bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

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When we open a file with find-file, the minibuffer offers method, user
name and host name completion for remote files. That is, after typing
"C-x C-f /ss TAB" we're offered with the completions "ssh:", "sshfs:"
and "sshx:". Same for user name and host name.

In eshell, this feature does not exist. I would like if I could type
"cd /ss TAB" and could see the same offering of "ssh:", "sshfs:" and
"sshx:". Same for user name and host name.

The appended patch does this for me. I have no idea how good it fits
into the eshell machinery, for example whether there are problems with
the em-elecslash.el module. Comments welcome!

Disclaimer: The idea has appeared on
<https://emacs.stackexchange.com/questions/78479/can-eshell-provide-tramp-auto-completion>.

Best regards, Michael.


In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
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diff --git a/lisp/eshell/em-tramp.el b/lisp/eshell/em-tramp.el
index 94eb9797033..c90e689f6de 100644
--- a/lisp/eshell/em-tramp.el
+++ b/lisp/eshell/em-tramp.el
@@ -51,11 +51,23 @@ eshell-tramp-initialize
   "Initialize the Tramp-using commands code."
   (when (eshell-using-module 'eshell-cmpl)
     (add-hook 'pcomplete-try-first-hook
-	      'eshell-complete-host-reference nil t))
+              'eshell-complete-partial-tramp-file-name))
   (setq-local eshell-complex-commands
               (append '("su" "sudo" "doas")
                       eshell-complex-commands)))

+(defun eshell-complete-partial-tramp-file-name ()
+  "Complete a partial Tramp file name (method, user name, hostname)."
+  (let ((arg (pcomplete-actual-arg))
+        (non-essential t)
+        (minibuffer-completing-file-name t))
+    (when (string-match tramp-completion-file-name-regexp arg)
+      (setq pcomplete-stub (substring arg (length tramp-prefix-format))
+            pcomplete-last-completion-raw t
+            pcomplete-termination-string "")
+      (throw 'pcomplete-completions
+             (file-name-all-completions pcomplete-stub tramp-prefix-format)))))
+
 (autoload 'eshell-parse-command "esh-cmd")

 (defun eshell/su (&rest args)

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Jim Porter]

X-Debbugs-Cc: monnier@iro.umontreal.ca

On 8/17/2023 11:01 AM, Michael Albinus wrote:
> In eshell, this feature does not exist. I would like if I could type
> "cd /ss TAB" and could see the same offering of "ssh:", "sshfs:" and
> "sshx:". Same for user name and host name.
> 
> The appended patch does this for me. I have no idea how good it fits
> into the eshell machinery, for example whether there are problems with
> the em-elecslash.el module. Comments welcome!

Thanks. This would be a useful feature indeed. I have a couple of main 
concerns, which I'm not quite sure what to do about at the moment:

1) Should this go in the Eshell Tramp extension module? Currently, that 
module is there to add built-in versions of su/sudo/doas, as an 
alternative to the "standard" Eshell way of connecting to a remote host: 
"cd /ssh:user@host:~". Therefore, I think we'd want tab-completion of 
Tramp file names even (or especially!) when the Tramp extension module 
is disabled (which is the default).

2) I'm not sure 'pcomplete-try-first-hook' is the right way to enable 
this. Pcomplete has quite a few ways of performing completions, and it 
already knows when it should specifically complete file names (as 
opposed to "--options" for example). Maybe we should enhance Pcomplete 
itself so that you can opt into completion of remote file names too? 
Then when you tab-complete in Eshell, it would just work in all the 
contexts where you can normally complete a file name. I Cc'ed Stefan 
since he might have some thoughts on the Pcomplete machinery here.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Jim Porter <jporterbugs@gmail.com> writes:

Hi Jim,

> X-Debbugs-Cc: monnier@iro.umontreal.ca

Well, this works only if you *submit* a new bug. If you *reply*, just
use Cc. I've added Stefan in this reply.

