bug#48153: 28.0.50; minor mode keymaps should not override keymap given to read-from-minibuffer

[Jimmy Yuen Ho Wong]

Sorry I missed a reproduction step. You have to turn on the minor mode for the 
minibuffers. In my config there actually is a global minor mode that turns the 
minor mode on even for the minibuffer.

In Emacs 27, turning the minor mode on inside the minibuffer would not override 
the key map given to read-from-minibuffer.

I was able to reproduce this on a pristine init.el with just these reproduction 
steps plus turning the minor mode on for all buffers with a global minor mode.

My emacs has native compilation configured if that helps.

> On 3 May 2021, at 4:15 pm, Gregory Heytings <gregory@heytings.org> wrote:
> 
> 
>> 
>> After typing C-x b or C-x C-f, the minor mode maps from the buffer that 
>> launched the minibuffer will override the keymap given to 
>> `read-from-minibuffer`, this seems to be a regression in emacs 28 master.
>> 
>> Reproduction:
>> 
>> 1. Turn on `ido-mode`
>> 2. Turn on some minor mode that rebinds `C-k` with `(define-key
>> some-minor-mode-map (kbd "C-k") 'some-func)`
>> 3. C-x b
>> 4. Select a buffer and type C-k
>> 
>> Expectation:
>> 
>> C-k should be bound to `ido-kill-buffer-at-head` and calls it, but instead 
>> `some-func` is called.
>> 
>> Since C-k is bound in `ido-completion-map`, and it is given to 
>> `read-from-minibuffer`, all the bindings in `ido-completion-map` should take 
>> precedence.
>> 
> 
> Thanks for your bug report.  I'm unable to reproduce your recipe on recent 
> versions of the trunk (today, a week ago).  I tried
> 
> (define-minor-mode test-mode "" :keymap (let ((map (make-sparse-keymap))) 
> (define-key map (kbd "C-k") '(lambda () (interactive) (message "BAD !"))) 
> map))
> 
> and C-k is indeed bound to 'ido-kill-buffer-at-head'.  I suspect this 
> misbehavior is due to your configuration; if not, could you try to create a 
> recipe starting with emacs -Q?