bug#39389: 27.0.60; A couple of bugs messing with minibuffer completion of /sudo::

[Michael Albinus <michael.albinus@gmx.de>]

[-- Attachment #1: Type: text/plain, Size: 1228 bytes --]

Jimmy Yuen Ho Wong <wyuenho@gmail.com> writes:

Hi,

> Ok I've found a way to reproduce bug 2 and 3 *without* `exec-path-from-shell`.
>
> 0. Get on macOS 10.14
> 1. Install [GPGTools](https://gpgtools.org/), this will put the `gpg`
> binary into `/usr/local/bin`
> 2. env -i /Applications/MacPorts/Emacs.app/Contents/MacOS/Emacs -l
> tramp --eval '(setq tramp-verbose 10 exec-path (cons "/usr/local/bin/"
> exec-path))' /sudo::
> 3. Now the minibuffer prompt will be stuck at Tramp: Sending Password.
> 4. C-g to quit. I've attached a backtrace and the logs in *Messages* for this.
> 5. The `exec-path` is now `("/usr/local/bin/" "."
> "/Applications/MacPorts/Emacs.app/Contents/MacOS/libexec"
> "/Applications/MacPorts/Emacs.app/Contents/MacOS/bin")`. It appears as
> long as `.` is part of the search paths and `gpg` can be found in any
> of the search paths, the prompt will get stuck.
> 6. Saving the credentials for `root@localhost` into `~/.authinfo.gpg`
> will work around this issue.

A relative entry like "." in `exec-path' could be a problem, if
`call-process' searches for the gpg command, and `default-directory' is
remote. Could you pls check whether the appended patch solves it for you?

Best regards, Michael.


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: Type: text/x-patch, Size: 547 bytes --]

diff --git a/lisp/tramp.el b/lisp/tramp.el
index 7e68b639..4c057703 100644
--- a/lisp/tramp.el
+++ b/lisp/tramp.el
@@ -4868,7 +4868,8 @@ verbosity of 6."
   "Read a password from user (compat function).
 Consults the auth-source package.
 Invokes `password-read' if available, `read-passwd' else."
-  (let* ((case-fold-search t)
+  (let* ((default-directory (tramp-compat-temporary-file-directory))
+	 (case-fold-search t)
 	 (key (tramp-make-tramp-file-name
 	       ;; In tramp-sh.el, we must use "password-vector" due to
 	       ;; multi-hop.