>> In eshell, this feature does not exist. I would like if I could type
>> "cd /ss TAB" and could see the same offering of "ssh:", "sshfs:" and
>> "sshx:". Same for user name and host name.
>>
>> The appended patch does this for me. I have no idea how good it fits
>> into the eshell machinery, for example whether there are problems with
>> the em-elecslash.el module. Comments welcome!
>
> Thanks. This would be a useful feature indeed. I have a couple of main
> concerns, which I'm not quite sure what to do about at the moment:
>
> 1) Should this go in the Eshell Tramp extension module? Currently,
> that module is there to add built-in versions of su/sudo/doas, as an
> alternative to the "standard" Eshell way of connecting to a remote
> host: "cd /ssh:user@host:~". Therefore, I think we'd want
> tab-completion of Tramp file names even (or especially!) when the
> Tramp extension module is disabled (which is the default).

I have no preference where it shall be in eshell. I've used em-tramp.el
during my work, because it is the least invasive place: it requires
already Tramp. You might have seen, that the new function uses two Tramp
variables.

> 2) I'm not sure 'pcomplete-try-first-hook' is the right way to enable
> this. Pcomplete has quite a few ways of performing completions, and it
> already knows when it should specifically complete file names (as
> opposed to "--options" for example). Maybe we should enhance Pcomplete
> itself so that you can opt into completion of remote file names too?
> Then when you tab-complete in Eshell, it would just work in all the
> contexts where you can normally complete a file name. I Cc'ed Stefan
> since he might have some thoughts on the Pcomplete machinery here.

When I've started to implement this, I was a n00b wrt pcomplete. Well,
I'm still a n00b, all what I have done is stealing code from somewhere
else, shamelessly.

It would be great if this completion function applies only to possible
*Lisp* file names. Roughly said, to arguments of commands not being
external, and not in a pipe. If this could be arranged I'd appreciate
it. So I count on you and Stefan :-)

Best regards, Michael.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Michael Albinus <michael.albinus@gmx.de> writes:

Hi Jim,

>> 2) I'm not sure 'pcomplete-try-first-hook' is the right way to enable
>> this. Pcomplete has quite a few ways of performing completions, and it
>> already knows when it should specifically complete file names (as
>> opposed to "--options" for example). Maybe we should enhance Pcomplete
>> itself so that you can opt into completion of remote file names too?
>> Then when you tab-complete in Eshell, it would just work in all the
>> contexts where you can normally complete a file name. I Cc'ed Stefan
>> since he might have some thoughts on the Pcomplete machinery here.
>
> When I've started to implement this, I was a n00b wrt pcomplete. Well,
> I'm still a n00b, all what I have done is stealing code from somewhere
> else, shamelessly.
>
> It would be great if this completion function applies only to possible
> *Lisp* file names. Roughly said, to arguments of commands not being
> external, and not in a pipe. If this could be arranged I'd appreciate
> it. So I count on you and Stefan :-)

I've digged further. Perhaps, we don't need to plug into eshell. It
could be sufficient to teach pcomplete.

First, we need a completion table for Tramp prefixes. Like

--8<---------------cut here---------------start------------->8---
(defun pcomplete-tramp ()
  "Completion table for partial Tramp file names."
  (completion-table-dynamic
   (lambda (string)
     (when (string-match-p tramp-completion-file-name-regexp string)
       (mapcar
	(lambda (x) (concat tramp-prefix-format x))
	(let ((non-essential t)
	      (minibuffer-completing-file-name t))
	  (file-name-all-completions string tramp-prefix-format)))))))
--8<---------------cut here---------------end--------------->8---

We could use this table to pimp up (existing) pcomplete functions for
builtin commands, like

--8<---------------cut here---------------start------------->8---
(defun pcomplete/cd ()
  "Completion for `cd'."
  (while (pcomplete-here (completion-table-in-turn
			  (pcomplete-tramp)
			  (pcomplete-dirs)))))
--8<---------------cut here---------------end--------------->8---

WDYT?

Best regards, Michael.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors]

> --8<---------------cut here---------------start------------->8---
> (defun pcomplete/cd ()
>   "Completion for `cd'."
>   (while (pcomplete-here (completion-table-in-turn
> 			  (pcomplete-tramp)
> 			  (pcomplete-dirs)))))
> --8<---------------cut here---------------end--------------->8---

AFIK this applies to `M-x shell` as well, so it doesn't seem
quite right.


