Trim titles in eww so that the host from the URL is visible

* lisp/net/eww.el (eww-update-header-line-format): Trim the line
of the title so that the host bit of the URL is visible (bug#42898).

diff --git a/lisp/net/eww.el b/lisp/net/eww.el
index e7170b3e6d1c2ce8eeeaa44378b79a074b77fb78..04deb5bee056c4c13e5ea2379634046b3ca551f1 100644 (file)
--- a/lisp/net/eww.el
+++ b/lisp/net/eww.el
@@ -672,9 +672,30 @@ Currently this means either text/html or application/xhtml+xml."
   (setq header-line-format
        (and eww-header-line-format
             (let ((title (plist-get eww-data :title))
-                  (peer (plist-get eww-data :peer)))
+                  (peer (plist-get eww-data :peer))
+                   (url (plist-get eww-data :url)))
               (when (zerop (length title))
                 (setq title "[untitled]"))
+               ;; Limit the length of the title so that the host name
+               ;; of the URL is always visible.
+               (when url
+                 (let* ((parsed (url-generic-parse-url url))
+                        (host-length (length (format "%s://%s"
+                                                     (url-type parsed)
+                                                     (url-host parsed))))
+                        (width (window-width)))
+                   (cond
+                    ;; The host bit is wider than the window, so nix
+                    ;; the title.
+                    ((> (+ host-length 5) width)
+                     (setq title ""))
+                    ;; Trim the title.
+                    ((> (+ (length title) host-length 2) width)
+                     (setq title (concat
+                                  (substring title 0 (- width
+                                                        host-length
+                                                        5))
+                                  "..."))))))
               ;; This connection has is https.
               (when peer
                 (setq title
@@ -686,7 +707,7 @@ Currently this means either text/html or application/xhtml+xml."
                "%" "%%"
                (format-spec
                 eww-header-line-format
-                `((?u . ,(or (plist-get eww-data :url) ""))
+                `((?u . ,(or url ""))
                   (?t . ,title))))))))
 
 (defun eww-tag-title (dom)