Re: Completion bug in gud or comint

[Lluís <xscript@gmx.net>]

Stefan Monnier writes:

>> I didn't find any related bug report, but I'm not sure if this has
>> been reported before in this list.

>> Steps to reproduce it:

>> M-x gdb
>> gdb -i=mi<RET>
>>>> (gdb) _
>> s<TAB>
>>>> (gdb) s_
>>>> <completion buffer output>
>> o<TAB>
>>>> source_
>> <TAB>
>>>> (gdb) _source

>> As you can see, the comint prompt ('(gdb)') "disappears" (already
>> strange enough) and the point moves accordingly when there is a common
>> completion prefix available, but performing a new completion makes the
>> prompt "reappear".

> I can't reproduce it with Emacs's trunk, starting as "emacs -Q".
> Have you tried your recipe with "emacs -Q"?

Yes.

I've also tried to `eval-buffer' comint, gud and gdb-mi from the latest trunk,
and the later (gdb-mi) hangs forever.

Just in case, I also tried to build a complete emacs from trunk and this is the
backtrace on quit when completing in the gud buffer:

Debugger entered--Lisp error: (quit)
  accept-process-output(#<process gud>)
  gud-gdb-run-command-fetch-lines("complete s" #<buffer *gud*> 0)
  gud-gdb-completions("" "s")
  apply(gud-gdb-completions "" "s")
  (closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args))("s")
  #[771 "\211\242\301=\206\n\211\302=?\205+r\303 \304!\203\0\305!\202\0p\262q\210\306\300!\x05$)\207" [(closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args)) boundaries metadata minibuffer-selected-window window-live-p window-buffer complete-with-action] 8 "\n\n(fn STRING PRED ACTION)"]("s" nil lambda)
  test-completion("s" #[771 "\211\242\301=\206\n\211\302=?\205+r\303 \304!\203\0\305!\202\0p\262q\210\306\300!\x05$)\207" [(closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args)) boundaries metadata minibuffer-selected-window window-live-p window-buffer complete-with-action] 8 "\n\n(fn STRING PRED ACTION)"] nil)
  completion--do-completion()
  minibuffer-complete()
  call-interactively(minibuffer-complete)
  #[1028 "\x01\304\x06\x06\305\211\306%\x18\305\262\x02\305\262\307\310\311#\210\n\203,\312\313!\210p\a\a\aF\314\315\316\317\320\321\x06!\322\"\323\324%DC\216\325\326!+\207" [minibuffer-completion-predicate minibuffer-completion-table completion-in-region-mode-predicate completion-in-region--data make-overlay nil t overlay-put field completion completion-in-region-mode 1 funcall make-byte-code 0 "\301\300!\207" vconcat vector [delete-overlay] 2 "\n\n(fn)" call-interactively minibuffer-complete] 14 "\n\n(fn START END COLLECTION PREDICATE)"](506 507 #[771 "\211\242\301=\206\n\211\302=?\205+r\303 \304!\203\0\305!\202\0p\262q\210\306\300!\x05$)\207" [(closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args)) boundaries metadata minibuffer-selected-window window-live-p window-buffer complete-with-action] 8 "\n\n(fn STRING PRED ACTION)"] nil)
  apply(#[1028 "\x01\304\x06\x06\305\211\306%\x18\305\262\x02\305\262\307\310\311#\210\n\203,\312\313!\210p\a\a\aF\314\315\316\317\320\321\x06!\322\"\323\324%DC\216\325\326!+\207" [minibuffer-completion-predicate minibuffer-completion-table completion-in-region-mode-predicate completion-in-region--data make-overlay nil t overlay-put field completion completion-in-region-mode 1 funcall make-byte-code 0 "\301\300!\207" vconcat vector [delete-overlay] 2 "\n\n(fn)" call-interactively minibuffer-complete] 14 "\n\n(fn START END COLLECTION PREDICATE)"] (506 507 #[771 "\211\242\301=\206\n\211\302=?\205+r\303 \304!\203\0\305!\202\0p\262q\210\306\300!\x05$)\207" [(closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args)) boundaries metadata minibuffer-selected-window window-live-p window-buffer complete-with-action] 8 "\n\n(fn STRING PRED ACTION)"] nil))
  #[771 ":\2030\x02@\301=\203\0\300@\302\x05A\"\303#\207\304@\305\306\307\310\311\312\300!\313\"\314\315%\x06A\x06##\207\304\316\"\207" [(#0) t append nil apply apply-partially make-byte-code 642 "\300@\x03#\207" vconcat vector [] 7 "\n\n(fn FUNS GLOBAL &rest ARGS)" #[1028 "\x01\304\x06\x06\305\211\306%\x18\305\262\x02\305\262\307\310\311#\210\n\203,\312\313!\210p\a\a\aF\314\315\316\317\320\321\x06!\322\"\323\324%DC\216\325\326!+\207" [minibuffer-completion-predicate minibuffer-completion-table completion-in-region-mode-predicate completion-in-region--data make-overlay nil t overlay-put field completion completion-in-region-mode 1 funcall make-byte-code 0 "\301\300!\207" vconcat vector [delete-overlay] 2 "\n\n(fn)" call-interactively minibuffer-complete] 14 "\n\n(fn START END COLLECTION PREDICATE)"]] 12 "\n\n(fn FUNS GLOBAL ARGS)"](nil nil (506 507 #[771 "\211\242\301=\206\n\211\302=?\205+r\303 \304!\203\0\305!\202\0p\262q\210\306\300!\x05$)\207" [(closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args)) boundaries metadata minibuffer-selected-window window-live-p window-buffer complete-with-action] 8 "\n\n(fn STRING PRED ACTION)"] nil))
  completion-in-region(506 507 #[771 "\211\242\301=\206\n\211\302=?\205+r\303 \304!\203\0\305!\202\0p\262q\210\306\300!\x05$)\207" [(closure (t) (&rest args) (apply (quote gud-gdb-completions) (quote "") args)) boundaries metadata minibuffer-selected-window window-live-p window-buffer complete-with-action] 8 "\n\n(fn STRING PRED ACTION)"] nil)
  completion-at-point()
  call-interactively(completion-at-point nil nil)


Evaluating the expression '(gud-gdb-completions "" "s")' does work correctly.


Lluis

-- 
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