Use instance over is_foo_dtype

python/cudf/cudf/_lib/column.pyx

@@ -5,13 +5,13 @@ from typing import Literal
 
 import cupy as cp
 import numpy as np
+import pandas as pd
 
 import rmm
 
 import cudf
 import cudf._lib as libcudf
 from cudf._lib import pylibcudf
-from cudf.api.types import is_categorical_dtype, is_datetime64tz_dtype
 from cudf.core.buffer import (
     Buffer,
     ExposureTrackedBuffer,
@@ -344,10 +344,10 @@ cdef class Column:
             )
 
     cdef mutable_column_view mutable_view(self) except *:
-        if is_categorical_dtype(self.dtype):
+        if isinstance(self.dtype, cudf.CategoricalDtype):
             col = self.base_children[0]
             data_dtype = col.dtype
-        elif is_datetime64tz_dtype(self.dtype):
+        elif isinstance(self.dtype, pd.DatetimeTZDtype):
             col = self
             data_dtype = _get_base_dtype(col.dtype)
         else:
@@ -407,10 +407,10 @@ cdef class Column:
         return self._view(c_null_count)
 
     cdef column_view _view(self, libcudf_types.size_type null_count) except *:
-        if is_categorical_dtype(self.dtype):
+        if isinstance(self.dtype, cudf.CategoricalDtype):
             col = self.base_children[0]
             data_dtype = col.dtype
-        elif is_datetime64tz_dtype(self.dtype):
+        elif isinstance(self.dtype, pd.DatetimeTZDtype):
             col = self
             data_dtype = _get_base_dtype(col.dtype)
         else:
@@ -482,7 +482,7 @@ cdef class Column:
         # categoricals because cudf supports ordered and unordered categoricals
         # while libcudf supports only unordered categoricals (see
         # https://github.com/rapidsai/cudf/pull/8567).
-        if is_categorical_dtype(self.dtype):
+        if isinstance(self.dtype, cudf.CategoricalDtype):
             col = self.base_children[0]
         else:
             col = self
@@ -648,7 +648,7 @@ cdef class Column:
         """
         column_owner = isinstance(owner, Column)
         mask_owner = owner
-        if column_owner and is_categorical_dtype(owner.dtype):
+        if column_owner and isinstance(owner.dtype, cudf.CategoricalDtype):
             owner = owner.base_children[0]
 
         size = cv.size()

python/cudf/cudf/_lib/groupby.pyx

@@ -1,16 +1,17 @@
 # Copyright (c) 2020-2024, NVIDIA CORPORATION.
+from functools import singledispatch
 
 from pandas.core.groupby.groupby import DataError
 
-from cudf.api.types import (
-    is_categorical_dtype,
-    is_decimal_dtype,
-    is_interval_dtype,
-    is_list_dtype,
-    is_string_dtype,
-    is_struct_dtype,
-)
+from cudf.api.types import is_string_dtype
 from cudf.core.buffer import acquire_spill_lock
+from cudf.core.dtypes import (
+    CategoricalDtype,
+    DecimalDtype,
+    IntervalDtype,
+    ListDtype,
+    StructDtype,
+)
 
 from libcpp cimport bool
 from libcpp.memory cimport unique_ptr
@@ -73,6 +74,43 @@ _DECIMAL_AGGS = {
 ctypedef const scalar constscalar
 