        Stefan

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

Hi Stefan,

>> --8<---------------cut here---------------start------------->8---
>> (defun pcomplete/cd ()
>>   "Completion for `cd'."
>>   (while (pcomplete-here (completion-table-in-turn
>> 			  (pcomplete-tramp)
>> 			  (pcomplete-dirs)))))
>> --8<---------------cut here---------------end--------------->8---
>
> AFIK this applies to `M-x shell` as well, so it doesn't seem
> quite right.

Yes. However, there is already another problem in shell-mode. My patch
completes only incomplete Tramp file names, like "/ss". Complete Tramp
file names are handled by pcomplete-dirs already. So we see in a *shell*
buffer, w/o my patch:

--8<---------------cut here---------------start------------->8---
[albinus@gandalf ~]$ cd /ssh:host: TAB
=> all directories on that remote host
--8<---------------cut here---------------end--------------->8---

So we must fix completion of remote file names in shell-mode anyway. This
would prevent also the modified pcomplete/cd to show any Tramp related
file name.

>         Stefan

Best regards, Michael.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> --8<---------------cut here---------------start------------->8---
>> (defun pcomplete/cd ()
>>   "Completion for `cd'."
>>   (while (pcomplete-here (completion-table-in-turn
>> 			  (pcomplete-tramp)
>> 			  (pcomplete-dirs)))))
>> --8<---------------cut here---------------end--------------->8---
>
> AFIK this applies to `M-x shell` as well, so it doesn't seem
> quite right.

We might use a flag which determines, whether remote file name completion
is appropriate. In shell-mode remote file names shall be suppressed, and in
eshell-mode it should be set depending on the command. "cd" should
support remote file names, "*cd" should suppress them. Other packages
use pcomplete as well, like erc and org. Whether they need to handle
remote file names I don't know.

This flag should be checked in pcomplete-tramp, pcomplete-dirs and
whatever other pcomplete completion tables are concerned. This would fix
also the other (minor) bug I've uncovered in shell-mode in my last message.

There are already such flags, which control this kind of completion,
like pcomplete-file-ignore, pcomplete-dir-ignore, pcomplete-autolist,
you name it. What about a new boolean flag pcomplete-remote-ignore?

WDYT?

>         Stefan

Best regards, Michael.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors]

> Yes. However, there is already another problem in shell-mode. My patch
> completes only incomplete Tramp file names, like "/ss". Complete Tramp
> file names are handled by pcomplete-dirs already. So we see in a *shell*
> buffer, w/o my patch:

Good point.

Still, we have the problem that `pcomplete/<CMD>` should be used only
for external commands (because they are independent from the language
used to write the command, a.k.a the shell), but for things like `cd` we
should be more precise to distinguish the completion rules for Eshell's
`cd` from those of bash's `cd`.


        Stefan

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Jim Porter]

On 8/18/2023 3:33 PM, Stefan Monnier via Bug reports for GNU Emacs, the 
Swiss army knife of text editors wrote:
>> Yes. However, there is already another problem in shell-mode. My patch
>> completes only incomplete Tramp file names, like "/ss". Complete Tramp
>> file names are handled by pcomplete-dirs already. So we see in a *shell*
>> buffer, w/o my patch:
> 
> Good point.
> 
> Still, we have the problem that `pcomplete/<CMD>` should be used only
> for external commands (because they are independent from the language
> used to write the command, a.k.a the shell), but for things like `cd` we
> should be more precise to distinguish the completion rules for Eshell's
> `cd` from those of bash's `cd`.

That should be possible by defining 'pcomplete/eshell-mode/CMD', but 
that runs into two issues: 1) it's annoying to manually write all of 
these, and 2) there may be other contexts in Eshell we want to 
tab-complete remote directories that aren't covered by the 
command-specific Pcomplete functions like that.

(#1 should be fixable with a new version of 'eshell-eval-using-options', 
but I haven't looked at that in much detail yet.)

