Move segmented_gather function from the copying module to the lists module

python/cudf/cudf/_lib/copying.pyx

@@ -4,7 +4,7 @@ import pickle
 
 from libc.stdint cimport uint8_t, uintptr_t
 from libcpp cimport bool
-from libcpp.memory cimport make_shared, shared_ptr, unique_ptr
+from libcpp.memory cimport unique_ptr
 from libcpp.utility cimport move
 from libcpp.vector cimport vector
 
@@ -30,10 +30,6 @@ from libcpp.memory cimport make_unique
 cimport pylibcudf.libcudf.contiguous_split as cpp_contiguous_split
 from pylibcudf.libcudf.column.column cimport column
 from pylibcudf.libcudf.column.column_view cimport column_view
-from pylibcudf.libcudf.lists.gather cimport (
-    segmented_gather as cpp_segmented_gather,
-)
-from pylibcudf.libcudf.lists.lists_column_view cimport lists_column_view
 from pylibcudf.libcudf.scalar.scalar cimport scalar
 from pylibcudf.libcudf.types cimport size_type
 
@@ -339,26 +335,6 @@ def get_element(Column input_column, size_type index):
     )
 
 
-@acquire_spill_lock()
-def segmented_gather(Column source_column, Column gather_map):
-    cdef shared_ptr[lists_column_view] source_LCV = (
-        make_shared[lists_column_view](source_column.view())
-    )
-    cdef shared_ptr[lists_column_view] gather_map_LCV = (
-        make_shared[lists_column_view](gather_map.view())
-    )
-    cdef unique_ptr[column] c_result
-
-    with nogil:
-        c_result = move(
-            cpp_segmented_gather(
-                source_LCV.get()[0], gather_map_LCV.get()[0])
-        )
-
-    result = Column.from_unique_ptr(move(c_result))
-    return result
-
-
 cdef class _CPackedColumns:
 
     @staticmethod

python/cudf/cudf/_lib/lists.pyx

@@ -9,24 +9,24 @@ from pylibcudf.libcudf.types cimport null_order, size_type
 from cudf._lib.column cimport Column
 from cudf._lib.utils cimport columns_from_pylibcudf_table
 
-import pylibcudf
+import pylibcudf as plc
 
 from pylibcudf cimport Scalar
 
 
 @acquire_spill_lock()
 def count_elements(Column col):
     return Column.from_pylibcudf(
-        pylibcudf.lists.count_elements(
+        plc.lists.count_elements(
             col.to_pylibcudf(mode="read"))
     )
 
 
 @acquire_spill_lock()
 def explode_outer(list source_columns, int explode_column_idx):
     return columns_from_pylibcudf_table(
-        pylibcudf.lists.explode_outer(
-            pylibcudf.Table([c.to_pylibcudf(mode="read") for c in source_columns]),
+        plc.lists.explode_outer(
+            plc.Table([c.to_pylibcudf(mode="read") for c in source_columns]),
             explode_column_idx,
         )
     )
@@ -35,7 +35,7 @@ def explode_outer(list source_columns, int explode_column_idx):
 @acquire_spill_lock()
 def distinct(Column col, bool nulls_equal, bool nans_all_equal):
     return Column.from_pylibcudf(
-        pylibcudf.lists.distinct(
+        plc.lists.distinct(
             col.to_pylibcudf(mode="read"),
             nulls_equal,
             nans_all_equal,
@@ -46,7 +46,7 @@ def distinct(Column col, bool nulls_equal, bool nans_all_equal):
 @acquire_spill_lock()
 def sort_lists(Column col, bool ascending, str na_position):
     return Column.from_pylibcudf(
-        pylibcudf.lists.sort_lists(
+        plc.lists.sort_lists(
             col.to_pylibcudf(mode="read"),
             ascending,
             null_order.BEFORE if na_position == "first" else null_order.AFTER,
@@ -58,7 +58,7 @@ def sort_lists(Column col, bool ascending, str na_position):
 @acquire_spill_lock()
 def extract_element_scalar(Column col, size_type index):
     return Column.from_pylibcudf(
-        pylibcudf.lists.extract_list_element(
+        plc.lists.extract_list_element(
             col.to_pylibcudf(mode="read"),
             index,
         )
@@ -68,7 +68,7 @@ def extract_element_scalar(Column col, size_type index):
 @acquire_spill_lock()
 def extract_element_column(Column col, Column index):
     return Column.from_pylibcudf(
-        pylibcudf.lists.extract_list_element(
+        plc.lists.extract_list_element(
             col.to_pylibcudf(mode="read"),
             index.to_pylibcudf(mode="read"),
         )
@@ -78,7 +78,7 @@ def extract_element_column(Column col, Column index):
 @acquire_spill_lock()
 def contains_scalar(Column col, py_search_key):
     return Column.from_pylibcudf(
-        pylibcudf.lists.contains(
+        plc.lists.contains(
             col.to_pylibcudf(mode="read"),
             <Scalar> py_search_key.device_value.c_value,
         )
@@ -88,7 +88,7 @@ def contains_scalar(Column col, py_search_key):
 @acquire_spill_lock()
 def index_of_scalar(Column col, object py_search_key):
     return Column.from_pylibcudf(
-        pylibcudf.lists.index_of(
+        plc.lists.index_of(
             col.to_pylibcudf(mode="read"),
             <Scalar> py_search_key.device_value.c_value,
             True,
@@ -99,7 +99,7 @@ def index_of_scalar(Column col, object py_search_key):
 @acquire_spill_lock()
 def index_of_column(Column col, Column search_keys):
     return Column.from_pylibcudf(
-        pylibcudf.lists.index_of(
+        plc.lists.index_of(
             col.to_pylibcudf(mode="read"),
             search_keys.to_pylibcudf(mode="read"),
             True,
@@ -110,8 +110,8 @@ def index_of_column(Column col, Column search_keys):
 @acquire_spill_lock()
 def concatenate_rows(list source_columns):
     return Column.from_pylibcudf(
-        pylibcudf.lists.concatenate_rows(
-            pylibcudf.Table([
+        plc.lists.concatenate_rows(
+            plc.Table([
                 c.to_pylibcudf(mode="read") for c in source_columns
             ])
         )
@@ -121,8 +121,18 @@ def concatenate_rows(list source_columns):
 @acquire_spill_lock()
 def concatenate_list_elements(Column input_column, dropna=False):
     return Column.from_pylibcudf(
-        pylibcudf.lists.concatenate_list_elements(
+        plc.lists.concatenate_list_elements(
             input_column.to_pylibcudf(mode="read"),
             dropna,
         )
     )
+
+
+@acquire_spill_lock()
+def segmented_gather(Column source_column, Column gather_map):
+    return Column.from_pylibcudf(
+        plc.lists.segmented_gather(
+            source_column.to_pylibcudf(mode="read"),
+            gather_map.to_pylibcudf(mode="read"),
+        )
+    )

python/cudf/cudf/core/column/lists.py

@@ -11,7 +11,6 @@
 from typing_extensions import Self
 
 import cudf
-from cudf._lib.copying import segmented_gather
 from cudf._lib.lists import (
     concatenate_list_elements,
     concatenate_rows,
@@ -22,6 +21,7 @@
     extract_element_scalar,
     index_of_column,
     index_of_scalar,
+    segmented_gather,
     sort_lists,
 )
 from cudf._lib.strings.convert.convert_lists import format_list_column