test: cudf fixup, address pandas deprecationwarning (#2496)

Author: MarcoGorelli

narwhals/_dask/expr_dt.py

@@ -3,6 +3,7 @@
 from typing import TYPE_CHECKING
 
 from narwhals._duration import parse_interval_string
+from narwhals._pandas_like.utils import UNIT_DICT
 from narwhals._pandas_like.utils import calculate_timestamp_date
 from narwhals._pandas_like.utils import calculate_timestamp_datetime
 from narwhals._pandas_like.utils import native_to_narwhals_dtype
@@ -160,13 +161,11 @@ def total_nanoseconds(self) -> DaskExpr:
         )
 
     def truncate(self, every: str) -> DaskExpr:
-        _, unit = parse_interval_string(every)
+        multiple, unit = parse_interval_string(every)
         if unit in {"mo", "q", "y"}:
             msg = f"Truncating to {unit} is not supported yet for dask."
             raise NotImplementedError(msg)
-        if unit == "m":
-            every = every.replace("m", "min", 1)
+        freq = f"{multiple}{UNIT_DICT.get(unit, unit)}"
         return self._compliant_expr._with_callable(
-            lambda _input: _input.dt.floor(every),
-            "truncate",
+            lambda _input: _input.dt.floor(freq), "truncate"
         )

narwhals/_pandas_like/series_dt.py

@@ -5,6 +5,7 @@
 
 from narwhals._compliant.any_namespace import DateTimeNamespace
 from narwhals._duration import parse_interval_string
+from narwhals._pandas_like.utils import UNIT_DICT
 from narwhals._pandas_like.utils import PandasLikeSeriesNamespace
 from narwhals._pandas_like.utils import calculate_timestamp_date
 from narwhals._pandas_like.utils import calculate_timestamp_datetime
@@ -196,6 +197,11 @@ def timestamp(self, time_unit: TimeUnit) -> PandasLikeSeries:
     def truncate(self, every: str) -> PandasLikeSeries:
         multiple, unit = parse_interval_string(every)
         native = self.native
+        if self.implementation.is_cudf():
+            if multiple != 1:
+                msg = f"Only multiple `1` is supported for cuDF, got: {multiple}."
+                raise NotImplementedError(msg)
+            return self.with_native(self.native.dt.floor(UNIT_DICT.get(unit, unit)))
         dtype_backend = get_dtype_backend(native.dtype, self.compliant._implementation)
         if unit in {"mo", "q", "y"}:
             if self.implementation.is_cudf():
@@ -225,6 +231,6 @@ def truncate(self, every: str) -> PandasLikeSeries:
                 result_arr, dtype=native.dtype, index=native.index, name=native.name
             )
             return self.with_native(result_native)
-        if unit == "m":
-            every = every.replace("m", "min", 1)
-        return self.with_native(self.native.dt.floor(every))
+        return self.with_native(
+            self.native.dt.floor(f"{multiple}{UNIT_DICT.get(unit, unit)}")
+        )

narwhals/_pandas_like/utils.py

@@ -90,6 +90,8 @@
 $"""
 PATTERN_PA_DURATION = re.compile(PA_DURATION_RGX, re.VERBOSE)
 
+UNIT_DICT = {"d": "D", "m": "min"}
+
 
 def align_and_extract_native(
     lhs: PandasLikeSeries, rhs: PandasLikeSeries | object

tests/expr_and_series/dt/truncate_test.py

@@ -195,8 +195,11 @@ def test_truncate_custom(
         )
     if every.endswith("ns") and any(x in str(constructor) for x in ("polars", "duckdb")):
         request.applymarker(pytest.mark.xfail())
+    if "cudf" in str(constructor):
+        # https://github.com/rapidsai/cudf/issues/18654
+        request.applymarker(pytest.mark.xfail(reason="Not implemented"))
     if any(every.endswith(x) for x in ("mo", "q", "y")) and any(
-        x in str(constructor) for x in ("dask", "cudf")
+        x in str(constructor) for x in ("dask",)
     ):
         request.applymarker(pytest.mark.xfail(reason="Not implemented"))
     df = nw.from_native(constructor(data))

tests/expr_and_series/str/to_uppercase_to_lowercase_test.py

@@ -35,7 +35,7 @@ def test_str_to_uppercase(
     if (
         any(
             x in str(constructor)
-            for x in ("pandas_constructor", "pandas_nullable", "polars")
+            for x in ("pandas_constructor", "pandas_nullable", "polars", "cudf")
         )
         and "ẞ" in expected["a"][0]
     ):
@@ -72,7 +72,7 @@ def test_str_to_uppercase_series(
     if (
         any(
             x in str(constructor_eager)
-            for x in ("pandas_constructor", "pandas_nullable", "polars")
+            for x in ("pandas_constructor", "pandas_nullable", "polars", "cudf")
         )
         and "ẞ" in expected["a"][0]
     ):