On 2019-10-17 10:06, Eli Zaretskii wrote:
>> Cc: rpluim@gmail.com, 37785@debbugs.gnu.org
>> From: Clément Pit-Claudel <cpitclaudel@gmail.com>
>> Date: Thu, 17 Oct 2019 09:47:52 -0400
>>
>>> But show-help-function is for showing help-echo, is it not?
>>
>> That's true, and my explanation wasn't very good.  I'm working off of this commit:
>>
>> commit 5f5fe275ec54194a9293690ffee3d425026ac14b
>> Author: Paul Eggert <eggert@cs.ucla.edu>
>> Date:   Sun Aug 2 14:55:15 2015 -0700
>>
>>     Treat help strings like other doc strings
>>     
>>     * doc/lispref/text.texi (Special Properties), etc/NEWS: Document this.
>>     * lisp/epa.el (epa--select-keys): Remove no-longer-needed calls to
>>     substitute-command-keys.
>>     * src/keyboard.c (show_help_echo, parse_menu_item): Call
>>     substitute-command-keys on the help string before displaying it.
>>
>> It adds Fsubstitute_command_keys in two places: show_help_echo and parse_menu_item.  The patch I sent makes both of these calls conditional, so calling the variable help-echo-inhibit-substitutions isn't right.
> 
> Why isn't it right for parse_menu_item?  That function uses the :help
> text, which is help-echo for menu items.

Ah, OK, then I just misunderstood :)
I've attached an updated patch.