Deprecate ScalarUDFImpl::return_type

datafusion/expr/src/udf.rs

@@ -174,6 +174,7 @@ impl ScalarUDF {
     ///
     /// See [`ScalarUDFImpl::return_type`] for more details.
     pub fn return_type(&self, arg_types: &[DataType]) -> Result<DataType> {
+        #[allow(deprecated)]
         self.inner.return_type(arg_types)
     }
 
@@ -450,6 +451,7 @@ pub trait ScalarUDFImpl: Debug + Send + Sync {
     /// is recommended to return [`DataFusionError::Internal`].
     ///
     /// [`DataFusionError::Internal`]: datafusion_common::DataFusionError::Internal
+    #[deprecated(since = "44.0.0", note = "Use `return_type_from_exprs` instead")]
     fn return_type(&self, arg_types: &[DataType]) -> Result<DataType>;
 
     /// What [`DataType`] will be returned by this function, given the
@@ -483,6 +485,7 @@ pub trait ScalarUDFImpl: Debug + Send + Sync {
         _schema: &dyn ExprSchema,
         arg_types: &[DataType],
     ) -> Result<DataType> {
+        #[allow(deprecated)]
         self.return_type(arg_types)
     }
 
@@ -756,6 +759,7 @@ impl ScalarUDFImpl for AliasedScalarUDFImpl {
     }
 
     fn return_type(&self, arg_types: &[DataType]) -> Result<DataType> {
+        #[allow(deprecated)]
         self.inner.return_type(arg_types)
     }
 

datafusion/functions/src/string/concat.rs

@@ -305,6 +305,7 @@ pub fn simplify_concat(args: Vec<Expr>) -> Result<ExprSimplifyResult> {
                 _ => None,
             })
             .collect();
+        #[allow(deprecated)]
         ConcatFunc::new().return_type(&data_types)
     }?;