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

[-- Attachment #1: Type: text/plain, Size: 2113 bytes --]

Jim Porter <jporterbugs@gmail.com> writes:

Hi Jim & Stefan,

>>> Yes. However, there is already another problem in shell-mode. My patch
>>> completes only incomplete Tramp file names, like "/ss". Complete Tramp
>>> file names are handled by pcomplete-dirs already. So we see in a *shell*
>>> buffer, w/o my patch:
>> Good point.
>> Still, we have the problem that `pcomplete/<CMD>` should be used
>> only
>> for external commands (because they are independent from the language
>> used to write the command, a.k.a the shell), but for things like `cd` we
>> should be more precise to distinguish the completion rules for Eshell's
>> `cd` from those of bash's `cd`.
>
> That should be possible by defining 'pcomplete/eshell-mode/CMD', but
> that runs into two issues: 1) it's annoying to manually write all of
> these, and 2) there may be other contexts in Eshell we want to
> tab-complete remote directories that aren't covered by the
> command-specific Pcomplete functions like that.
>
> (#1 should be fixable with a new version of
> 'eshell-eval-using-options', but I haven't looked at that in much
> detail yet.)

I gave it another try. There is a new user option pcomplete-remote-ignore.
When nil (the default), pcomplete expands remote file names, including
method, user name and host name. The corresponding let-bindings in
pcomplete--entries are short.

In shell-completion-vars, I set it buffer-local to t. This prevents
remote file name completion in *shell* buffers, fixing also the bug
mentioned above.

In eshell I haven't set anything, so by default remote file names are
expanded. It should be easy to set pcomplete-remote-ignore, depending
on whether the command is a built-in (keep it nil), or an external
command (set it to t).

The patch is appended. Please note, that this has effect only when Tramp
is loaded, so you might need to test with "emacs -Q -l tramp". People,
who never use Tramp, won't see a difference.

For testing you need a recent checkout of Emacs master, because I have
added another function to tramp.el. This is already pushed to master.

Comments?

Best regards, Michael.


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: Type: text/x-patch, Size: 1819 bytes --]

diff --git a/lisp/pcomplete.el b/lisp/pcomplete.el
index c7ec228c1db..e8bede9d605 100644
--- a/lisp/pcomplete.el
+++ b/lisp/pcomplete.el
@@ -138,6 +138,11 @@ pcomplete-dir-ignore
   "A regexp of names to be disregarded during directory completion."
   :type '(choice regexp (const :tag "None" nil)))

+(defcustom pcomplete-remote-ignore nil
+  "Whether to ignore remote file names."
+  :version "30.1"
+  :type 'boolean)
+
 (define-obsolete-variable-alias 'pcomplete-ignore-case 'completion-ignore-case
   "28.1")

@@ -924,7 +929,10 @@ pcomplete--entries
                            (sort comps pcomplete-compare-entry-function)))
                      ,@(cdr (completion-file-name-table s p a)))
         (let ((completion-ignored-extensions nil)
-	      (completion-ignore-case completion-ignore-case))
+	      (completion-ignore-case completion-ignore-case)
+              (tramp-mode (and tramp-mode (not pcomplete-remote-ignore)))
+              (non-essential (not (file-remote-p s)))
+              (minibuffer-completing-file-name  (not (file-remote-p s))))
           (completion-table-with-predicate
            #'comint-completion-file-name-table pred 'strict s p a))))))

diff --git a/lisp/shell.el b/lisp/shell.el
index 7ea9d1c2ead..17ab12dda6d 100644
--- a/lisp/shell.el
+++ b/lisp/shell.el
@@ -595,6 +595,8 @@ shell-completion-vars
   ;; Don't use pcomplete's defaulting mechanism, rely on
   ;; shell-dynamic-complete-functions instead.
   (setq-local pcomplete-default-completion-function #'ignore)
+  ;; Do not expand remote file names.
+  (setq-local pcomplete-remote-ignore t)
   (setq-local comint-input-autoexpand shell-input-autoexpand)
   ;; Not needed in shell-mode because it's inherited from comint-mode, but
   ;; placed here for read-shell-command.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors]

> I gave it another try. There is a new user option pcomplete-remote-ignore.

