Company deletes asterisks in Eshell Mode

[fehmud]

Hello,

Company deletes asterisks entered in Eshell Mode. This problem does not happen with Shell Mode.

To reproduce:

• emacs -Q
• (add-to-list 'load-path "/path/to/company")
• (require 'company)
• (global-company-mode)
• M-x eshell
• type an asterisk

Software:

• Company 0.8.7
• Emacs 24.4

Thanks for your assistance.

[dgutov]

Do you see the same behavior if you type M-x completion-at-point, without enabling company-mode?

I see a different thing happen: no asterisks disappear, but both company-mode and completion-at-point raise an error after asterisks. Like this:

Debugger entered--Lisp error: (wrong-type-argument stringp ("/adb:" "/bin/" "/boot/" "/cdrom/" "/dev/" "/etc/" "/fcp:" "/ftp:" "/git:" "/home/" "/initrd.img" "/initrd.img.old" "/krlogin:" "/ksu:" "/lib/" "/lib32/" "/lib64/" "/lost+found/" "/media/" "/mnt/" "/nc:" "/opt/" "/plink:" "/plinkx:" "/proc/" "/pscp:" "/psftp:" "/rcp:" "/remcp:" "/remsh:" "/root/" "/rsh:" "/rsync:" "/run/" "/sbin/" "/scp:" "/scpx:" "/smb:" "/srv/" "/ssh:" "/sshx:" "/su:" "/sudo:" "/sys/" "/telnet:" "/tmp/" "/usr/" "/var/" "/vmlinuz" "/vmlinuz.old"))
  file-name-directory(("/adb:" "/bin/" "/boot/" "/cdrom/" "/dev/" "/etc/" "/fcp:" "/ftp:" "/git:" "/home/" "/initrd.img" "/initrd.img.old" "/krlogin:" "/ksu:" "/lib/" "/lib32/" "/lib64/" "/lost+found/" "/media/" "/mnt/" "/nc:" "/opt/" "/plink:" "/plinkx:" "/proc/" "/pscp:" "/psftp:" "/rcp:" "/remcp:" "/remsh:" "/root/" "/rsh:" "/rsync:" "/run/" "/sbin/" "/scp:" "/scpx:" "/smb:" "/srv/" "/ssh:" "/sshx:" "/su:" "/sudo:" "/sys/" "/telnet:" "/tmp/" "/usr/" "/var/" "/vmlinuz" "/vmlinuz.old"))
  eshell-complete-commands-list()
  #[0 "\300 \207" [eshell-complete-commands-list] 1 "\n\n(fn)"]()
  pcomplete--here(#[0 "\300 \207" [eshell-complete-commands-list] 1 "\n\n(fn)"] nil nil nil)
  #[0 "\300\301\302\211\211$\207" [pcomplete--here #[0 "\300 \207" [eshell-complete-commands-list] 1 "\n\n(fn)"] nil] 5 "\n\n(fn)"]()
  #[0 "\306�!\2053
...

I guess it gets interpreted as file path, and file paths disallow unescaped asterisks (..?).

[fehmud]

Thanks for your quick reply.

No errors here. Yes, M-x completion-at-point deletes the asterisk, but here it shows a completion window. Or, if I type a prefix that is long enough to have only one possible completion, and I append an asterisk, the successful completion deletes the asterisk. Therefore, it seems that this problem is caused by company-mode relying on completion-at-point.

[fehmud]

But -- also -- completion-at-point is meant to be called on-demand, therefore users can choose whether to trigger the completion of wildcards or not. On the other hand, Company always calls completion-at-point automatically, and users are left with no choice. Maybe Company should not be enabled by default in shells?

[dgutov]

Yes, M-x completion-at-point does that, but here it shows a completion window.

Okay, I can reproduce that now, in a bare Emacs session. Will have to see what customization of mine makes that behavior different.

completion-at-point is meant to be called on-demand, therefore users can choose whether to trigger the completion of wildcards or not.

Still, I see no possible benefit in replacing * with nothing. What might that mean in completion terms?

completion-at-point also adds a space, like I have pointed out in another issue.

Can you describe the exact sequence of commands (and the context) that makes it do that (in a comment, in the other issue)? That's the one thing I haven't been able to reproduce (specifically, with completion-at-point and directory paths in eshell).

[fehmud]

Still, I see no possible benefit in replacing * with nothing. What might that mean in completion terms?

