test: refactor test_data_color_utils.py through parametrization

tests/conftest.py

@@ -0,0 +1,71 @@
+from __future__ import annotations
+
+from importlib.util import find_spec
+
+import pytest
+
+from great_tables._tbl_data import DataFrameLike, _re_version
+from tests.utils import DataFrameConstructor, DataLike
+
+
+def pandas_constructor(obj: DataLike) -> DataFrameLike:
+    import pandas as pd
+
+    return pd.DataFrame(obj)  # type: ignore[no-any-return]
+
+
+def pandas_nullable_constructor(obj: DataLike) -> DataFrameLike:
+    import pandas as pd
+
+    return pd.DataFrame(obj).convert_dtypes(dtype_backend="numpy_nullable")  # type: ignore[no-any-return]
+
+
+def pandas_pyarrow_constructor(obj: DataLike) -> DataFrameLike:
+    import pandas as pd
+
+    return pd.DataFrame(obj).convert_dtypes(dtype_backend="pyarrow")  # type: ignore[no-any-return]
+
+
+def polars_constructor(obj: DataLike) -> DataFrameLike:
+    import polars as pl
+
+    return pl.DataFrame(obj)
+
+
+def pyarrow_table_constructor(obj: DataLike) -> DataFrameLike:
+    import pyarrow as pa
+
+    return pa.table(obj)  # type: ignore[no-any-return]
+
+
+frame_constructors: list[DataFrameConstructor] = []
+
+is_pandas_installed = find_spec("pandas") is not None
+is_polars_installed = find_spec("polars") is not None
+is_pyarrow_installed = find_spec("pyarrow") is not None
+
+if is_pandas_installed:
+    import pandas as pd
+
+    frame_constructors.append(pandas_constructor)
+
+    pandas_ge_v2 = _re_version(pd.__version__) >= (2, 0, 0)
+
+    if pandas_ge_v2:
+        frame_constructors.append(pandas_nullable_constructor)
+
+    if pandas_ge_v2 and is_pyarrow_installed:
+        # pandas 2.0+ supports pyarrow dtype backend
+        # https://pandas.pydata.org/docs/whatsnew/v2.0.0.html#new-dtype-backends
+        frame_constructors.append(pandas_pyarrow_constructor)
+
+if is_polars_installed:
+    frame_constructors.append(polars_constructor)
+
+if is_pyarrow_installed:
+    frame_constructors.append(pyarrow_table_constructor)
+
+
+@pytest.fixture(params=frame_constructors)
+def frame_constructor(request: pytest.FixtureRequest) -> DataFrameConstructor:
+    return request.param  # type: ignore[no-any-return]