fix docttest

py-polars/polars/_utils/construction/dataframe.py

@@ -63,7 +63,7 @@
     from polars.polars import PyDataFrame
 
 if TYPE_CHECKING:
-    from polars import DataFrame, Series
+    from polars import DataFrame, Expr, Series
     from polars._typing import (
         Orientation,
         PolarsDataType,
@@ -1212,15 +1212,22 @@ def arrow_to_pydf(
     if rechunk:
         pydf = pydf.rechunk()
 
+    def broadcastable_s(s: Series, name: str) -> Expr:
+        if s.len() == 1:
+            return F.lit(s).first().alias(name)
+        return F.lit(s).alias(name)
+
     reset_order = False
     if len(dictionary_cols) > 0:
         df = wrap_df(pydf)
-        df = df.with_columns([F.lit(s).alias(s.name) for s in dictionary_cols.values()])
+        df = df.with_columns(
+            [broadcastable_s(s, name) for s in dictionary_cols.values()]
+        )
         reset_order = True
 
     if len(struct_cols) > 0:
         df = wrap_df(pydf)
-        df = df.with_columns([F.lit(s).alias(s.name) for s in struct_cols.values()])
+        df = df.with_columns([broadcastable_s(s, name) for s in struct_cols.values()])
         reset_order = True
 
     if reset_order:

py-polars/polars/expr/expr.py

@@ -1723,15 +1723,14 @@ def mode(self) -> Expr:
         ...         "b": [1, 1, 2, 2],
         ...     }
         ... )
-        >>> df.select(pl.all().mode())  # doctest: +IGNORE_RESULT
+        >>> df.select(pl.all().mode().first())  # doctest: +IGNORE_RESULT
         shape: (2, 2)
         ┌─────┬─────┐
         │ a   ┆ b   │
         │ --- ┆ --- │
         │ i64 ┆ i64 │
         ╞═════╪═════╡
         │ 1   ┆ 1   │
-        │ 1   ┆ 2   │
         └─────┴─────┘
         """
         return self._from_pyexpr(self._pyexpr.mode())

py-polars/tests/unit/dataframe/test_df.py

@@ -1999,7 +1999,7 @@ def test_add_string() -> None:
 
 def test_df_broadcast() -> None:
     df = pl.DataFrame({"a": [1, 2, 3]}, schema_overrides={"a": pl.UInt8})
-    out = df.with_columns(pl.Series("s", [[1, 2]]))
+    out = df.with_columns(pl.lit(pl.Series("s", [[1, 2]])).first())
     assert out.shape == (3, 2)
     assert out.schema == {"a": pl.UInt8, "s": pl.List(pl.Int64)}
     assert out.rows() == [(1, [1, 2]), (2, [1, 2]), (3, [1, 2])]

py-polars/tests/unit/functions/test_lit.py

@@ -27,7 +27,7 @@
 )
 def test_lit_list_input(input: list[Any]) -> None:
     df = pl.DataFrame({"a": [1, 2]})
-    result = df.with_columns(pl.lit(input))
+    result = df.with_columns(pl.lit(input).first())
     expected = pl.DataFrame({"a": [1, 2], "literal": [input, input]})
     assert_frame_equal(result, expected)
 
@@ -41,7 +41,7 @@ def test_lit_list_input(input: list[Any]) -> None:
 )
 def test_lit_tuple_input(input: tuple[Any, ...]) -> None:
     df = pl.DataFrame({"a": [1, 2]})
-    result = df.with_columns(pl.lit(input))
+    result = df.with_columns(pl.lit(input).first())
 
     expected = pl.DataFrame({"a": [1, 2], "literal": [list(input), list(input)]})
     assert_frame_equal(result, expected)