sqllogictests & type inheritance

datafusion/core/tests/sqllogictests/test_files/nullif.slt

@@ -0,0 +1,98 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+
+#   http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+statement ok
+CREATE TABLE test(
+  int_field  INT,
+  bool_field BOOLEAN,
+  text_field TEXT,
+  more_ints  INT
+) as VALUES
+  (1,    true,  'abc',  2),
+  (2,    false, 'def',  2),
+  (3,    NULL,  'ghij', 3),
+  (NULL, NULL,   NULL,  4),
+  (4,    false, 'zxc',  5),
+  (NULL, true,   NULL,  6)
+;
+
+# Basic arrays tests
+query T
+SELECT NULLIF(int_field, 2) FROM test;
+----
+1
+NULL
+3
+NULL
+4
+NULL
+
+query T
+SELECT NULLIF(bool_field, false) FROM test;
+----
+true
+NULL
+NULL
+NULL
+NULL
+true
+
+query T
+SELECT NULLIF(text_field, 'zxc') FROM test;
+----
+abc
+def
+ghij
+NULL
+NULL
+NULL
+
+query T
+SELECT NULLIF(int_field, more_ints) FROM test;
+----
+1
+NULL
+NULL
+NULL
+4
+NULL
+
+query T
+SELECT NULLIF(3, int_field) FROM test;
+----
+3
+3
+NULL
+3
+3
+3
+
+# Scalar values tests
+query T
+SELECT NULLIF(1, 1);
+----
+NULL
+
+query T
+SELECT NULLIF(1, 3);
+----
+1
+
+query T
+SELECT NULLIF(NULL, NULL);
+----
+NULL

datafusion/physical-expr/src/expressions/nullif.rs

@@ -62,8 +62,8 @@ pub fn nullif_func(args: &[ColumnarValue]) -> Result<ColumnarValue> {
             Ok(ColumnarValue::Array(array))
         }
         (ColumnarValue::Scalar(lhs), ColumnarValue::Scalar(rhs)) => {
-            let val = match lhs.eq(rhs) {
-                true => ScalarValue::Null,
+            let val: ScalarValue = match lhs.eq(rhs) {
+                true => lhs.get_datatype().try_into()?,
                 false => lhs.clone(),
             };
 
@@ -210,7 +210,7 @@ mod tests {
         let result_eq = nullif_func(&[a_eq, b_eq])?;
         let result_eq = result_eq.into_array(1);
 
-        let expected_eq = Arc::new(NullArray::new(1)) as ArrayRef;
+        let expected_eq = Arc::new(Int32Array::from(vec![None])) as ArrayRef;
 
         assert_eq!(expected_eq.as_ref(), result_eq.as_ref());