 
+@singledispatch
+def get_valid_aggregation(dtype):
+    if is_string_dtype(dtype):
+        return _STRING_AGGS
+    return "ALL"
+
+
+@get_valid_aggregation.register
+def _(dtype: ListDtype):
+    return _LIST_AGGS
+
+
+@get_valid_aggregation.register
+def _(dtype: CategoricalDtype):
+    return _CATEGORICAL_AGGS
+
+
+@get_valid_aggregation.register
+def _(dtype: ListDtype):
+    return _LIST_AGGS
+
+
+@get_valid_aggregation.register
+def _(dtype: StructDtype):
+    return _STRUCT_AGGS
+
+
+@get_valid_aggregation.register
+def _(dtype: IntervalDtype):
+    return _INTERVAL_AGGS
+
+
+@get_valid_aggregation.register
+def _(dtype: DecimalDtype):
+    return _DECIMAL_AGGS
+
+
 cdef _agg_result_from_columns(
     vector[libcudf_groupby.aggregation_result]& c_result_columns,
     set column_included,
@@ -187,15 +225,7 @@ cdef class GroupBy:
         for i, (col, aggs) in enumerate(zip(values, aggregations)):
             dtype = col.dtype
 
-            valid_aggregations = (
-                _LIST_AGGS if is_list_dtype(dtype)
-                else _STRING_AGGS if is_string_dtype(dtype)
-                else _CATEGORICAL_AGGS if is_categorical_dtype(dtype)
-                else _STRUCT_AGGS if is_struct_dtype(dtype)
-                else _INTERVAL_AGGS if is_interval_dtype(dtype)
-                else _DECIMAL_AGGS if is_decimal_dtype(dtype)
-                else "ALL"
-            )
+            valid_aggregations = get_valid_aggregation(dtype)
             included_aggregations_i = []
 
             c_agg_request = move(libcudf_groupby.aggregation_request())
@@ -258,15 +288,7 @@ cdef class GroupBy:
         for i, (col, aggs) in enumerate(zip(values, aggregations)):
             dtype = col.dtype
 
-            valid_aggregations = (
-                _LIST_AGGS if is_list_dtype(dtype)
-                else _STRING_AGGS if is_string_dtype(dtype)
-                else _CATEGORICAL_AGGS if is_categorical_dtype(dtype)
-                else _STRUCT_AGGS if is_struct_dtype(dtype)
-                else _INTERVAL_AGGS if is_interval_dtype(dtype)
-                else _DECIMAL_AGGS if is_decimal_dtype(dtype)
-                else "ALL"
-            )
+            valid_aggregations = get_valid_aggregation(dtype)
             included_aggregations_i = []
 
             c_agg_request = move(libcudf_groupby.scan_request())

python/cudf/cudf/_lib/interop.pyx

@@ -1,4 +1,4 @@
-# Copyright (c) 2020-2023, NVIDIA CORPORATION.
+# Copyright (c) 2020-2024, NVIDIA CORPORATION.
 
 from cpython cimport pycapsule
 from libcpp.memory cimport shared_ptr, unique_ptr
@@ -18,8 +18,8 @@ from cudf._lib.cpp.table.table cimport table
 from cudf._lib.cpp.table.table_view cimport table_view
 from cudf._lib.utils cimport columns_from_unique_ptr, table_view_from_columns
 
-from cudf.api.types import is_list_dtype, is_struct_dtype
 from cudf.core.buffer import acquire_spill_lock
+from cudf.core.dtypes import ListDtype, StructDtype
 
 
 def from_dlpack(dlpack_capsule):
@@ -98,7 +98,7 @@ cdef vector[column_metadata] gather_metadata(object cols_dtypes) except *:
     if cols_dtypes is not None:
         for idx, (col_name, col_dtype) in enumerate(cols_dtypes):
             cpp_metadata.push_back(column_metadata(col_name.encode()))
-            if is_struct_dtype(col_dtype) or is_list_dtype(col_dtype):
+            if isinstance(col_dtype, (ListDtype, StructDtype)):
                 _set_col_children_metadata(col_dtype, cpp_metadata[idx])
     else:
         raise TypeError(
@@ -113,14 +113,14 @@ cdef _set_col_children_metadata(dtype,
 
     cdef column_metadata element_metadata
 
-    if is_struct_dtype(dtype):
+    if isinstance(dtype, StructDtype):
         for name, value in dtype.fields.items():
             element_metadata = column_metadata(name.encode())
             _set_col_children_metadata(
                 value, element_metadata
             )
             col_meta.children_meta.push_back(element_metadata)
-    elif is_list_dtype(dtype):
+    elif isinstance(dtype, ListDtype):
         col_meta.children_meta.reserve(2)
         # Offsets - child 0
         col_meta.children_meta.push_back(column_metadata())

python/cudf/cudf/_lib/io/utils.pyx

@@ -1,4 +1,4 @@
-# Copyright (c) 2020-2023, NVIDIA CORPORATION.
+# Copyright (c) 2020-2024, NVIDIA CORPORATION.
 
