[PATCH v2] Add ability to edit patches before applying them

[sourcehut@relevant-information.com]

From: Leo <sourcehut@relevant-information.com>

Sometimes it is necessary to edit patches before applying them.  These changes
allows you to do that by providing a new command `piem-edit` that
shows the buffer that is prepared by `piem-am-ready-mbox` to the user.
---
I wasn't sure if there were cases when `(kill-current-buffer)` could kill
the wrong buffer so I let-bound it to be safe.

I chose `generate-new-buffer` for the buffer name in
`piem-am-ready-mbox` because I thought sometimes the user could want to
open two edited patches side by side.  That is one of my annoyances with
mu4e anyways, not sure if it would actually be an issue in piem though.


 piem.el | 47 ++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 44 insertions(+), 3 deletions(-)

diff --git a/piem.el b/piem.el
index afe6b7a..eef0649 100644
--- a/piem.el
+++ b/piem.el
@@ -597,14 +597,18 @@ (defun piem--insert-message-id-header (mid)
             ;; blank line.  Assume we're in a header.
             (insert (format "Message-Id: <%s>\n" mid))))))))
 
-(defun piem-am-ready-mbox ()
+(defun piem-am-ready-mbox (&optional buffer-name)
   "Generate a buffer containing an am-ready mbox.
 The return value is (BUFFER . FORMAT), where FORMAT is either
 \"mbox\" or \"mboxrd\".  Callers are responsible for killing the
-buffer."
+buffer.
+
+By default the buffer name is hidden, but when BUFFER-NAME is
+non-nil, use that name instead."
   (when-let ((res (run-hook-with-args-until-success
                    'piem-am-ready-mbox-functions)))
-    (pcase-let ((buffer (generate-new-buffer " *piem am-ready mbox*"))
+    (pcase-let ((buffer (generate-new-buffer
+                         (or buffer-name " *piem am-ready mbox*")))
                 (`(,fn . ,format)
                  (if (member (cdr-safe res) '("mbox" "mboxrd"))
                      res
@@ -981,6 +985,43 @@ (defun piem-am (mbox &optional format info coderepo toggle-worktree)
         (magit-status-setup-buffer am-directory)
       (dired am-directory))))
 
+(defvar-local piem-edit-patch--coderepo nil)
+(defvar-local piem-edit-patch--format nil)
+
+(defun piem-edit ()
+  "Edit an am-ready mbox before feeding it to `git am'."
+  (interactive)
+  (pcase-let ((`(,mbox . ,format)
+               (or (piem-am-ready-mbox "*piem-edit-patch*")
+                   (user-error
+                    "Could not find am-ready mbox for current buffer")))
+              (coderepo (piem-inbox-coderepo)))
+    (pop-to-buffer mbox)
+    (piem-edit-patch-mode)
+    (setq piem-edit-patch--coderepo coderepo)
+    (setq piem-edit-patch--format format)))
+
+(defun piem-edit-patch-am ()
+  "Apply the patch that is currently edited."
+  (interactive)
+  (let ((buf (current-buffer)))
+    (piem-am  buf
+          "mbox"
+          (piem-extract-mbox-info (current-buffer))
+          piem-edit-patch--coderepo))
+  (kill-buffer buf))
+
+(defvar piem-edit-patch-mode-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map (kbd "C-c C-c") #'piem-edit-patch-am)
+    map)
+  "Keymap for editing patches with piem.")
+
+(define-derived-mode piem-edit-patch-mode text-mode "piem-edit-patch"
+  "Major mode for editing patches with piem."
+  :group 'piem
+  (buffer-enable-undo))
+
 \f
 ;;;; Dispatch
 

base-commit: e519aa44d148d5b8f22d7fe8844dc566046b04c2
-- 
2.34.1