FWIW, `pcomplete` is a generic completion library for use when
completing things like function/command calls where the things to be
completely at point depend on the position of the argument and the
command/function that is called.

It was originally designed for Eshell where those functions/commands are
actual commands in the host system, but it's also used for things like
ERC where the commands have nothing to do with executables installed in
your machine.

In theory is could be used for completion in code buffers where it
could provide specialized completion depending on the expected type of
the argument being completed.


        Stefan

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

Hi Stefan,

>> I gave it another try. There is a new user option pcomplete-remote-ignore.
>
> FWIW, `pcomplete` is a generic completion library for use when
> completing things like function/command calls where the things to be
> completely at point depend on the position of the argument and the
> command/function that is called.
>
> It was originally designed for Eshell where those functions/commands are
> actual commands in the host system, but it's also used for things like
> ERC where the commands have nothing to do with executables installed in
> your machine.

ERC should could set pcomplete-remote-ignore to t, as I have proposed
for shell buffers. Likely, even this isn't needed. The default (w/o my
patch) is to complete remote file names. This hasn't disturbed ERC until
now.

> In theory is could be used for completion in code buffers where it
> could provide specialized completion depending on the expected type of
> the argument being completed.

Hmm. Does it mean you agree with the patch, or not? My change should affect
only file name completion, any other completion should work as before.

>         Stefan

Best regards, Michael.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Stefan Monnier via Bug reports for GNU Emacs, the Swiss army knife of text editors]

> ERC should could set pcomplete-remote-ignore to t, as I have proposed

Not sure if ERC's pcomplete ever completes file names, to be honest.

>> In theory is could be used for completion in code buffers where it
>> could provide specialized completion depending on the expected type of
>> the argument being completed.
> Hmm.  Does it mean you agree with the patch, or not?  My change should
> affect only file name completion, any other completion should work
> as before.

Yes, it's OK.  I was just pointing out that pcomplete doesn't
specifically have anything to do with (completion of) file names, so the
new variable is not really relevant to "pcomplete proper" but only to
the set of defaults that are provided along with pcomplete.
The name might try and reflect that a bit more, e.g. by including
"file" somewhere.


        Stefan

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Jim Porter]

On 8/19/2023 10:48 AM, Michael Albinus wrote:
> The patch is appended. Please note, that this has effect only when Tramp
> is loaded, so you might need to test with "emacs -Q -l tramp". People,
> who never use Tramp, won't see a difference.
> 
> For testing you need a recent checkout of Emacs master, because I have
> added another function to tramp.el. This is already pushed to master.
> 
> Comments?

This works for me, and I think it makes sense overall. It might be nice 
to add the ability to ignore remote file names in Eshell when completing 
an argument to an external command (which doesn't understand Tramp 
syntax), but that would probably require a bunch of work on the Eshell 
side, and we can worry about that later, I think.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

Hi Stefan,

> Yes, it's OK.  I was just pointing out that pcomplete doesn't
> specifically have anything to do with (completion of) file names, so the
> new variable is not really relevant to "pcomplete proper" but only to
> the set of defaults that are provided along with pcomplete.
> The name might try and reflect that a bit more, e.g. by including
> "file" somewhere.

I've pushed it to master. The user option is called now
pcomplete-remote-file-ignore.

>         Stefan

Best regards, Michael.

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

[-- Attachment #1: Type: text/plain, Size: 649 bytes --]

Jim Porter <jporterbugs@gmail.com> writes:

Hi Jim,

> This works for me, and I think it makes sense overall. It might be
> nice to add the ability to ignore remote file names in Eshell when
> completing an argument to an external command (which doesn't
> understand Tramp syntax), but that would probably require a bunch of
> work on the Eshell side, and we can worry about that later, I think.

As POC, I've written the appended patch. It works for me in a simple
case, but I'm pretty sure it needs to handle more cases. Since I'm not
so familiar with Eshell, I let it to you :-)

... unless you say it is sufficient ATM.

Best regards, Michael.


