[PATCH 2/4] gnus, notmuch: Share "attachment is patch?" logic

[Kyle Meyer <kyle@kyleam.com>]

This will gain another condition.  Avoid repeating it across two
spots.
---
 piem-gnus.el    | 4 ++--
 piem-notmuch.el | 4 ++--
 piem.el         | 5 +++++
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/piem-gnus.el b/piem-gnus.el
index 237eeb1..c1551ce 100644
--- a/piem-gnus.el
+++ b/piem-gnus.el
@@ -69,8 +69,8 @@ (defun piem-gnus-am-ready-mbox ()
              (delq nil
                    (mapcar (lambda (handle)
                              (and (listp handle)
-                                  (member (mm-handle-media-type handle)
-                                          '("text/x-diff" "text/x-patch"))
+                                  (piem-am-patch-attachment-p
+                                   (mm-handle-media-type handle))
                                   (with-temp-buffer
                                     (mm-display-inline handle)
                                     (buffer-substring-no-properties
diff --git a/piem-notmuch.el b/piem-notmuch.el
index cd3153a..ccfae75 100644
--- a/piem-notmuch.el
+++ b/piem-notmuch.el
@@ -91,8 +91,8 @@ (defun piem-notmuch-am-ready-mbox ()
          (let ((patches
                 (delq nil
                       (mapcar (lambda (part)
-                                (and (member (plist-get part :content-type)
-                                             '("text/x-diff" "text/x-patch"))
+                                (and (piem-am-patch-attachment-p
+                                      (plist-get part :content-type))
                                      (plist-get part :content)))
                               (plist-get body :content)))))
            (when patches
diff --git a/piem.el b/piem.el
index 784d0b3..9cc6a88 100644
--- a/piem.el
+++ b/piem.el
@@ -561,6 +561,11 @@ (defun piem-inject-thread-into-maildir (mid &optional message-only)
 \f
 ;;;; Patch handling
 
+(defun piem-am-patch-attachment-p (type)
+  "Return non-nil if an attachment should be treated as a patch.
+TYPE is a media type such as \"text/x-patch\"."
+  (member type '("text/x-diff" "text/x-patch")))
+
 (defun piem-extract-mbox-info (&optional buffer)
   "Collect information from message in BUFFER.
 If BUFFER is nil, the current buffer is used.  Any message after
-- 
2.29.2