fix: pl.repeat raise instead of panic if dtype can't be inferred

py-polars/src/functions/lazy.rs

@@ -451,7 +451,11 @@ pub fn repeat(value: PyExpr, n: PyExpr, dtype: Option<Wrap<DataType>>) -> PyResu
     }
 
     if let Expr::Literal(lv) = &value {
-        let av = lv.to_any_value().unwrap();
+        let av = lv.to_any_value().ok_or_else(||{
+            PyPolarsErr::from(polars_err!(ComputeError:
+                "The data type of the resulting column can't be inferred from the given value, please explicitly specify the dtype."
+            ))
+        })?;
         // Integer inputs that fit in Int32 are parsed as such
         if let DataType::Int64 = av.dtype() {
             let int_value = av.try_extract::<i64>().unwrap();

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

@@ -6,6 +6,7 @@
 import pytest
 
 import polars as pl
+from polars import ComputeError
 from polars.testing import assert_frame_equal, assert_series_equal
 
 
@@ -201,3 +202,8 @@ def test_repeat_by_none_13053(data: list[Any], expected_data: list[list[Any]]) -
     res = df.select(repeat=pl.col("x").repeat_by("by"))
     expected = pl.Series("repeat", expected_data)
     assert_series_equal(res.to_series(), expected)
+
+
+def test_repeat_raise() -> None:
+    with pytest.raises(ComputeError, match="please explicitly specify the dtype"):
+        pl.repeat([1, 2], n=2)