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: Type: text/x-patch, Size: 2518 bytes --]

diff --git a/lisp/eshell/em-cmpl.el b/lisp/eshell/em-cmpl.el
index 732bbb3f1fa..25dccbd695c 100644
--- a/lisp/eshell/em-cmpl.el
+++ b/lisp/eshell/em-cmpl.el
@@ -148,6 +148,10 @@ eshell-cmpl-dir-ignore
   (eshell-cmpl--custom-variable-docstring 'pcomplete-dir-ignore)
   :type (get 'pcomplete-dir-ignore 'custom-type))

+(defcustom eshell-cmpl-remote-file-ignore nil
+  (eshell-cmpl--custom-variable-docstring 'pcomplete-remote-file-ignore)
+  :type (get 'pcomplete-remote-file-ignore 'custom-type))
+
 (defcustom eshell-cmpl-ignore-case (eshell-under-windows-p)
   (eshell-cmpl--custom-variable-docstring 'completion-ignore-case)
   :type (get 'completion-ignore-case 'custom-type))
@@ -248,6 +252,8 @@ eshell-cmpl-initialize
               eshell-cmpl-file-ignore)
   (setq-local pcomplete-dir-ignore
               eshell-cmpl-dir-ignore)
+  (setq-local pcomplete-remote-file-ignore
+              eshell-cmpl-remote-file-ignore)
   (setq-local completion-ignore-case
               eshell-cmpl-ignore-case)
   (setq-local pcomplete-autolist
@@ -325,6 +331,15 @@ eshell-complete--eval-argument-form
             "Failed to evaluate argument form during completion: %S" arg)
      (propertize "\0" 'eshell-argument-stub 'error))))

+;; Code stolen from `eshell-plain-command'.
+(defun eshell-external-command-p (command)
+  "Whether an external command shall be called."
+  (let* ((esym (eshell-find-alias-function command))
+	 (sym (or esym (intern-soft command))))
+    (not (and sym (fboundp sym)
+	      (or esym eshell-prefer-lisp-functions
+		  (not (eshell-search-path command)))))))
+
 (defun eshell-complete-parse-arguments ()
   "Parse the command line arguments for `pcomplete-argument'."
   (when (and eshell-no-completion-during-jobs
@@ -406,6 +421,14 @@ eshell-complete-parse-arguments
        args posns)
       (setq args (nreverse evaled-args)
             posns (nreverse evaled-posns)))
+    ;; Determine, whether remote file names shall be completed.  They
+    ;; shouldn't for external commands, or when in a pipe.  Respect
+    ;; also `eshell-cmpl-remote-file-ignore', which could be set by
+    ;; the user.
+    (setq-local pcomplete-remote-file-ignore
+                (or eshell-cmpl-remote-file-ignore
+                    eshell-in-pipeline-p ; does not work
+                    (eshell-external-command-p (car args))))
     ;; Convert arguments to forms that Pcomplete can understand.
     (cons (mapcar
            (lambda (arg)

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Jim Porter]

On 8/20/2023 3:53 AM, Michael Albinus wrote:
> As POC, I've written the appended patch. It works for me in a simple
> case, but I'm pretty sure it needs to handle more cases. Since I'm not
> so familiar with Eshell, I let it to you :-)
> 
> ... unless you say it is sufficient ATM.

Let's just go with the change to add 'pcomplete-remote-file-ignore' for 
now. I'll have to think more about how Eshell can selectively ignore 
remote files correctly in all cases; there are a bunch of areas where 
Eshell could be smarter about completion already, and I have the feeling 
they'll conflict with each other if we don't plan this out carefully...

bug#65356: 30.0.50; [wishlist] Support Tramp method, user name and host name completion in eshell

[Michael Albinus]

Version: 30.1

Jim Porter <jporterbugs@gmail.com> writes:

Hi Jim,

> Let's just go with the change to add 'pcomplete-remote-file-ignore'
> for now. I'll have to think more about how Eshell can selectively
> ignore remote files correctly in all cases; there are a bunch of areas
> where Eshell could be smarter about completion already, and I have the
> feeling they'll conflict with each other if we don't plan this out
> carefully...

Agreed. Pushed to master, I'm closing the bug.

Best regards, Michael.