DEPR: deprecate Index.is_integer

doc/source/whatsnew/v2.0.0.rst

@@ -416,7 +416,7 @@ Other API changes
 
 Deprecations
 ~~~~~~~~~~~~
--
+- :meth:`Index.is_integer` has been deprecated. Use :func:`pandas.api.types.is_integer_dtype` instead (:issue:`50042`)
 
 .. ---------------------------------------------------------------------------
 

pandas/_testing/asserters.py

@@ -15,6 +15,7 @@
     is_bool,
     is_categorical_dtype,
     is_extension_array_dtype,
+    is_integer_dtype,
     is_interval_dtype,
     is_number,
     is_numeric_dtype,
@@ -1322,7 +1323,7 @@ def assert_indexing_slices_equivalent(ser: Series, l_slc: slice, i_slc: slice) -
 
     assert_series_equal(ser.loc[l_slc], expected)
 
-    if not ser.index.is_integer():
+    if not is_integer_dtype(ser.index):
         # For integer indices, .loc and plain getitem are position-based.
         assert_series_equal(ser[l_slc], expected)
 

pandas/core/indexes/base.py

@@ -98,6 +98,7 @@
     is_float_dtype,
     is_hashable,
     is_integer,
+    is_integer_dtype,
     is_interval_dtype,
     is_iterator,
     is_list_like,
@@ -2200,7 +2201,7 @@ def is_boolean(self) -> bool:
 
         See Also
         --------
-        is_integer : Check if the Index only consists of integers.
+        is_integer : Check if the Index only consists of integers (deprecated).
         is_floating : Check if the Index is a floating type.
         is_numeric : Check if the Index only consists of numeric data.
         is_object : Check if the Index is of the object dtype.
@@ -2228,6 +2229,9 @@ def is_integer(self) -> bool:
         """
         Check if the Index only consists of integers.
 
+        .. deprecated:: 2.0.0
+            Use `pandas.api.types.is_integer_dtype` instead.
+
         Returns
         -------
         bool
@@ -2256,6 +2260,12 @@ def is_integer(self) -> bool:
         >>> idx.is_integer()
         False
         """
+        warnings.warn(
+            f"{type(self).__name__}.is_integer is deprecated."
+            "Use pandas.api.types.is_integer_dtype instead",
+            FutureWarning,
+            stacklevel=find_stack_level(),
+        )
         return self.inferred_type in ["integer"]
 
     @final
@@ -2275,7 +2285,7 @@ def is_floating(self) -> bool:
         See Also
         --------
         is_boolean : Check if the Index only consists of booleans.
-        is_integer : Check if the Index only consists of integers.
+        is_integer : Check if the Index only consists of integers (deprecated).
         is_numeric : Check if the Index only consists of numeric data.
         is_object : Check if the Index is of the object dtype.
         is_categorical : Check if the Index holds categorical data.
@@ -2314,7 +2324,7 @@ def is_numeric(self) -> bool:
         See Also
         --------
         is_boolean : Check if the Index only consists of booleans.
-        is_integer : Check if the Index only consists of integers.
+        is_integer : Check if the Index only consists of integers (deprecated).
         is_floating : Check if the Index is a floating type.
         is_object : Check if the Index is of the object dtype.
         is_categorical : Check if the Index holds categorical data.
@@ -2357,7 +2367,7 @@ def is_object(self) -> bool:
         See Also
         --------
         is_boolean : Check if the Index only consists of booleans.
-        is_integer : Check if the Index only consists of integers.
+        is_integer : Check if the Index only consists of integers (deprecated).
         is_floating : Check if the Index is a floating type.
         is_numeric : Check if the Index only consists of numeric data.
         is_categorical : Check if the Index holds categorical data.
@@ -2398,7 +2408,7 @@ def is_categorical(self) -> bool:
         --------
         CategoricalIndex : Index for categorical data.
         is_boolean : Check if the Index only consists of booleans.
-        is_integer : Check if the Index only consists of integers.
+        is_integer : Check if the Index only consists of integers (deprecated).
         is_floating : Check if the Index is a floating type.
         is_numeric : Check if the Index only consists of numeric data.
         is_object : Check if the Index is of the object dtype.
@@ -2441,7 +2451,7 @@ def is_interval(self) -> bool:
         --------
         IntervalIndex : Index for Interval objects.
         is_boolean : Check if the Index only consists of booleans.
-        is_integer : Check if the Index only consists of integers.
+        is_integer : Check if the Index only consists of integers (deprecated).
         is_floating : Check if the Index is a floating type.
         is_numeric : Check if the Index only consists of numeric data.
         is_object : Check if the Index is of the object dtype.
@@ -3883,7 +3893,7 @@ def is_int(v):
 
         if kind == "getitem":
             # called from the getitem slicers, validate that we are in fact integers
-            if self.is_integer():
+            if is_integer_dtype(self.dtype):
                 if is_frame:
                     # unambiguously positional, no deprecation
                     pass
@@ -3919,7 +3929,7 @@ def is_int(v):
                         FutureWarning,
                         stacklevel=find_stack_level(),
                     )
-            if self.is_integer() or is_index_slice:
+            if is_integer_dtype(self.dtype) or is_index_slice:
                 # Note: these checks are redundant if we know is_index_slice
                 self._validate_indexer("slice", key.start, "getitem")
                 self._validate_indexer("slice", key.stop, "getitem")

pandas/tests/indexes/common.py

@@ -795,6 +795,12 @@ def test_inv(self, simple_index):
             with pytest.raises(TypeError, match=msg):
                 ~Series(idx)
 
+    def test_is_integer_is_deprecated(self, simple_index):
+        # GH50042
+        idx = simple_index
+        with tm.assert_produces_warning(FutureWarning):
+            idx.is_integer()
+
 
 class NumericBase(Base):
     """

pandas/tests/indexing/test_indexing.py

@@ -601,7 +601,7 @@ def test_index_type_coercion(self, indexer):
         # integer indexes
         for s in [Series(range(5)), Series(range(5), index=range(1, 6))]:
 
-            assert s.index.is_integer()
+            assert is_integer_dtype(s.index)
 
             s2 = s.copy()
             indexer(s2)[0.1] = 0