chore: simplify broadcast for spark-like and ibis (#2595)

* chore: simplify `broadcast` for spark-like and ibis

* duckdb too

Author: MarcoGorelli

narwhals/_duckdb/expr.py

@@ -162,19 +162,8 @@ def broadcast(self, kind: Literal[ExprKind.AGGREGATION, ExprKind.LITERAL]) -> Se
         if self._backend_version < (1, 3):
             msg = "At least version 1.3 of DuckDB is required for binary operations between aggregates and columns."
             raise NotImplementedError(msg)
-
         template = "{expr} over ()"
-
-        def func(df: DuckDBLazyFrame) -> Sequence[Expression]:
-            return [SQLExpression(template.format(expr=expr)) for expr in self(df)]
-
-        return self.__class__(
-            func,
-            evaluate_output_names=self._evaluate_output_names,
-            alias_output_names=self._alias_output_names,
-            backend_version=self._backend_version,
-            version=self._version,
-        )
+        return self._with_callable(lambda expr: SQLExpression(template.format(expr=expr)))
 
     @classmethod
     def from_column_names(

narwhals/_ibis/expr.py

@@ -7,7 +7,6 @@
 from ibis import _ as col
 
 from narwhals._compliant import LazyExpr
-from narwhals._expression_parsing import ExprKind
 from narwhals._ibis.expr_dt import IbisExprDateTimeNamespace
 from narwhals._ibis.expr_list import IbisExprListNamespace
 from narwhals._ibis.expr_str import IbisExprStringNamespace
@@ -20,7 +19,7 @@
     from typing_extensions import Self
 
     from narwhals._compliant.typing import AliasNames, EvalNames, EvalSeries
-    from narwhals._expression_parsing import ExprMetadata
+    from narwhals._expression_parsing import ExprKind, ExprMetadata
     from narwhals._ibis.dataframe import IbisLazyFrame
     from narwhals._ibis.namespace import IbisNamespace
     from narwhals._ibis.typing import ExprT, WindowFunction
@@ -149,19 +148,8 @@ def func(window_inputs: WindowInputs) -> ir.Value:
         return func
 
     def broadcast(self, kind: Literal[ExprKind.AGGREGATION, ExprKind.LITERAL]) -> Self:
-        if kind is ExprKind.LITERAL:
-            return self
-
-        def func(df: IbisLazyFrame) -> Sequence[ir.Value]:
-            return [expr.over() for expr in self(df)]
-
-        return self.__class__(
-            func,
-            evaluate_output_names=self._evaluate_output_names,
-            alias_output_names=self._alias_output_names,
-            backend_version=self._backend_version,
-            version=self._version,
-        )
+        # Ibis does its own broadcasting.
+        return self
 
     @classmethod
     def from_column_names(

narwhals/_spark_like/expr.py

@@ -106,18 +106,7 @@ def __call__(self, df: SparkLikeLazyFrame) -> Sequence[Column]:
     def broadcast(self, kind: Literal[ExprKind.AGGREGATION, ExprKind.LITERAL]) -> Self:
         if kind is ExprKind.LITERAL:
             return self
-
-        def func(df: SparkLikeLazyFrame) -> Sequence[Column]:
-            return [result.over(self.partition_by()) for result in self(df)]
-
-        return self.__class__(
-            func,
-            evaluate_output_names=self._evaluate_output_names,
-            alias_output_names=self._alias_output_names,
-            backend_version=self._backend_version,
-            version=self._version,
-            implementation=self._implementation,
-        )
+        return self._with_callable(lambda expr: expr.over(self.partition_by()))
 
     @property
     def _F(self):  # type: ignore[no-untyped-def] # noqa: ANN202, N802