File 4401-ets-improve-ets-new-2-already_exists-named_table-err.patch of Package erlang

From 53900d65ce8e7c246ed419ecbfc42ee4fe5956e9 Mon Sep 17 00:00:00 2001
From: Gonzalo Bella <gonzalobfmp@gmail.com>
Date: Thu, 29 Sep 2022 16:40:13 +0100
Subject: [PATCH] ets: improve ets:new/2 already_exists named_table error

Adds extra information in `erl_db.c` before returning the error for already
used table name. The error is only returned if the option `named_table`
is give and the name is already in use.

The extra information is used later to format the error message.

```
1> ets:new(ac_tab,[named_table]).
** exception error: bad argument
     in function  ets:new/2
        called as ets:new(ac_tab,[named_table])
        *** argument 1: table name already exists
```
---
 erts/emulator/beam/atom.names        |  1 +
 erts/emulator/beam/erl_db.c          |  4 +++-
 lib/stdlib/src/erl_stdlib_errors.erl | 14 ++++++++------
 lib/stdlib/test/ets_SUITE.erl        |  6 +++++-
 4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index 223603543f..c201268d03 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -90,6 +90,7 @@ atom allocator
 atom allocator_sizes
 atom alloc_util_allocators
 atom allow_passive_connect
+atom already_exists
 atom already_loaded
 atom amd64
 atom anchored
diff --git a/erts/emulator/beam/erl_db.c b/erts/emulator/beam/erl_db.c
index 3708019529..aa49291baa 100644
--- a/erts/emulator/beam/erl_db.c
+++ b/erts/emulator/beam/erl_db.c
@@ -57,6 +57,7 @@
 #define EXI_POSITION am_position /* The position is out of range. */
 #define EXI_OWNER    am_owner	 /* The receiving process is already the owner. */
 #define EXI_NOT_OWNER am_not_owner /* The current process is not the owner. */
+#define EXI_ALREADY_EXISTS am_already_exists /* The table identifier already exists. */
 
 #define DB_WRITE_CONCURRENCY_MIN_LOCKS 1
 #define DB_WRITE_CONCURRENCY_MAX_LOCKS 32768
@@ -2532,7 +2533,8 @@ BIF_RETTYPE ets_new_2(BIF_ALIST_2)
 	tb->common.meth->db_free_empty_table(tb);
 	db_unlock(tb,LCK_WRITE);
         table_dec_refc(tb, 0);
-	BIF_ERROR(BIF_P, BADARG);
+        BIF_P->fvalue = EXI_ALREADY_EXISTS;
+        BIF_ERROR(BIF_P, BADARG | EXF_HAS_EXT_INFO);
     }
 
     BIF_P->flags |= F_USING_DB; /* So we can remove tb if p dies */
diff --git a/lib/stdlib/src/erl_stdlib_errors.erl b/lib/stdlib/src/erl_stdlib_errors.erl
index 3298ee0f95..eeccb77db1 100644
--- a/lib/stdlib/src/erl_stdlib_errors.erl
+++ b/lib/stdlib/src/erl_stdlib_errors.erl
@@ -653,17 +653,19 @@ format_ets_error(match_spec_compile, [_], _Cause) ->
     [bad_matchspec];
 format_ets_error(next, Args, Cause) ->
     format_default(bad_key, Args, Cause);
-format_ets_error(new, [Name,Options], _Cause) ->
+format_ets_error(new, [Name,Options], Cause) ->
     NameError = if
                     is_atom(Name) -> [];
                     true -> not_atom
                 end,
     OptsError = must_be_list(Options),
-    case {NameError,OptsError} of
-        {[],[]} ->
-            [[],bad_options];
-        {_,_} ->
-            [NameError,OptsError]
+    case {NameError, OptsError, Cause} of
+        {[], [], already_exists} ->
+            [name_already_exists, []];
+        {[], [], _} ->
+            [[], bad_options];
+        {_, _, _} ->
+            [NameError, OptsError]
     end;
 format_ets_error(prev, Args, Cause) ->
     format_default(bad_key, Args, Cause);
diff --git a/lib/stdlib/test/ets_SUITE.erl b/lib/stdlib/test/ets_SUITE.erl
index 249a27bd02..99fe33dbff 100644
--- a/lib/stdlib/test/ets_SUITE.erl
+++ b/lib/stdlib/test/ets_SUITE.erl
@@ -8802,6 +8802,7 @@ error_info(_Config) ->
                                       end),
                            receive T -> T end
                    end,
+    _ = ets:new(name_already_exists, [named_table]),
 
     L = [{delete, ['$Tab']},
          {delete, ['$Tab', no_key], [no_fail]},
@@ -8886,6 +8887,8 @@ error_info(_Config) ->
          {new, [name, [a|b]], [no_table]},
          {new, [name, [a,b]], [no_table]},
          {new, [{bad,name}, [a,b]], [no_table]},
+         {new, [name_already_exists, [named_table]], [no_table,
+                                                      {error_term,already_exists}]},
 
          %% For a set, ets:next/2 and ets:prev/2 fails if the key does
          %% not exist.
@@ -9058,8 +9061,9 @@ ets_eval_bif_errors_once(F, Args, Opts) ->
     io:format("\n\n*** ets:~p/~p", [F,length(Args)]),
 
     NoFail = lists:member(no_fail, Opts),
+    ErrorTerm = proplists:get_value(error_term, Opts, none),
     case ets_apply(F, Args, Opts) of
-        {error,none} ->
+        {error,ErrorTerm} when not NoFail ->
             ok;
         {error,Info} ->
             store_error(wrong_failure_reason, MFA, Info);
-- 
2.35.3