Make RenameAlias serializable

crates/polars-plan/src/dsl/expr.rs

@@ -143,8 +143,6 @@ pub enum Expr {
     Len,
     /// Take the nth column in the `DataFrame`
     Nth(i64),
-    // skipped fields must be last otherwise serde fails in pickle
-    #[cfg_attr(feature = "serde", serde(skip))]
     RenameAlias {
         function: SpecialEq<Arc<dyn RenameAliasFn>>,
         expr: Arc<Expr>,

py-polars/tests/unit/cloud/test_prepare_cloud_plan.py

@@ -6,7 +6,7 @@
 
 import polars as pl
 from polars._utils.cloud import prepare_cloud_plan
-from polars.exceptions import ComputeError, InvalidOperationError
+from polars.exceptions import InvalidOperationError
 
 CLOUD_SOURCE = "s3://my-nonexistent-bucket/dataset"
 
@@ -50,6 +50,12 @@ def test_prepare_cloud_plan(lf: pl.LazyFrame) -> None:
         pl.LazyFrame({"a": [1, 2], "b": [3, 4]}).select(
             pl.col("a").map_elements(lambda x: sum(x), return_dtype=pl.Int64)
         ),
+        pl.LazyFrame({"a": [{"x": 1, "y": 2}]}).select(
+            pl.col("a").name.map(lambda x: x.upper())
+        ),
+        pl.LazyFrame({"a": [{"x": 1, "y": 2}]}).select(
+            pl.col("a").name.map_fields(lambda x: x.upper())
+        ),
     ],
 )
 def test_prepare_cloud_plan_udf(lf: pl.LazyFrame) -> None:
@@ -104,19 +110,3 @@ def test_prepare_cloud_plan_fail_on_python_scan(tmp_path: Path) -> None:
         match="logical plan ineligible for execution on Polars Cloud",
     ):
         prepare_cloud_plan(lf)
-
-
-@pytest.mark.parametrize(
-    "lf",
-    [
-        pl.LazyFrame({"a": [{"x": 1, "y": 2}]}).select(
-            pl.col("a").name.map(lambda x: x.upper())
-        ),
-        pl.LazyFrame({"a": [{"x": 1, "y": 2}]}).select(
-            pl.col("a").name.map_fields(lambda x: x.upper())
-        ),
-    ],
-)
-def test_prepare_cloud_plan_fail_on_serialization(lf: pl.LazyFrame) -> None:
-    with pytest.raises(ComputeError, match="serialize"):
-        prepare_cloud_plan(lf)