It means that the entire pattern with wildcards will eventually be replaced with the full completion.

Without Company, M-x completion-at-point deletes the wildcard but then shows a list of completions that match the pattern with wildcards that the user has entered. If only one completion is possible, completion-at-point inserts it directly and echoes Sole completion. However -- at least in Eshell Mode -- completion-at-point seems buggy because if the pattern has some characters before the asterisk, then the asterisk gets deleted but no completion is shown.

Can you describe the exact sequence of commands (and the context) that makes it do that (in a comment, in the other issue)? That's the one thing I haven't been able to reproduce (specifically, with completion-at-point and directory paths in eshell).

I have noticed that Eshell Mode binds TAB to eshell-pcomplete instead of completion-at-point (like Shell Mode does), and eshell-pcomplete does not insert an extra space. Anyway, to reproduce the problem of the extra space with completion-at-point (Emacs 24.4 on GNU/Linux):

• emacs -Q
• M-x eshell
• type * in the Eshell buffer, followed by M-x completion-at-point
• select a completion

Thanks for your assistance.

[fehmud]

Anyway, both completion-at-point and eshell-pcomplete don't seem suitable for Company, because they have the side effect of changing the content of the buffer, and doing so automatically confuses the user.

Maybe Company could provide an option to exclude some major modes when calling global-company-mode, and by default such option would include shell modes.

[dgutov]

It means that the entire pattern with wildcards will eventually be replaced with the full completion.

But that doesn't happen with any other prefix, even though they would also be "eventually replaced".

So, http://debbugs.gnu.org/cgi/bugreport.cgi?bug=18951. Let's wait for the response.

And BTW, my original problem was http://debbugs.gnu.org/cgi/bugreport.cgi?bug=18950.

[shlomiv]

I experience the same thing, asterisks gets deleted in eshell when company-mode is enabled.

It has been some time since anything happened in this issue, any fixes or workarounds?

[quigonjeff]

I'm using spacemacs, and I have the same problem. Any solution or workaround?

[dgutov]

@quigonjeff None that I'm aware of. You might be better off commenting on the Emacs bug report directly.

[dakra]

I commented on the Emacs bug report and got a potential fix.

If someone wants to test it, just eval:

(defun pcomplete-parse-arguments (&optional expand-p)
  "Parse the command line arguments.  Most completions need this info."
  (let ((results (funcall pcomplete-parse-arguments-function)))
    (when results
      (setq pcomplete-args (or (car results) (list ""))
	    pcomplete-begins (or (cdr results) (list (point)))
	    pcomplete-last (1- (length pcomplete-args))
	    pcomplete-index 0
	    pcomplete-stub (pcomplete-arg 'last))
      (let ((begin (pcomplete-begin 'last)))
	(if (and (listp pcomplete-stub) ;??
		 (not pcomplete-expand-only-p))
	    (let* ((completions pcomplete-stub) ;??
		   (common-stub (car completions))
		   (c completions)
		   (len (length common-stub)))
	      (while (and c (> len 0))
		(while (and (> len 0)
			    (not (string=
				  (substring common-stub 0 len)
				  (substring (car c) 0
					     (min (length (car c))
						  len)))))
		  (setq len (1- len)))
		(setq c (cdr c)))
	      (setq pcomplete-stub (substring common-stub 0 len)
		    pcomplete-autolist t)
	      (when (and begin (> len 0) (not pcomplete-show-list))
		(delete-region begin (point))
		(pcomplete-insert-entry "" pcomplete-stub))
	      (throw 'pcomplete-completions completions))
	  (when expand-p
	    (if (stringp pcomplete-stub)
		(when begin
		  (delete-region begin (point))
		  (insert-and-inherit pcomplete-stub))
	      (if (and (listp pcomplete-stub)
		       pcomplete-expand-only-p)
		  ;; this is for the benefit of `pcomplete-expand'
		  (setq pcomplete-last-completion-length (- (point) begin)
			pcomplete-current-completions pcomplete-stub)
		(error "Cannot expand argument"))))
	  (if pcomplete-expand-only-p
	      (throw 'pcompleted t)
	    pcomplete-args))))))

and see if it fixes the problem and/or breaks something else.

[gopar]

@dakra tested snippet out. Can confirm it works \o/

[dakra]

@gopar nice.
jFYI, the fix is already included in Emacs26+ which is just around the corner :)