bug#45474: Icomplete exhibiting in recursive minibuffer when it shouldn’t

[Dario Gjorgjevski]

How to reproduce from emacs -Q:

  (setq enable-recursive-minibuffers t)
  (setq icomplete-show-matches-on-no-input t)
  M-x icomplete-mode RET
  C-x C-f
    [Icomplete now exhibits some filenames in the minibuffer]
  M-:
    [Icomplete shouldn’t exhibit anything here but it still
     exhibits the filenames from the previous step and even
     allows you to complete them with C-j]

You can replace C-x C-f with other similar commands, e.g., C-x b or M-x.
I’m not sure if this bug comes from how Icomplete configures itself or
the implementation of recursive minibuffers.  It appears that
icomplete-simple-completing-p returns t when the M-: is happening in a
recursive minibuffer, even though it should return nil so that Icomplete
doesn’t configure itself.

If the M-: is not in a recursive minibuffer, everything is OK since
icomplete-simple-completing-p returns nil.

Best regards,
Dario
  
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