chore: attach diagnostic to unary_op PLUS

Author: onlyjackfrost

datafusion/sql/src/expr/unary_op.rs

@@ -16,7 +16,7 @@
 // under the License.
 
 use crate::planner::{ContextProvider, PlannerContext, SqlToRel};
-use datafusion_common::{not_impl_err, plan_err, DFSchema, Result};
+use datafusion_common::{not_impl_err, plan_err, DFSchema, Diagnostic, Result};
 use datafusion_expr::{
     type_coercion::{is_interval, is_timestamp},
     Expr, ExprSchemable,
@@ -45,7 +45,13 @@ impl<S: ContextProvider> SqlToRel<'_, S> {
                 {
                     Ok(operand)
                 } else {
-                    plan_err!("Unary operator '+' only supports numeric, interval and timestamp types")
+                    plan_err!("Unary operator '+' only supports numeric, interval and timestamp types").map_err(|e| {
+                        let spans = operand.spans();
+                        let span = if let Some(s) = spans.as_ref() { s.first() } else { None };
+                        let diagnostic =
+                        Diagnostic::new_error(format!("Unary operator '+' only supports numeric, interval and timestamp types"), span);
+                        e.with_diagnostic(diagnostic)
+                    })
                 }
             }
             UnaryOperator::Minus => {

datafusion/sql/tests/cases/diagnostic.rs

@@ -286,3 +286,31 @@ fn test_invalid_function() -> Result<()> {
     assert_eq!(diag.span, Some(spans["whole"]));
     Ok(())
 }
+
+#[test]
+fn test_unary_op_plus_with_non_column() -> Result<()> {
+    // create a table with a column of type varchar
+    let query = "SELECT /*whole*/+'a'/*whole*/ ";
+    let spans = get_spans(query);
+    let diag = do_query(query);
+    assert_eq!(
+        diag.message,
+        "Unary operator '+' only supports numeric, interval and timestamp types"
+    );
+    assert_eq!(diag.span, None);
+    Ok(())
+}
+
+#[test]
+fn test_unary_op_plus_with_column() -> Result<()> {
+    // Test with a direct query that references a column with an incompatible type
+    let query = "SELECT +/*whole*/first_name/*whole*/ FROM person";
+    let spans = get_spans(query);
+    let diag = do_query(query);
+    assert_eq!(
+        diag.message,
+        "Unary operator '+' only supports numeric, interval and timestamp types"
+    );
+    assert_eq!(diag.span, Some(spans["whole"]));
+    Ok(())
+}