master 9d48c9844bf 3/3: Don't add a space after the trailing slash when completing ~USER in Eshell

[Jim Porter]

branch: master
commit 9d48c9844bf6b27fede6fe8f864e6dfb6909586b
Author: Jim Porter <jporterbugs@gmail.com>
Commit: Jim Porter <jporterbugs@gmail.com>

    Don't add a space after the trailing slash when completing ~USER in Eshell
    
    This provides a programmed completion function that works similarly to
    ~USER completion in 'completion-file-name-table'.
    
    * lisp/eshell/em-dirs.el (eshell-complete-user-reference): Throw a
    programmed completion function.
    
    * test/lisp/eshell/em-cmpl-tests.el
    (em-cmpl-test/user-ref-completion): Update test.
---
 lisp/eshell/em-dirs.el            | 37 ++++++++++++++++++++++++++++---------
 test/lisp/eshell/em-cmpl-tests.el |  5 ++---
 2 files changed, 30 insertions(+), 12 deletions(-)

diff --git a/lisp/eshell/em-dirs.el b/lisp/eshell/em-dirs.el
index 0d02b64b084..62d37e8f9fe 100644
--- a/lisp/eshell/em-dirs.el
+++ b/lisp/eshell/em-dirs.el
@@ -281,15 +281,34 @@ Thus, this does not include the current directory.")
   (let ((arg (pcomplete-actual-arg)))
     (when (string-match "\\`~[a-z]*\\'" arg)
       (setq pcomplete-stub (substring arg 1)
-           pcomplete-last-completion-raw t)
-      (throw 'pcomplete-completions
-            (progn
-              (eshell-read-user-names)
-              (pcomplete-uniquify-list
-               (mapcar
-                 (lambda (user)
-                   (file-name-as-directory (cdr user)))
-                eshell-user-names)))))))
+            pcomplete-last-completion-raw t)
+            ;; pcomplete-exit-function #'eshell-complete-user-ref--exit)
+      (eshell-read-user-names)
+      (let ((names (pcomplete-uniquify-list
+                    (mapcar (lambda (user)
+                              (file-name-as-directory (cdr user)))
+                            eshell-user-names))))
+        (throw 'pcomplete-completions
+               ;; Provide a programmed completion table.  This works
+               ;; just like completing over the list of names, except
+               ;; it always returns the completed string, never `t'.
+               ;; That's because this is only completing a directory
+               ;; name, and so the completion isn't actually finished
+               ;; yet.
+               (lambda (string pred action)
+                 (pcase action
+                   ('nil                  ; try-completion
+                    (let ((result (try-completion string names pred)))
+                      (if (eq result t) string result)))
+                   ('t                    ; all-completions
+                    (all-completions string names pred))
+                   ('lambda               ; test-completion
+                     (let ((result (test-completion string names pred)))
+                       (if (eq result t) string result)))
+                   ('metadata
+                    '(metadata (category . file)))
+                   (`(boundaries . ,suffix)
+                    `(boundaries 0 . ,(string-search "/" suffix))))))))))
 
 (defun eshell/pwd (&rest _args)
   "Change output from `pwd' to be cleaner."
diff --git a/test/lisp/eshell/em-cmpl-tests.el 
b/test/lisp/eshell/em-cmpl-tests.el
index 1f8c571c44c..ecab7332822 100644
--- a/test/lisp/eshell/em-cmpl-tests.el
+++ b/test/lisp/eshell/em-cmpl-tests.el
@@ -218,15 +218,14 @@ See <lisp/eshell/esh-var.el>."
                     "VAR=file.txt ")))))
 
 (ert-deftest em-cmpl-test/user-ref-completion ()
-  "Test completeion of user references like \"~user\".
+  "Test completion of user references like \"~user\".
 See <lisp/eshell/em-dirs.el>."
   (unwind-protect
       (with-temp-eshell
        (cl-letf (((symbol-function 'eshell-read-user-names)
                   (lambda () (setq eshell-user-names '((1234 . "user"))))))
-         ;; FIXME: Should this really add a space at the end?
          (should (equal (eshell-insert-and-complete "echo ~us")
-                        "echo ~user/ "))))
+                        "echo ~user/"))))
     ;; Clear the cached user names we set above.
     (setq eshell-user-names nil)))