 from cpython.buffer cimport PyBUF_READ
 from cpython.memoryview cimport PyMemoryView_FromMemory
@@ -23,7 +23,7 @@ import errno
 import io
 import os
 
-from cudf.api.types import is_struct_dtype
+from cudf.core.dtypes import StructDtype
 
 
 # Converts the Python source input to libcudf IO source_info
@@ -172,7 +172,7 @@ cdef Column update_column_struct_field_names(
             )
         col.set_base_children(tuple(children))
 
-    if is_struct_dtype(col):
+    if isinstance(col.dtype, StructDtype):
         field_names.reserve(len(col.base_children))
         for i in range(info.children.size()):
             field_names.push_back(info.children[i].name)

python/cudf/cudf/_lib/json.pyx

@@ -1,4 +1,4 @@
-# Copyright (c) 2019-2023, NVIDIA CORPORATION.
+# Copyright (c) 2019-2024, NVIDIA CORPORATION.
 
 # cython: boundscheck = False
 
@@ -17,6 +17,7 @@ from libcpp.utility cimport move
 from libcpp.vector cimport vector
 
 cimport cudf._lib.cpp.io.types as cudf_io_types
+from cudf._lib.column cimport Column
 from cudf._lib.cpp.io.data_sink cimport data_sink
 from cudf._lib.cpp.io.json cimport (
     json_reader_options,
@@ -42,10 +43,6 @@ from cudf._lib.io.utils cimport (
 from cudf._lib.types cimport dtype_to_data_type
 from cudf._lib.utils cimport data_from_unique_ptr, table_view_from_table
 
-from cudf.api.types import is_list_dtype, is_struct_dtype
-
-from cudf._lib.column cimport Column
-
 
 cpdef read_json(object filepaths_or_buffers,
                 object dtype,
@@ -214,13 +211,12 @@ def write_json(
 cdef schema_element _get_cudf_schema_element_from_dtype(object dtype) except *:
     cdef schema_element s_element
     cdef data_type lib_type
-    if cudf.api.types.is_categorical_dtype(dtype):
+    dtype = cudf.dtype(dtype)
+    if isinstance(dtype, cudf.CategoricalDtype):
         raise NotImplementedError(
             "CategoricalDtype as dtype is not yet "
             "supported in JSON reader"
         )
-
-    dtype = cudf.dtype(dtype)
     lib_type = dtype_to_data_type(dtype)
     s_element.type = lib_type
     if isinstance(dtype, cudf.StructDtype):
@@ -237,19 +233,18 @@ cdef schema_element _get_cudf_schema_element_from_dtype(object dtype) except *:
 
 
 cdef data_type _get_cudf_data_type_from_dtype(object dtype) except *:
-    if cudf.api.types.is_categorical_dtype(dtype):
+    dtype = cudf.dtype(dtype)
+    if isinstance(dtype, cudf.CategoricalDtype):
         raise NotImplementedError(
             "CategoricalDtype as dtype is not yet "
             "supported in JSON reader"
         )
-
-    dtype = cudf.dtype(dtype)
     return dtype_to_data_type(dtype)
 
