Add proxy for inplace operations in cudf.pandas (#15695)

Fixes: #15676 

This PR implements `__iadd__` and `__isub__` methods to allow in-place subtraction and addition operations.

Forks out from #14534

Authors:
  - GALI PREM SAGAR (https://github.com/galipremsagar)

Approvers:
  - Bradley Dice (https://github.com/bdice)

URL: #15695

python/cudf/cudf/pandas/fast_slow_proxy.py

@@ -1083,9 +1083,23 @@ def _replace_closurevars(
     # Added on a per-proxy basis
     # https://github.com/rapidsai/xdf/pull/306#pullrequestreview-1636155428
     # "__hash__",
+    "__iadd__",
+    "__iand__",
+    "__iconcat__",
+    "__ifloordiv__",
+    "__ilshift__",
+    "__imatmul__",
+    "__imod__",
+    "__imul__",
     "__int__",
     "__invert__",
+    "__ior__",
+    "__ipow__",
+    "__irshift__",
+    "__isub__",
     "__iter__",
+    "__itruediv__",
+    "__ixor__",
     "__le__",
     "__len__",
     "__lshift__",

python/cudf/cudf_pandas_tests/test_cudf_pandas.py

@@ -1243,6 +1243,62 @@ def my_apply(df, unused):
     tm.assert_series_equal(result, expected)
 
 
+@pytest.mark.parametrize(
+    "op",
+    [
+        "__iadd__",
+        "__iand__",
+        "__ifloordiv__",
+        "__imod__",
+        "__imul__",
+        "__ior__",
+        "__ipow__",
+        "__isub__",
+        "__itruediv__",
+        "__ixor__",
+    ],
+)
+def test_inplace_ops(op):
+    xdf1 = xpd.DataFrame({"a": [10, 11, 12]})
+    xdf2 = xpd.DataFrame({"a": [1, 2, 3]})
+
+    df1 = pd.DataFrame({"a": [10, 11, 12]})
+    df2 = pd.DataFrame({"a": [1, 2, 3]})
+
+    actual = getattr(xdf1, op)(xdf2)
+    expected = getattr(df1, op)(df2)
+
+    tm.assert_equal(actual, expected)
+
+
+@pytest.mark.parametrize(
+    "op",
+    [
+        "__iadd__",
+        "__iand__",
+        "__ifloordiv__",
+        "__imod__",
+        "__imul__",
+        "__ior__",
+        "__ipow__",
+        "__isub__",
+        "__itruediv__",
+        "__ixor__",
+    ],
+)
+def test_inplace_ops_series(op):
+    xser1 = xpd.Series([10, 11, 12])
+    xser2 = xpd.Series([1, 2, 3])
+
+    ser1 = pd.Series([10, 11, 12])
+    ser2 = pd.Series([1, 2, 3])
+
+    actual = getattr(xser1, op)(xser2)
+    expected = getattr(ser1, op)(ser2)
+
+    tm.assert_equal(actual, expected)
+
+
 @pytest.mark.parametrize("data", [pd.NaT, 1234, "nat"])
 def test_timestamp(data):
     xtimestamp = xpd.Timestamp(data)