gnu: emacs-magit: Add patch for compatibility with emacs-forge.

* gnu/local.mk (emacs-magit-format-author-margin.patch): Add patch.
* gnu/packages/emacs-xyz.scm: Add.
* gnu/packages/patches/emacs-magit-log-format-author-margin.patch: Add.

3 files changed, 78 insertions, 0 deletions

diff --git a/gnu/local.mk b/gnu/local.mk
index 6ec1bbf2e4..ba8cc1ee1f 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -794,6 +794,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/emacs-fix-scheme-indent-function.patch	\
   %D%/packages/patches/emacs-json-reformat-fix-tests.patch	\
   %D%/packages/patches/emacs-highlight-stages-add-gexp.patch	\
+  %D%/packages/patches/emacs-magit-log-format-author-margin.patch	\
   %D%/packages/patches/emacs-scheme-complete-scheme-r5rs-info.patch	\
   %D%/packages/patches/emacs-source-date-epoch.patch		\
   %D%/packages/patches/emacs-undohist-ignored.patch	\
diff --git a/gnu/packages/emacs-xyz.scm b/gnu/packages/emacs-xyz.scm
index 3d8aafd3e6..ddaaa01727 100644
--- a/gnu/packages/emacs-xyz.scm
+++ b/gnu/packages/emacs-xyz.scm
@@ -281,6 +281,11 @@ on stdout instead of using a socket as the Emacsclient does.")
                 (sha256
                  (base32
                   "16qx0404l05q1m6w7y5j8ck1z5nfmpinm00w0p2yh1hn5zzwy6dd"))
+                ;; FIXME: emacs-forge uses a function defined in this patch,
+                ;; which is newer than the current commit.
+                (patches
+                 (search-patches
+                  "emacs-magit-log-format-author-margin.patch"))
                 (modules '((guix build utils)))
                 (snippet
                  '(begin
diff --git a/gnu/packages/patches/emacs-magit-log-format-author-margin.patch b/gnu/packages/patches/emacs-magit-log-format-author-margin.patch
new file mode 100644
index 0000000000..fc52157a32
--- /dev/null
+++ b/gnu/packages/patches/emacs-magit-log-format-author-margin.patch
@@ -0,0 +1,72 @@
+From 94914ca4690c0cff12d600a0c8ba6bfb3fb38dc5 Mon Sep 17 00:00:00 2001
+From: Jonas Bernoulli <jonas@bernoul.li>
+Date: Tue, 25 Jun 2019 21:44:32 +0200
+Subject: [PATCH] magit-log-format-author-margin: New function
+
+Split it from `magit-log-format-margin'.
+---
+ lisp/magit-log.el | 48 +++++++++++++++++++++++++----------------------
+ 1 file changed, 26 insertions(+), 22 deletions(-)
+
+diff --git a/lisp/magit-log.el b/lisp/magit-log.el
+index c8e6ef63..c0a79b19 100644
+--- a/lisp/magit-log.el
++++ b/lisp/magit-log.el
+@@ -1374,28 +1374,32 @@ The shortstat style is experimental and rather slow."
+   (when-let ((option (magit-margin-option)))
+     (if magit-log-margin-show-shortstat
+         (magit-log-format-shortstat-margin rev)
+-      (pcase-let ((`(,_ ,style ,width ,details ,details-width)
+-                   (or magit-buffer-margin
+-                       (symbol-value option))))
+-        (magit-make-margin-overlay
+-         (concat (and details
+-                      (concat (propertize (truncate-string-to-width
+-                                           (or author "")
+-                                           details-width
+-                                           nil ?\s (make-string 1 magit-ellipsis))
+-                                          'face 'magit-log-author)
+-                              " "))
+-                 (propertize
+-                  (if (stringp style)
+-                      (format-time-string
+-                       style
+-                       (seconds-to-time (string-to-number date)))
+-                    (pcase-let* ((abbr (eq style 'age-abbreviated))
+-                                 (`(,cnt ,unit) (magit--age date abbr)))
+-                      (format (format (if abbr "%%2i%%-%ic" "%%2i %%-%is")
+-                                      (- width (if details (1+ details-width) 0)))
+-                              cnt unit)))
+-                  'face 'magit-log-date)))))))
++      (magit-log-format-author-margin author date))))
++
++(defun magit-log-format-author-margin (author date &optional previous-line)
++  (pcase-let ((`(,_ ,style ,width ,details ,details-width)
++               (or magit-buffer-margin
++                   (symbol-value option))))
++    (magit-make-margin-overlay
++     (concat (and details
++                  (concat (propertize (truncate-string-to-width
++                                       (or author "")
++                                       details-width
++                                       nil ?\s (make-string 1 magit-ellipsis))
++                                      'face 'magit-log-author)
++                          " "))
++             (propertize
++              (if (stringp style)
++                  (format-time-string
++                   style
++                   (seconds-to-time (string-to-number date)))
++                (pcase-let* ((abbr (eq style 'age-abbreviated))
++                             (`(,cnt ,unit) (magit--age date abbr)))
++                  (format (format (if abbr "%%2i%%-%ic" "%%2i %%-%is")
++                                  (- width (if details (1+ details-width) 0)))
++                          cnt unit)))
++              'face 'magit-log-date))
++     previous-line)))
+ 
+ (defun magit-log-format-shortstat-margin (rev)
+   (magit-make-margin-overlay
+-- 
+2.23.0
+