 cdef _set_col_children_metadata(Column col,
                                 column_name_info& col_meta):
     cdef column_name_info child_info
-    if is_struct_dtype(col):
+    if isinstance(col.dtype, cudf.StructDtype):
         for i, (child_col, name) in enumerate(
             zip(col.children, list(col.dtype.fields))
         ):
@@ -258,7 +253,7 @@ cdef _set_col_children_metadata(Column col,
             _set_col_children_metadata(
                 child_col, col_meta.children[i]
             )
-    elif is_list_dtype(col):
+    elif isinstance(col.dtype, cudf.ListDtype):
         for i, child_col in enumerate(col.children):
             col_meta.children.push_back(child_info)
             _set_col_children_metadata(

python/cudf/cudf/_lib/orc.pyx

@@ -1,4 +1,4 @@
-# Copyright (c) 2020-2023, NVIDIA CORPORATION.
+# Copyright (c) 2020-2024, NVIDIA CORPORATION.
 
 import cudf
 from cudf.core.buffer import acquire_spill_lock
@@ -59,7 +59,6 @@ from cudf._lib.utils cimport data_from_unique_ptr, table_view_from_table
 from pyarrow.lib import NativeFile
 
 from cudf._lib.utils import _index_level_name, generate_pandas_metadata
-from cudf.api.types import is_list_dtype, is_struct_dtype
 
 
 cpdef read_raw_orc_statistics(filepath_or_buffer):
@@ -474,15 +473,15 @@ cdef class ORCWriter:
 cdef _set_col_children_metadata(Column col,
                                 column_in_metadata& col_meta,
                                 list_column_as_map=False):
-    if is_struct_dtype(col):
+    if isinstance(col.dtype, cudf.StructDtype):
         for i, (child_col, name) in enumerate(
             zip(col.children, list(col.dtype.fields))
         ):
             col_meta.child(i).set_name(name.encode())
             _set_col_children_metadata(
                 child_col, col_meta.child(i), list_column_as_map
             )
-    elif is_list_dtype(col):
+    elif isinstance(col.dtype, cudf.ListDtype):
         if list_column_as_map:
             col_meta.set_list_column_as_map()
         _set_col_children_metadata(

python/cudf/cudf/_lib/parquet.pyx

@@ -1,4 +1,4 @@
-# Copyright (c) 2019-2023, NVIDIA CORPORATION.
+# Copyright (c) 2019-2024, NVIDIA CORPORATION.
 
 # cython: boundscheck = False
 
@@ -18,12 +18,7 @@ import numpy as np
 
 from cython.operator cimport dereference
 
-from cudf.api.types import (
-    is_decimal_dtype,
-    is_list_dtype,
-    is_list_like,
-    is_struct_dtype,
-)
+from cudf.api.types import is_list_like
 
 from cudf._lib.utils cimport data_from_unique_ptr
 
@@ -220,7 +215,7 @@ cpdef read_parquet(filepaths_or_buffers, columns=None, row_groups=None,
 
         # update the decimal precision of each column
         for col in names:
-            if is_decimal_dtype(df._data[col].dtype):
+            if isinstance(df._data[col].dtype, cudf.core.dtypes.DecimalDtype):
                 df._data[col].dtype.precision = (
                     meta_data_per_column[col]["metadata"]["precision"]
                 )
@@ -703,7 +698,7 @@ cdef _set_col_metadata(
         # is true.
         col_meta.set_nullability(True)
 
-    if is_struct_dtype(col):
+    if isinstance(col.dtype, cudf.StructDtype):
         for i, (child_col, name) in enumerate(
             zip(col.children, list(col.dtype.fields))
         ):
@@ -713,13 +708,11 @@ cdef _set_col_metadata(
                 col_meta.child(i),
                 force_nullable_schema
             )
-    elif is_list_dtype(col):
+    elif isinstance(col.dtype, cudf.ListDtype):
         _set_col_metadata(
             col.children[1],
             col_meta.child(1),
             force_nullable_schema
         )
-    else:
-        if is_decimal_dtype(col):
-            col_meta.set_decimal_precision(col.dtype.precision)
-        return
+    elif isinstance(col.dtype, cudf.core.dtypes.DecimalDtype):
+        col_meta.set_decimal_precision(col.dtype.precision)