fix: Force nested struct missing equality (pola-rs#19031)

crates/polars-core/src/chunked_array/comparison/mod.rs

@@ -780,7 +780,7 @@ where
             .reduce(reduce)
             .unwrap();
 
-        if !is_missing & (a.null_count() > 0 || b.null_count() > 0) {
+        if !is_missing && (a.null_count() > 0 || b.null_count() > 0) {
             let mut a = a.into_owned();
             a.zip_outer_validity(&b);
             unsafe {
@@ -801,7 +801,7 @@ impl ChunkCompareEq<&StructChunked> for StructChunked {
         struct_helper(
             self,
             rhs,
-            |l, r| l.equal(r).unwrap(),
+            |l, r| l.equal_missing(r).unwrap(),
             |a, b| a.bitand(b),
             false,
             false,
@@ -823,7 +823,7 @@ impl ChunkCompareEq<&StructChunked> for StructChunked {
         struct_helper(
             self,
             rhs,
-            |l, r| l.not_equal(r).unwrap(),
+            |l, r| l.not_equal_missing(r).unwrap(),
             |a, b| a | b,
             true,
             false,

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

@@ -184,6 +184,25 @@ def test_struct_equality_18870() -> None:
     assert result == expected
 
 
+def test_struct_nested_equality() -> None:
+    df = pl.DataFrame(
+        {
+            "a": [{"foo": 0, "bar": "1"}, {"foo": None, "bar": "1"}, None],
+            "b": [{"foo": 0, "bar": "1"}] * 3,
+        }
+    )
+
+    # eq
+    ans = df.select(pl.col("a").eq(pl.col("b")))
+    expected = pl.DataFrame({"a": [True, False, None]})
+    assert_frame_equal(ans, expected)
+
+    # ne
+    ans = df.select(pl.col("a").ne(pl.col("b")))
+    expected = pl.DataFrame({"a": [False, True, None]})
+    assert_frame_equal(ans, expected)
+
+
 def isnan(x: Any) -> bool:
     return isinstance(x, float) and math.isnan(x)