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index 5c27264c51761..fb77a2ecdd112 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -211,7 +211,7 @@ Other
 - Trying to set the ``display.precision``, ``display.max_rows`` or ``display.max_columns`` using :meth:`set_option` to anything but a ``None`` or a positive int will raise a ``ValueError`` (:issue:`23348`)
 - Using :meth:`DataFrame.replace` with overlapping keys in a nested dictionary will no longer raise, now matching the behavior of a flat dictionary (:issue:`27660`)
 - :meth:`DataFrame.to_csv` and :meth:`Series.to_csv` now support dicts as ``compression`` argument with key ``'method'`` being the compression method and others as additional compression options when the compression method is ``'zip'``. (:issue:`26023`)
-- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 0.13.0 (:issue:`17294`)
+- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 1.13.0 (:issue:`17294`)
 
 
 .. _whatsnew_1000.contributors:

From 649042fce9bcf8ffc373ca0687289d573cd75acb Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Mon, 9 Sep 2019 18:03:40 +0200
Subject: [PATCH 43/51] Adding requirements

---
 pandas/core/algorithms.py | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index 1132f7d6ffdfd..596ae0ae636c2 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1916,6 +1916,7 @@ def diff(arr, n, axis=0):
 
     is_timedelta = False
     is_bool = False
+    is_obj_bool = False
     if needs_i8_conversion(arr):
         dtype = np.float64
         arr = arr.view("i8")
@@ -1929,6 +1930,10 @@ def diff(arr, n, axis=0):
     elif is_integer_dtype(dtype):
         dtype = np.float64
 
+    elif is_object_dtype(dtype):
+        if all(np.isin(arr, (True, False), False) == ~isna(arr)):
+            is_obj_bool = True
+
     dtype = np.dtype(dtype)
     out_arr = np.empty(arr.shape, dtype=dtype)
 
@@ -1969,6 +1974,13 @@ def diff(arr, n, axis=0):
         else:
             out_arr[res_indexer] = arr[res_indexer] - arr[lag_indexer]
 
+    if is_obj_bool:
+        # converting numbers to bool
+        na_index = isna(out_arr)
+        out_arr = out_arr.astype(bool).astype(object)
+        # resetting nan previously converted to True
+        out_arr[na_index] = np.nan
+
     if is_timedelta:
         out_arr = out_arr.astype("int64").view("timedelta64[ns]")
 

From d1c1755d39f0baf471d23cd75d3d57e2d655fdb5 Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Tue, 10 Sep 2019 13:53:54 +0200
Subject: [PATCH 44/51] Updating

---
 pandas/core/algorithms.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index 596ae0ae636c2..80ddf40068b9c 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1931,7 +1931,7 @@ def diff(arr, n, axis=0):
         dtype = np.float64
 
     elif is_object_dtype(dtype):
-        if all(np.isin(arr, (True, False), False) == ~isna(arr)):
+        if np.all(np.isin(arr, (True, False), False) | isna(arr)):
             is_obj_bool = True
 
     dtype = np.dtype(dtype)

From 1e4a7ae8b997b6727cd47bcbe4eef51677819d0f Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Wed, 11 Sep 2019 11:41:10 +0200
Subject: [PATCH 45/51] Updating documentation

---
 doc/source/whatsnew/v1.0.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index fb77a2ecdd112..c89363a82ba1a 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -211,7 +211,7 @@ Other
 - Trying to set the ``display.precision``, ``display.max_rows`` or ``display.max_columns`` using :meth:`set_option` to anything but a ``None`` or a positive int will raise a ``ValueError`` (:issue:`23348`)
 - Using :meth:`DataFrame.replace` with overlapping keys in a nested dictionary will no longer raise, now matching the behavior of a flat dictionary (:issue:`27660`)
 - :meth:`DataFrame.to_csv` and :meth:`Series.to_csv` now support dicts as ``compression`` argument with key ``'method'`` being the compression method and others as additional compression options when the compression method is ``'zip'``. (:issue:`26023`)
-- Bug in :meth:`Series.diff` where a boolean series would cause a TypeError (the - operator is deprecated) when using NumPy >= 1.13.0 (:issue:`17294`)
+- Bug in :meth:`Series.diff` where a boolean series would incorrectly raise a TypeError (the - operator is deprecated) (:issue:`17294`)
 
 
 .. _whatsnew_1000.contributors:

