fix magit update

lisp/magit/magit-utils.el

@@ -1010,6 +1010,16 @@ one trailing newline is added."
                 (and (eq trim ?\n) "\n"))
       str)))
 
+(defun magit--version> (v1 v2)
+  "Return t if version V1 is higher (younger) than V2.
+This function should be named `version>' and be part of Emacs."
+  (version-list-< (version-to-list v2) (version-to-list v1)))
+
+(defun magit--version>= (v1 v2)
+  "Return t if version V1 is higher (younger) than or equal to V2.
+This function should be named `version>=' and be part of Emacs."
+  (version-list-<= (version-to-list v2) (version-to-list v1)))
+
 ;;; Kludges for Emacs Bugs
 
 (defun magit-file-accessible-directory-p (filename)
@@ -1019,7 +1029,7 @@ and https://github.com/magit/magit/issues/2295."
   (and (file-directory-p filename)
        (file-accessible-directory-p filename)))
 
-(when (version<= "25.1" emacs-version)
+(when (magit--version>= emacs-version "25.1")
   (with-eval-after-load 'vc-git
     (defun vc-git-conflicted-files (directory)
       "Return the list of files with conflicts in DIRECTORY."
@@ -1158,6 +1168,9 @@ or (last of all) the value of EXP."
 (advice-add 'Info-follow-nearest-node :around
             'Info-follow-nearest-node--magit-gitman)
 
+;; When making changes here, then also adjust the copy in docs/Makefile.
+;;;###autoload
+(advice-add 'org-man-export :around 'org-man-export--magit-gitman)
 ;;;###autoload
 (defun org-man-export--magit-gitman (fn link description format)
   (if (and (eq format 'texinfo)
@@ -1177,10 +1190,6 @@ the %s(1) manpage.
 ")
     (funcall fn link description format)))
 
-;;;###autoload
-(advice-add 'org-man-export :around
-            'org-man-export--magit-gitman)
-
 ;;; Kludges for Package Managers
 
 (defun magit--straight-chase-links (filename)
@@ -1198,6 +1207,32 @@ See <https://github.com/raxod502/straight.el/issues/520>."
         (setq filename target))))
   (file-chase-links filename))
 
+;;; Kludges for older Emacs versions
+
+(if (fboundp 'with-connection-local-variables)
+    (defalias 'magit--with-connection-local-variables
+      'with-connection-local-variables)
+  (defmacro magit--with-connection-local-variables (&rest body)
+    "Abridged `with-connection-local-variables' for pre Emacs 27 compatibility.
+Bind shell file name and switch for remote execution.
+`with-connection-local-variables' isn't available until Emacs 27.
+This kludge provides the minimal functionality required by
+Magit."
+    `(if (file-remote-p default-directory)
+         (pcase-let ((`(,shell-file-name ,shell-command-switch)
+                      (with-no-warnings ; about unknown tramp functions
+                        (require 'tramp)
+                        (let ((vec (tramp-dissect-file-name
+                                    default-directory)))
+                          (list (tramp-get-method-parameter
+                                 vec 'tramp-remote-shell)
+                                (mapconcat #'identity
+                                           (tramp-get-method-parameter
+                                            vec 'tramp-remote-shell-args)
+                                           " "))))))
+           ,@body)
+       ,@body)))
+
 ;;; Miscellaneous
 
 (defun magit-message (format-string &rest args)