chore: remove deprecated ScalarUDF / ScalarUDFImpl methods past the API health policy

datafusion/expr/src/udf.rs

@@ -28,7 +28,7 @@ use arrow::datatypes::{DataType, Field, FieldRef};
 #[cfg(debug_assertions)]
 use datafusion_common::assert_or_internal_err;
 use datafusion_common::config::ConfigOptions;
-use datafusion_common::{ExprSchema, Result, ScalarValue, not_impl_err};
+use datafusion_common::{Result, ScalarValue, not_impl_err};
 use datafusion_expr_common::dyn_eq::{DynEq, DynHash};
 use datafusion_expr_common::interval_arithmetic::Interval;
 use datafusion_expr_common::placement::ExpressionPlacement;
@@ -183,18 +183,6 @@ impl ScalarUDF {
         self.inner.name()
     }
 
-    /// Returns this function's display_name.
-    ///
-    /// See [`ScalarUDFImpl::display_name`] for more details
-    #[deprecated(
-        since = "50.0.0",
-        note = "This method is unused and will be removed in a future release"
-    )]
-    pub fn display_name(&self, args: &[Expr]) -> Result<String> {
-        #[expect(deprecated)]
-        self.inner.display_name(args)
-    }
-
     /// Returns this function's schema_name.
     ///
     /// See [`ScalarUDFImpl::schema_name`] for more details
@@ -255,12 +243,6 @@ impl ScalarUDF {
         self.inner.simplify(args, info)
     }
 
-    #[deprecated(since = "50.0.0", note = "Use `return_field_from_args` instead.")]
-    pub fn is_nullable(&self, args: &[Expr], schema: &dyn ExprSchema) -> bool {
-        #[expect(deprecated)]
-        self.inner.is_nullable(args, schema)
-    }
-
     /// Return a preimage
     ///
     /// See [`ScalarUDFImpl::preimage`] for more details.
@@ -551,22 +533,6 @@ pub trait ScalarUDFImpl: Debug + DynEq + DynHash + Send + Sync + Any {
         &[]
     }
 
-    /// Returns the user-defined display name of function, given the arguments
-    ///
-    /// This can be used to customize the output column name generated by this
-    /// function.
-    ///
-    /// Defaults to `name(args[0], args[1], ...)`
-    #[deprecated(
-        since = "50.0.0",
-        note = "This method is unused and will be removed in a future release"
-    )]
-    fn display_name(&self, args: &[Expr]) -> Result<String> {
-        let names: Vec<String> = args.iter().map(ToString::to_string).collect();
-        // TODO: join with ", " to standardize the formatting of Vec<Expr>, <https://github.com/apache/datafusion/issues/10364>
-        Ok(format!("{}({})", self.name(), names.join(",")))
-    }
-
     /// Returns the name of the column this expression would create
     ///
     /// See [`Expr::schema_name`] for details
@@ -698,14 +664,6 @@ pub trait ScalarUDFImpl: Debug + DynEq + DynHash + Send + Sync + Any {
         Ok(Arc::new(Field::new(self.name(), return_type, true)))
     }
 
-    #[deprecated(
-        since = "45.0.0",
-        note = "Use `return_field_from_args` instead. if you use `is_nullable` that returns non-nullable with `return_type`, you would need to switch to `return_field_from_args`, you might have error"
-    )]
-    fn is_nullable(&self, _args: &[Expr], _schema: &dyn ExprSchema) -> bool {
-        true
-    }
-
     /// Returns true if this function always returns NULL when any argument is
     /// NULL.
     ///
@@ -1112,11 +1070,6 @@ impl ScalarUDFImpl for AliasedScalarUDFImpl {
         self.inner.name()
     }
 
-    fn display_name(&self, args: &[Expr]) -> Result<String> {
-        #[expect(deprecated)]
-        self.inner.display_name(args)
-    }
-
     fn schema_name(&self, args: &[Expr]) -> Result<String> {
         self.inner.schema_name(args)
     }
@@ -1133,11 +1086,6 @@ impl ScalarUDFImpl for AliasedScalarUDFImpl {
         self.inner.return_field_from_args(args)
     }
 
-    fn is_nullable(&self, args: &[Expr], schema: &dyn ExprSchema) -> bool {
-        #[expect(deprecated)]
-        self.inner.is_nullable(args, schema)
-    }
-
     fn is_strict(&self) -> bool {
         self.inner.is_strict()
     }

datafusion/functions-nested/src/extract.rs

@@ -135,15 +135,6 @@ impl ScalarUDFImpl for ArrayElement {
         "array_element"
     }
 
-    fn display_name(&self, args: &[Expr]) -> Result<String> {
-        let args_name = args.iter().map(ToString::to_string).collect::<Vec<_>>();
-        if args_name.len() != 2 {
-            return exec_err!("expect 2 args, got {}", args_name.len());
-        }
-
-        Ok(format!("{}[{}]", args_name[0], args_name[1]))
-    }
-
     fn schema_name(&self, args: &[Expr]) -> Result<String> {
         let args_name = args
             .iter()
@@ -351,15 +342,6 @@ impl ArraySlice {
 }
 
 impl ScalarUDFImpl for ArraySlice {
-    fn display_name(&self, args: &[Expr]) -> Result<String> {
-        let args_name = args.iter().map(ToString::to_string).collect::<Vec<_>>();
-        if let Some((arr, indexes)) = args_name.split_first() {
-            Ok(format!("{arr}[{}]", indexes.join(":")))
-        } else {
-            exec_err!("no argument")
-        }
-    }
-
     fn schema_name(&self, args: &[Expr]) -> Result<String> {
         let args_name = args
             .iter()

datafusion/functions/src/core/getfield.rs

@@ -380,26 +380,6 @@ impl ScalarUDFImpl for GetFieldFunc {
         "get_field"
     }
 
-    fn display_name(&self, args: &[Expr]) -> Result<String> {
-        if args.len() < 2 {
-            return exec_err!(
-                "get_field requires at least 2 arguments, got {}",
-                args.len()
-            );
-        }
-
-        let base = &args[0];
-        let field_names: Vec<String> = args[1..]
-            .iter()
-            .map(|f| match f {
-                Expr::Literal(name, _) => name.to_string(),
-                other => other.schema_name().to_string(),
-            })
-            .collect();
-
-        Ok(format!("{}[{}]", base, field_names.join("][")))
-    }
-
     fn schema_name(&self, args: &[Expr]) -> Result<String> {
         if args.len() < 2 {
             return exec_err!(