emacs: Add a space after completed tag operations

Previously, when a user fully completed a tag operation, they had to
press space to begin entering another tag operation.  This is
different from, say, shell file name completion, which typically
inserts a space after an unambiguous completion under the assumption
that the user will want to enter more input.

This patch tweaks `notmuch-read-tag-changes' to act more like shell
file name completion: after an unambiguous tag completion, it now
inserts a space, ready and waiting for another tagging operation from
the user.  This is backwards-compatible with old habits, since there's
no harm in putting an extra space.

1 files changed, 10 insertions, 2 deletions

diff --git a/emacs/notmuch-tag.el b/emacs/notmuch-tag.el
index 22a603fc..f705ac5d 100644
--- a/emacs/notmuch-tag.el
+++ b/emacs/notmuch-tag.el
@@ -230,8 +230,16 @@ initial input in the minibuffer."
 	    (set-keymap-parent map crm-local-completion-map)
 	    (define-key map " " 'self-insert-command)
 	    map)))
-    (delete "" (completing-read-multiple prompt
-		tag-list nil nil initial-input
+    (delete "" (completing-read-multiple
+		prompt
+		;; Append the separator to each completion so when the
+		;; user completes a tag they can immediately begin
+		;; entering another.  `completing-read-multiple'
+		;; ultimately splits the input on crm-separator, so we
+		;; don't need to strip this back off (we just need to
+		;; delete "empty" entries caused by trailing spaces).
+		(mapcar (lambda (tag-op) (concat tag-op crm-separator)) tag-list)
+		nil nil initial-input
 		'notmuch-read-tag-changes-history))))
 
 (defun notmuch-update-tags (tags tag-changes)