Remove cudf._lib.replace in favor of inlining pylibcudf

python/cudf/cudf/_lib/CMakeLists.txt

@@ -28,7 +28,6 @@ set(cython_sources
     orc.pyx
     parquet.pyx
     reduce.pyx
-    replace.pyx
     round.pyx
     scalar.pyx
     sort.pyx

python/cudf/cudf/_lib/__init__.py

@@ -16,7 +16,6 @@
     orc,
     parquet,
     reduce,
-    replace,
     round,
     sort,
     stream_compaction,

python/cudf/cudf/core/column/categorical.py

@@ -843,9 +843,9 @@ def values(self):
         """
         raise NotImplementedError("cudf.Categorical is not yet implemented")
 
-    def clip(self, lo: ScalarLike, hi: ScalarLike) -> "column.ColumnBase":
+    def clip(self, lo: ScalarLike, hi: ScalarLike) -> Self:
         return (
-            self.astype(self.categories.dtype).clip(lo, hi).astype(self.dtype)
+            self.astype(self.categories.dtype).clip(lo, hi).astype(self.dtype)  # type: ignore[return-value]
         )
 
     def data_array_view(
@@ -989,10 +989,8 @@ def find_and_replace(
         replacement_col = catmap._data["index"].astype(replaced.codes.dtype)
 
         replaced_codes = column.as_column(replaced.codes)
-        output = libcudf.replace.replace(
-            replaced_codes, to_replace_col, replacement_col
-        )
-        codes = as_unsigned_codes(len(new_cats["cats"]), output)
+        output = replaced_codes.replace(to_replace_col, replacement_col)
+        codes = as_unsigned_codes(len(new_cats["cats"]), output)  # type: ignore[arg-type]
 
         result = type(self)(
             data=self.data,  # type: ignore[arg-type]

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

@@ -241,8 +241,14 @@ def find_and_replace(
     ) -> Self:
         raise NotImplementedError
 
-    def clip(self, lo: ScalarLike, hi: ScalarLike) -> ColumnBase:
-        return libcudf.replace.clip(self, lo, hi)
+    @acquire_spill_lock()
+    def clip(self, lo: ScalarLike, hi: ScalarLike) -> Self:
+        plc_column = plc.replace.clamp(
+            self.to_pylibcudf(mode="read"),
+            cudf.Scalar(lo, self.dtype).device_value.c_value,
+            cudf.Scalar(hi, self.dtype).device_value.c_value,
+        )
+        return type(self).from_pylibcudf(plc_column)  # type: ignore[return-value]
 
     def equals(self, other: ColumnBase, check_dtypes: bool = False) -> bool:
         if self is other:
@@ -686,6 +692,18 @@ def _validate_fillna_value(
             return cudf.Scalar(fill_value, dtype=self.dtype)
         return as_column(fill_value)
 
+    @acquire_spill_lock()
+    def replace(
+        self, values_to_replace: Self, replacement_values: Self
+    ) -> Self:
+        return type(self).from_pylibcudf(  # type: ignore[return-value]
+            plc.replace.find_and_replace_all(
+                self.to_pylibcudf(mode="read"),
+                values_to_replace.to_pylibcudf(mode="read"),
+                replacement_values.to_pylibcudf(mode="read"),
+            )
+        )
+
     def fillna(
         self,
         fill_value: ScalarLike | ColumnLike,
@@ -704,11 +722,32 @@ def fillna(
                 return self.copy()
             else:
                 fill_value = self._validate_fillna_value(fill_value)
-        return libcudf.replace.replace_nulls(
-            input_col=self.nans_to_nulls(),
-            replacement=fill_value,
-            method=method,
-        )._with_type_metadata(self.dtype)
+
+        if fill_value is None and method is None:
+            raise ValueError("Must specify a fill 'value' or 'method'.")
+
+        if fill_value and method:
+            raise ValueError("Cannot specify both 'value' and 'method'.")
+
+        input_col = self.nans_to_nulls()
+
+        with acquire_spill_lock():
+            if method:
+                plc_replace = (
+                    plc.replace.ReplacePolicy.PRECEDING
+                    if method == "ffill"
+                    else plc.replace.ReplacePolicy.FOLLOWING
+                )
+            elif is_scalar(fill_value):
+                plc_replace = cudf.Scalar(fill_value).device_value.c_value
+            else:
+                plc_replace = fill_value.to_pylibcudf(mode="read")
+            plc_column = plc.replace.replace_nulls(
+                input_col.to_pylibcudf(mode="read"),
+                plc_replace,
+            )
+            result = type(self).from_pylibcudf(plc_column)
+        return result._with_type_metadata(self.dtype)  # type: ignore[return-value]
 
     def isnull(self) -> ColumnBase:
         """Identify missing values in a Column."""

python/cudf/cudf/core/column/numerical.py

@@ -482,7 +482,7 @@ def find_and_replace(
         to_replace: ColumnLike,
         replacement: ColumnLike,
         all_nan: bool = False,
-    ) -> NumericalColumn:
+    ) -> Self:
         """
         Return col with *to_replace* replaced with *value*.
         """
@@ -547,7 +547,7 @@ def find_and_replace(
             )
         elif len(replacement_col) == 1 and len(to_replace_col) == 0:
             return self.copy()
-        replaced = self.astype(common_type)
+        replaced = cast(Self, self.astype(common_type))
         df = cudf.DataFrame._from_data(
             {
                 "old": to_replace_col.astype(common_type),
@@ -563,9 +563,7 @@ def find_and_replace(
             )
             df = df.dropna(subset=["old"])
 
-        return libcudf.replace.replace(
-            replaced, df._data["old"], df._data["new"]
-        )
+        return replaced.replace(df._data["old"], df._data["new"])
 
     def _validate_fillna_value(
         self, fill_value: ScalarLike | ColumnLike

python/cudf/cudf/core/column/string.py

@@ -6038,7 +6038,7 @@ def find_and_replace(
             df = df.dropna(subset=["old"])
         else:
             res = self
-        return libcudf.replace.replace(res, df._data["old"], df._data["new"])
+        return res.replace(df._data["old"], df._data["new"])
 
     def normalize_binop_value(self, other) -> column.ColumnBase | cudf.Scalar:
         if (