test: use constructor_eager for testing gather_every (#2334)

* test: use constructor_eager for testing gather_every

* use constructor_eager in from_numpy tests

* coverage

Author: MarcoGorelli

tests/conftest.py

@@ -270,10 +270,4 @@ def pytest_generate_tests(metafunc: pytest.Metafunc) -> None:
             "constructor_eager", eager_constructors, ids=eager_constructors_ids
         )
     elif "constructor" in metafunc.fixturenames:
-        if (
-            any(x in str(metafunc.module) for x in ("from_dict", "from_numpy"))
-            and LAZY_CONSTRUCTORS["duckdb"] in constructors
-        ):
-            constructors.remove(LAZY_CONSTRUCTORS["duckdb"])
-            constructors_ids.remove("duckdb")
         metafunc.parametrize("constructor", constructors, ids=constructors_ids)

tests/frame/gather_every_test.py

@@ -1,39 +1,39 @@
 from __future__ import annotations
 
-from contextlib import nullcontext
-
+import pandas as pd
 import pytest
 
 import narwhals as nw_main
 import narwhals.stable.v1 as nw
-from tests.utils import Constructor
+from tests.utils import ConstructorEager
 from tests.utils import assert_equal_data
 
 data = {"a": list(range(10))}
 
 
 @pytest.mark.parametrize("n", [1, 2, 3])
 @pytest.mark.parametrize("offset", [1, 2, 3])
-def test_gather_every(
-    constructor: Constructor, n: int, offset: int, request: pytest.FixtureRequest
-) -> None:
-    if "pyspark" in str(constructor) or "duckdb" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
-    df_v1 = nw.from_native(constructor(data))
+def test_gather_every(constructor_eager: ConstructorEager, n: int, offset: int) -> None:
+    df_v1 = nw.from_native(constructor_eager(data))
     result = df_v1.gather_every(n=n, offset=offset)
     expected = {"a": data["a"][offset::n]}
     assert_equal_data(result, expected)
 
     # Test deprecation for LazyFrame in main namespace
-    df_main = nw_main.from_native(constructor(data))
-
-    context = (
-        pytest.deprecated_call(
-            match="is deprecated and will be removed in a future version"
-        )
-        if isinstance(df_main, nw_main.LazyFrame)
-        else nullcontext()
-    )
-
-    with context:
-        df_main.gather_every(n=n, offset=offset)
+    lf = nw_main.from_native(constructor_eager(data)).lazy()
+    with pytest.deprecated_call(
+        match="is deprecated and will be removed in a future version"
+    ):
+        lf.gather_every(n=n, offset=offset)
+
+
+@pytest.mark.parametrize("n", [1, 2, 3])
+@pytest.mark.parametrize("offset", [1, 2, 3])
+def test_gather_every_dask_v1(n: int, offset: int) -> None:
+    pytest.importorskip("dask")
+    import dask.dataframe as dd
+
+    df_v1 = nw.from_native(dd.from_pandas(pd.DataFrame(data)))
+    result = df_v1.gather_every(n=n, offset=offset)
+    expected = {"a": data["a"][offset::n]}
+    assert_equal_data(result, expected)

tests/from_numpy_test.py

@@ -8,7 +8,7 @@
 
 import narwhals as nw
 import narwhals.stable.v1 as nw_v1
-from tests.utils import Constructor
+from tests.utils import ConstructorEager
 from tests.utils import assert_equal_data
 
 if TYPE_CHECKING:
@@ -24,64 +24,52 @@
 }
 
 
-def test_from_numpy(constructor: Constructor, request: pytest.FixtureRequest) -> None:
-    if "dask" in str(constructor) or "pyspark" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
-    df = nw.from_native(constructor(data))
+def test_from_numpy(constructor_eager: ConstructorEager) -> None:
+    df = nw.from_native(constructor_eager(data))
     backend = nw.get_native_namespace(df)
     result = nw.from_numpy(arr, backend=backend)
     assert_equal_data(result, expected)
     assert isinstance(result, nw.DataFrame)
 
 
-def test_from_numpy_schema_dict(
-    constructor: Constructor, request: pytest.FixtureRequest
-) -> None:
-    if "dask" in str(constructor) or "pyspark" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
+def test_from_numpy_schema_dict(constructor_eager: ConstructorEager) -> None:
     schema = {
         "c": nw_v1.Int16(),
         "d": nw_v1.Float32(),
         "e": nw_v1.Int16(),
         "f": nw_v1.Float64(),
     }
-    df = nw_v1.from_native(constructor(data))
+    df = nw_v1.from_native(constructor_eager(data))
     backend = nw_v1.get_native_namespace(df)
     result = nw_v1.from_numpy(arr, backend=backend, schema=schema)
     assert result.collect_schema() == schema
 
 
-def test_from_numpy_schema_list(
-    constructor: Constructor, request: pytest.FixtureRequest
-) -> None:
-    if "dask" in str(constructor) or "pyspark" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
+def test_from_numpy_schema_list(constructor_eager: ConstructorEager) -> None:
     schema = ["c", "d", "e", "f"]
-    df = nw_v1.from_native(constructor(data))
+    df = nw_v1.from_native(constructor_eager(data))
     backend = nw_v1.get_native_namespace(df)
     result = nw_v1.from_numpy(arr, backend=backend, schema=schema)
     assert result.columns == schema
 
 
-def test_from_numpy_schema_notvalid(constructor: Constructor) -> None:
-    df = nw.from_native(constructor(data))
+def test_from_numpy_schema_notvalid(constructor_eager: ConstructorEager) -> None:
+    df = nw.from_native(constructor_eager(data))
     backend = nw_v1.get_native_namespace(df)
     with pytest.raises(TypeError, match=r"`schema.*expected.*types"):
         nw.from_numpy(arr, schema=5, backend=backend)  # type: ignore[arg-type]
 
 
-def test_from_numpy_v1(constructor: Constructor, request: pytest.FixtureRequest) -> None:
-    if "dask" in str(constructor) or "pyspark" in str(constructor):
-        request.applymarker(pytest.mark.xfail)
-    df = nw_v1.from_native(constructor(data))
+def test_from_numpy_v1(constructor_eager: ConstructorEager) -> None:
+    df = nw_v1.from_native(constructor_eager(data))
     backend = nw_v1.get_native_namespace(df)
     result = nw_v1.from_numpy(arr, backend=backend)
     assert_equal_data(result, expected)
     assert isinstance(result, nw_v1.DataFrame)
 
 
-def test_from_numpy_not2d(constructor: Constructor) -> None:
-    df = nw.from_native(constructor(data))
+def test_from_numpy_not2d(constructor_eager: ConstructorEager) -> None:
+    df = nw.from_native(constructor_eager(data))
     backend = nw_v1.get_native_namespace(df)
     with pytest.raises(ValueError, match="`from_numpy` only accepts 2D numpy arrays"):
         nw.from_numpy(np.array([0]), backend=backend)  # pyright: ignore[reportArgumentType]