fix nested min max (#2465)

pola-rs · Jan 25, 2022 · ebcc035 · ebcc035
1 parent 0a8ede9
commit ebcc035
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Showing 2 changed files with 9 additions and 2 deletions.
diff --git a/polars/polars-lazy/src/functions.rs b/polars/polars-lazy/src/functions.rs
@@ -593,7 +593,7 @@ fn max_exprs_impl(mut exprs: Vec<Expr>) -> Expr {
         .map_many(
             |s| {
                 let s = s.to_vec();
-                let df = DataFrame::new(s)?;
+                let df = DataFrame::new_no_checks(s);
                 df.hmax().map(|s| s.unwrap())
             },
             &exprs[1..],
@@ -618,7 +618,7 @@ fn min_exprs_impl(mut exprs: Vec<Expr>) -> Expr {
         .map_many(
             |s| {
                 let s = s.to_vec();
-                let df = DataFrame::new(s)?;
+                let df = DataFrame::new_no_checks(s);
                 df.hmin().map(|s| s.unwrap())
             },
             &exprs[1..],

diff --git a/py-polars/tests/test_lazy.py b/py-polars/tests/test_lazy.py
@@ -1132,3 +1132,10 @@ def test_lower_bound_upper_bound(fruits_cars: pl.DataFrame) -> None:
     assert res_expr["A"][0] < -10_000_000
     res_expr = fruits_cars.select(pl.col("A").upper_bound())
     assert res_expr["A"][0] > 10_000_000
+
+
+def test_nested_min_max() -> None:
+    df = pl.DataFrame({"a": [1], "b": [2], "c": [3], "d": [4]})
+    out = df.with_column(pl.max([pl.min(["a", "b"]), pl.min(["c", "d"])]).alias("t"))
+    assert out.shape == (1, 5)
+    assert out["t"][0] == 3