From d1c6b6577f3068d5fcfd96a7bc0a5b36434e687c Mon Sep 17 00:00:00 2001
From: Unprocessable <none>
Date: Thu, 12 Sep 2019 09:30:34 +0200
Subject: [PATCH 46/51] Adding object series test

---
 pandas/tests/series/test_analytics.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 040e029eb98e9..bd64df654f394 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -263,8 +263,8 @@ def test_diff(self):
 
         # datetime diff (GH3100)
         s = Series(date_range("20130102", periods=5))
-        result = s - s.shift(1)
-        expected = s.diff()
+        result = s.diff()
+        expected = s - s.shift(1)
         assert_series_equal(result, expected)
 
         # timedelta diff
@@ -286,10 +286,10 @@ def test_diff(self):
         expected = Series([nan, True, False, True, False])
         assert_series_equal(result, expected)
 
-        # boolean nan series
-        s = Series([False, True, nan, False, False])
+        # object series
+        s = Series([False, True, 5.0, nan, True, False])
         result = s.diff()
-        expected = Series([nan, 1, nan, nan, 0], dtype="object")
+        expected = s - s.shift(1)
         assert_series_equal(result, expected)
 
     def _check_accum_op(self, name, datetime_series_, check_dtype=True):

From bbd2550c5d6c31091c5fbcec14d144b0d2720010 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Sun, 15 Sep 2019 20:39:21 +0200
Subject: [PATCH 47/51] Removing the extra object NaN code

---
 pandas/core/algorithms.py | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/pandas/core/algorithms.py b/pandas/core/algorithms.py
index 80ddf40068b9c..1132f7d6ffdfd 100644
--- a/pandas/core/algorithms.py
+++ b/pandas/core/algorithms.py
@@ -1916,7 +1916,6 @@ def diff(arr, n, axis=0):
 
     is_timedelta = False
     is_bool = False
-    is_obj_bool = False
     if needs_i8_conversion(arr):
         dtype = np.float64
         arr = arr.view("i8")
@@ -1930,10 +1929,6 @@ def diff(arr, n, axis=0):
     elif is_integer_dtype(dtype):
         dtype = np.float64
 
-    elif is_object_dtype(dtype):
-        if np.all(np.isin(arr, (True, False), False) | isna(arr)):
-            is_obj_bool = True
-
     dtype = np.dtype(dtype)
     out_arr = np.empty(arr.shape, dtype=dtype)
 
@@ -1974,13 +1969,6 @@ def diff(arr, n, axis=0):
         else:
             out_arr[res_indexer] = arr[res_indexer] - arr[lag_indexer]
 
-    if is_obj_bool:
-        # converting numbers to bool
-        na_index = isna(out_arr)
-        out_arr = out_arr.astype(bool).astype(object)
-        # resetting nan previously converted to True
-        out_arr[na_index] = np.nan
-
     if is_timedelta:
         out_arr = out_arr.astype("int64").view("timedelta64[ns]")
 

From 21defe64549a0b76195818aa5420bf2c28b15168 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 23 Sep 2019 16:10:58 +0200
Subject: [PATCH 48/51] Adding requirements

Looks like I will be parametrizing and splitting the function into several functions. If there are no bugs, this should do.
---
 pandas/tests/series/test_analytics.py | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index bd64df654f394..6bfba0576d634 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -229,7 +229,7 @@ def test_cummax_timedelta64(self):
         result = s.cummax(skipna=False)
         tm.assert_series_equal(expected, result)
 
-    def test_npdiff(self):
+    def test_np_diff(self):
         pytest.skip("skipping due to Series no longer being an ndarray")
 
         # no longer works as the return type of np.diff is now nd.array
@@ -238,11 +238,7 @@ def test_npdiff(self):
         r = np.diff(s)
         assert_series_equal(Series([nan, 0, 0, 0, nan]), r)
 
-    def test_diff(self):
-        # Combined datetime diff, normal diff and boolean diff test
-        ts = tm.makeTimeSeries(name="ts")
-        ts.diff()
-
+    def test_int_diff(self):
         # int dtype
         a = 10000000000000000
         b = a + 1
@@ -251,6 +247,11 @@ def test_diff(self):
         result = s.diff()
         assert result[1] == 1
 
