技巧分享
difftastic 是 Emacs 插件 deadgrep 作者写的一个根据语法进行结构性对比的命令行工具。
brew install difftastic
git config --global diff.external difft
然后我在 highlight-parentheses.el 作者的博客中学(抄)到了怎么在 magit 中使用 difftastic
https://tsdh.org/posts/2022-08-01-difftastic-diffing-with-magit.html
(require 'magit)
(defun my/magit--with-difftastic (buffer command)
"Run COMMAND with GIT_EXTERNAL_DIFF=difft then show result in BUFFER."
(let ((process-environment
(cons (concat "GIT_EXTERNAL_DIFF=difft --width="
(number-to-string (frame-width)))
process-environment)))
;; Clear the result buffer (we might regenerate a diff, e.g., for
;; the current changes in our working directory).
(with-current-buffer buffer
(setq buffer-read-only nil)
(erase-buffer))
;; Now spawn a process calling the git COMMAND.
(make-process
:name (buffer-name buffer)
:buffer buffer
:command command
;; Don't query for running processes when emacs is quit.
:noquery t
;; Show the result buffer once the process has finished.
:sentinel (lambda (proc event)
(when (eq (process-status proc) 'exit)
(with-current-buffer (process-buffer proc)
(goto-char (point-min))
(ansi-color-apply-on-region (point-min) (point-max))
(setq buffer-read-only t)
(view-mode)
(end-of-line)
;; difftastic diffs are usually 2-column side-by-side,
;; so ensure our window is wide enough.
(let ((width (current-column)))
(while (zerop (forward-line 1))
(end-of-line)
(setq width (max (current-column) width)))
;; Add column size of fringes
(setq width (+ width
(fringe-columns 'left)
(fringe-columns 'right)))
(goto-char (point-min))
(pop-to-buffer
(current-buffer)
`(;; If the buffer is that wide that splitting the frame in
;; two side-by-side windows would result in less than
;; 80 columns left, ensure it's shown at the bottom.
,(when (> 80 (- (frame-width) width))
#'display-buffer-at-bottom)
(window-width
. ,(min width (frame-width))))))))))))
(defun my/magit-show-with-difftastic (rev)
"Show the result of \"git show REV\" with GIT_EXTERNAL_DIFF=difft."
(interactive
(list (or
;; If REV is given, just use it.
(when (boundp 'rev) rev)
;; If not invoked with prefix arg, try to guess the REV from
;; point's position.
(and (not current-prefix-arg)
(or (magit-thing-at-point 'git-revision t)
(magit-branch-or-commit-at-point)))
;; Otherwise, query the user.
(magit-read-branch-or-commit "Revision"))))
(if (not rev)
(error "No revision specified")
(my/magit--with-difftastic
(get-buffer-create (concat "*git show difftastic " rev "*"))
(list "git" "--no-pager" "show" "--ext-diff" rev))))
(defun my/magit-diff-with-difftastic (arg)
"Show the result of \"git diff ARG\" with GIT_EXTERNAL_DIFF=difft."
(interactive
(list (or
;; If RANGE is given, just use it.
(when (boundp 'range) range)
;; If prefix arg is given, query the user.
(and current-prefix-arg
(magit-diff-read-range-or-commit "Range"))
;; Otherwise, auto-guess based on position of point, e.g., based on
;; if we are in the Staged or Unstaged section.
(pcase (magit-diff--dwim)
('unmerged (error "unmerged is not yet implemented"))
('unstaged nil)
('staged "--cached")
(`(stash . ,value) (error "stash is not yet implemented"))
(`(commit . ,value) (format "%s^..%s" value value))
((and range (pred stringp)) range)
(_ (magit-diff-read-range-or-commit "Range/Commit"))))))
(let ((name (concat "*git diff difftastic"
(if arg (concat " " arg) "")
"*")))
(my/magit--with-difftastic
(get-buffer-create name)
`("git" "--no-pager" "diff" "--ext-diff" ,@(when arg (list arg))))))
(transient-define-prefix my/magit-aux-commands ()
"My personal auxiliary magit commands."
["Auxiliary commands"
("d" "Difftastic Diff (dwim)" my/magit-diff-with-difftastic)
("s" "Difftastic Show" my/magit-show-with-difftastic)])
(transient-append-suffix 'magit-dispatch "!"
'("#" "My Magit Cmds" my/magit-aux-commands))
(define-key magit-status-mode-map (kbd "#") #'my/magit-aux-commands)
效果非常好
求助
只是有一个问题不太明白，如果我不写 (require 'magit) 运行会报错，但是写了又会让 magit 占用 Emacs 启动时间，有没有办法让这段代码在 magit 之后生效的方法啊？
试了下用 (with-eval-after-load 'magit )把上述代码包住，Emacs 启动时不报错了，但是还会在运行中报各种错误。
其实我只是个颜控，这几个工具的功能对我来说都是过剩的。
刚又触发了一下，不是报错，是 warning。