Remote file name completion is also performed by auth-sources search

* doc/misc/tramp.texi (File name completion): User and host name
completion is also performed by auth-sources search.

* etc/NEWS: Document remote file name completion using auth-sources.

* lisp/net/tramp.el (tramp-completion-use-auth-sources):
New user option.
(tramp-parse-auth-sources): New defun.
(tramp-get-completion-function): Call it.

3 files changed, 32 insertions, 0 deletions

diff --git a/doc/misc/tramp.texi b/doc/misc/tramp.texi
index 128501c3908..f68205519f3 100644
--- a/doc/misc/tramp.texi
+++ b/doc/misc/tramp.texi
@@ -2538,6 +2538,14 @@ names on that host.
 When the configuration (@pxref{Customizing Completion}) includes user
 names, then the completion lists will account for the user names as well.
 
+@vindex tramp-completion-use-auth-sources
+Results from @code{auth-sources} search (@pxref{Using an
+authentication file}) are added to the completion candidates.  This
+search could be annoying, for example due to a passphrase request of
+the @file{~/.authinfo.gpg} authentication file.  The user option
+@code{tramp-completion-use-auth-sources} controls, whether such a
+search is performed during completion.
+
 Remote hosts previously visited or hosts whose connections are kept
 persistently (@pxref{Connection caching}) will be included in the
 completion lists.
diff --git a/etc/NEWS b/etc/NEWS
index 226ae1e1353..ac23b3b1814 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -751,6 +751,11 @@ are obsoleted in GVFS.
 *** Validated passwords are saved by auth-source backends which support this.
 
 +++
+*** During user and host name completion in the minibuffer, results
+from auth-source search are taken into account.  This can be disabled
+by setting user option 'tramp-completion-use-auth-sources' to nil.
+
++++
 *** The user option 'tramp-ignored-file-name-regexp' allows to disable
 Tramp for some look-alike remote file names.
 
diff --git a/lisp/net/tramp.el b/lisp/net/tramp.el
index a1246659d8d..13c3b5f939c 100644
--- a/lisp/net/tramp.el
+++ b/lisp/net/tramp.el
@@ -1985,6 +1985,8 @@ For definition of that list see `tramp-set-completion-function'."
   (append
    `(;; Default settings are taken into account.
      (tramp-parse-default-user-host ,method)
+     ;; Hits from auth-sources.
+     (tramp-parse-auth-sources ,method)
      ;; Hosts visited once shall be remembered.
      (tramp-parse-connection-properties ,method))
    ;; The method related defaults.
@@ -2788,6 +2790,23 @@ This function is added always in `tramp-get-completion-function'
 for all methods.  Resulting data are derived from default settings."
   `((,(tramp-find-user method nil nil) ,(tramp-find-host method nil nil))))
 
+(defcustom tramp-completion-use-auth-sources auth-source-do-cache
+  "Whether to use `auth-source-search' for completion of user and host names.
+This could be disturbing, if it requires a password / passphrase,
+as for \"~/.authinfo.gpg\"."
+  :group 'tramp
+  :version "27.1"
+  :type 'boolean)
+
+(defun tramp-parse-auth-sources (method)
+  "Return a list of (user host) tuples allowed to access for METHOD.
+This function is added always in `tramp-get-completion-function'
+for all methods.  Resulting data are derived from default settings."
+  (and tramp-completion-use-auth-sources
+       (mapcar
+        (lambda (x) `(,(plist-get x :user) ,(plist-get x :host)))
+        (auth-source-search :port method :max most-positive-fixnum))))
+
 ;; Generic function.
 (defun tramp-parse-group (regexp match-level skip-regexp)
    "Return a (user host) tuple allowed to access.