+    def test_tz_diff(self):
+        # Combined datetime diff, normal diff and boolean diff test
+        ts = tm.makeTimeSeries(name="ts")
+        ts.diff()
+
         # neg n
         result = ts.diff(-1)
         expected = ts - ts.shift(-1)
@@ -280,12 +281,17 @@ def test_diff(self):
         expected = Series(TimedeltaIndex(["NaT"] + ["1 days"] * 4), name="foo")
         assert_series_equal(result, expected)
 
+    @pytest.mark.parametrize(
+        "input,output,diff", [([False, True, True, False, False], [nan, True, False, True, False], 1)]
+    )
+    def test_bool_diff(self, input, output, diff):
         # boolean series (test for fixing #17294)
-        s = Series([False, True, True, False, False])
+        s = Series(input)
         result = s.diff()
-        expected = Series([nan, True, False, True, False])
+        expected = Series(output)
         assert_series_equal(result, expected)
 
+    def test_obj_diff(self):
         # object series
         s = Series([False, True, 5.0, nan, True, False])
         result = s.diff()

From 62275649302be16b33febc3e8f6014910adb80ab Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 23 Sep 2019 16:50:25 +0200
Subject: [PATCH 49/51] BLACK formatting

---
 pandas/tests/series/test_analytics.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 6bfba0576d634..8f19f3000df30 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -282,7 +282,8 @@ def test_tz_diff(self):
         assert_series_equal(result, expected)
 
     @pytest.mark.parametrize(
-        "input,output,diff", [([False, True, True, False, False], [nan, True, False, True, False], 1)]
+        "input,output,diff",
+        [([False, True, True, False, False], [nan, True, False, True, False], 1)]
     )
     def test_bool_diff(self, input, output, diff):
         # boolean series (test for fixing #17294)

From 88cea85f03d3d4a6f6e2425a1d3bd7904c719bb8 Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Tue, 24 Sep 2019 10:03:03 +0200
Subject: [PATCH 50/51] Adding comma

---
 pandas/tests/series/test_analytics.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/series/test_analytics.py b/pandas/tests/series/test_analytics.py
index 8f19f3000df30..08aa3ad02e0ed 100644
--- a/pandas/tests/series/test_analytics.py
+++ b/pandas/tests/series/test_analytics.py
@@ -283,7 +283,7 @@ def test_tz_diff(self):
 
     @pytest.mark.parametrize(
         "input,output,diff",
-        [([False, True, True, False, False], [nan, True, False, True, False], 1)]
+        [([False, True, True, False, False], [nan, True, False, True, False], 1)],
     )
     def test_bool_diff(self, input, output, diff):
         # boolean series (test for fixing #17294)

From acc8f87b734b4c6a09bdf14d3cf37dc1e558c93f Mon Sep 17 00:00:00 2001
From: Unprocessable <Unprocessable@users.noreply.github.com>
Date: Mon, 30 Sep 2019 13:22:16 +0200
Subject: [PATCH 51/51] Changing bug description

Changing the description again. The numpy version and 'the - operator is deprecated' are now both removed.
---
 doc/source/whatsnew/v1.0.0.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/source/whatsnew/v1.0.0.rst b/doc/source/whatsnew/v1.0.0.rst
index 9690621207e2d..37f559e45ec71 100644
--- a/doc/source/whatsnew/v1.0.0.rst
+++ b/doc/source/whatsnew/v1.0.0.rst
@@ -240,7 +240,7 @@ Other
 - Trying to set the ``display.precision``, ``display.max_rows`` or ``display.max_columns`` using :meth:`set_option` to anything but a ``None`` or a positive int will raise a ``ValueError`` (:issue:`23348`)
 - Using :meth:`DataFrame.replace` with overlapping keys in a nested dictionary will no longer raise, now matching the behavior of a flat dictionary (:issue:`27660`)
 - :meth:`DataFrame.to_csv` and :meth:`Series.to_csv` now support dicts as ``compression`` argument with key ``'method'`` being the compression method and others as additional compression options when the compression method is ``'zip'``. (:issue:`26023`)
-- Bug in :meth:`Series.diff` where a boolean series would incorrectly raise a TypeError (the - operator is deprecated) (:issue:`17294`)
+- Bug in :meth:`Series.diff` where a boolean series would incorrectly raise a ``TypeError`` (:issue:`17294`)
 - :meth:`Series.append` will no longer raise a ``TypeError`` when passed a tuple of ``Series`` (:issue:`28410`)
 
 .. _whatsnew_1000.contributors: