bug#36886: 26.2; (global-eldoc-mode -1) should disable eldoc completely

[Dmitry Gutov <dgutov@yandex.ru>]

On 01.08.2019 14:37, Basil L. Contovounesios wrote:
> Sanel Zukan <sanelz@gmail.com> writes:
> 
>> When Emacs is run with (global-eldoc-mode -1), eldoc is not completely
>> disabled because it will show function arguments inside mode-line.
>>
>> I believe intention behind (global-eldoc-mode -1) should be that all
>> eldoc facility gets disabled. Right now, the only way to stop poping
>> stuff in mode-line is this:
>>
>>   (setq-default eldoc-message-function 'ignore)
> 
> CCing Dmitry, who explicitly enabled eldoc-mode in read--expression as
> part of bug#27202: https://debbugs.gnu.org/27202.
> 
> My gut says that bug should be fixable within eldoc.el, without having
> to tweak read--expression, but I'm not familiar with eldoc.

I'm not sure what's the best way. But this should help:

diff --git a/lisp/simple.el b/lisp/simple.el
index 0bc39f08c0..4eec9e732d 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -1583,7 +1583,8 @@ read--expression
            ;; FIXME: call emacs-lisp-mode?
            (add-function :before-until (local 
'eldoc-documentation-function)
                          #'elisp-eldoc-documentation-function)
-          (eldoc-mode 1)
+          (when global-eldoc-mode
+            (eldoc-mode 1))
            (add-hook 'completion-at-point-functions
                      #'elisp-completion-at-point nil t)
            (run-hooks 'eval-expression-minibuffer-setup-hook))