Schedule old style type tests for removal in OTP 30

Author: richcarl

lib/stdlib/src/erl_lint.erl

@@ -393,7 +393,10 @@ format_error_1({removed_type, MNA, String}) ->
 format_error_1({removed_callback, MNA, String}) ->
     {~"the callback ~s is removed; ~s", [format_mna(MNA), String]};
 format_error_1({obsolete_guard, {F, A}}) ->
-    {~"~p/~p obsolete (use is_~p/~p)", [F, A, F, A]};
+    {~"""
+      ~p/~p as a type test is obsolete and will be
+      removed in OTP 30; use is_~p/~p instead.
+      """, [F, A, F, A]};
 format_error_1({obsolete_guard_overridden,Test}) ->
     {~"""
       obsolete ~s/1 (meaning is_~s/1) is illegal when there is a

system/doc/general_info/scheduled_for_removal_30.md

@@ -1,12 +1,35 @@
 <!--
-%CopyrightBegin%
-
-SPDX-License-Identifier: Apache-2.0
+%% %CopyrightBegin%
+%%
+%% SPDX-License-Identifier: Apache-2.0
+%%
+%% Copyright Ericsson AB 2024-2025. All Rights Reserved.
+%%
+%% Licensed 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.
+%%
+%% %CopyrightEnd%
+-->
 
-Copyright Ericsson AB 2025. All Rights Reserved.
+### Old aliases for type tests in guards
 
-%CopyrightEnd%
--->
+The aliases `atom/1`, `tuple/1`, etc., for the respective type tests
+`is_atom/1`, `is_tuple/1`, etc., have been deprecated since before OTP R13
+and have been scheduled for removal in OTP 30. Note that these aliases only
+could be used as guard tests at the top level. For example, in `{X, Y} when
+float(X), X =:= float(Y) -> ...` the first use of `float/1` is a type test
+alias, but the second use is the normal integer-to-float conversion BIF,
+because it occurs inside the `=:=`. The aliases were never recognized
+outside guards.
 
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