fix(rust): ensure eq for BinaryViewArray checks all elements (pol…

…a-rs#15268)

crates/polars-arrow/src/array/binview/mod.rs

@@ -120,7 +120,7 @@ pub struct BinaryViewArrayGeneric<T: ViewType + ?Sized> {
 
 impl<T: ViewType + ?Sized> PartialEq for BinaryViewArrayGeneric<T> {
     fn eq(&self, other: &Self) -> bool {
-        self.into_iter().zip(other).all(|(l, r)| l == r)
+        self.len() == other.len() && self.into_iter().zip(other).all(|(l, r)| l == r)
     }
 }
 

py-polars/tests/unit/datatypes/test_enum.py

@@ -214,8 +214,8 @@ def test_append_to_an_enum() -> None:
 
 def test_append_to_an_enum_with_new_category() -> None:
     with pytest.raises(
-        pl.ComputeError,
-        match=("can not merge incompatible Enum types"),
+        pl.SchemaError,
+        match=("cannot extend/append Enum"),
     ):
         pl.Series([None, "a", "b", "c"], dtype=pl.Enum(["a", "b", "c"])).append(
             pl.Series(["d", "a", "b", "c"], dtype=pl.Enum(["a", "b", "c", "d"]))
@@ -469,7 +469,36 @@ def test_enum_cse_eq() -> None:
     dt1 = pl.Enum(["a", "b"])
     dt2 = pl.Enum(["a", "c"])
 
-    df.lazy().select(
-        pl.when(True).then(pl.lit("a", dtype=dt1)).alias("dt1"),
-        pl.when(True).then(pl.lit("a", dtype=dt2)).alias("dt2"),
-    ).collect()
+    out = (
+        df.lazy()
+        .select(
+            pl.when(True).then(pl.lit("a", dtype=dt1)).alias("dt1"),
+            pl.when(True).then(pl.lit("a", dtype=dt2)).alias("dt2"),
+        )
+        .collect()
+    )
+
+    assert out["dt1"].item() == "a"
+    assert out["dt2"].item() == "a"
+    assert out["dt1"].dtype == pl.Enum(["a", "b"])
+    assert out["dt2"].dtype == pl.Enum(["a", "c"])
+    assert out["dt1"].dtype != out["dt2"].dtype
+
+
+def test_category_comparison_subset() -> None:
+    dt1 = pl.Enum(["a"])
+    dt2 = pl.Enum(["a", "b"])
+    out = (
+        pl.LazyFrame()
+        .select(
+            pl.lit("a", dtype=dt1).alias("dt1"),
+            pl.lit("a", dtype=dt2).alias("dt2"),
+        )
+        .collect()
+    )
+
+    assert out["dt1"].item() == "a"
+    assert out["dt2"].item() == "a"
+    assert out["dt1"].dtype == pl.Enum(["a"])
+    assert out["dt2"].dtype == pl.Enum(["a", "b"])
+    assert out["dt1"].dtype != out["dt2"].dtype

py-polars/tests/unit/operations/test_replace.py

@@ -94,7 +94,7 @@ def test_replace_enum_to_new_enum() -> None:
     new_dtype = pl.Enum(["a", "b", "c", "d", "e"])
     new = pl.Series(["c", "e"], dtype=new_dtype)
 
-    result = s.replace(old, new)
+    result = s.replace(old, new, return_dtype=new_dtype)
 
     expected = pl.Series(["c", "e", "c"], dtype=new_dtype)
     assert_series_equal(result, expected)