[PATCH 0/4] Update for Git's Message-Id to Message-ID switch

[PATCH 0/4] Update for Git's Message-Id to Message-ID switch

[Kyle Meyer]

git.git's ba4324c4e1 (e-mail workflow: Message-ID is spelled with ID
in both capital letters, 2023-04-03) has been merged to master.  With
that change, format-patch will insert a Message-ID header instead of
Message-Id.

This series prepares for those changes.  The only patch that
functionally matters is patch 2, which teaches piem-am-ready-mbox's
opt-in "insert message ID header" feature to look for either spelling
when checking whether it should _not_ insert a message ID because one
already exists.

  [1/4] piem-b4-am-from-mid: Tweak docstring for consistency
  [2/4] piem-am-ready-mbox: Adjust header regex for format-patch change
  [3/4] piem-am-ready-mbox: Change spelling of inserted message ID header
  [4/4] Switch remaining Message-Id headers to Message-ID

 piem-b4.el                |  2 +-
 piem.el                   | 13 ++++++++-----
 tests/piem-rmail-tests.el |  2 +-
 tests/piem-tests.el       | 22 ++++++++++++++++++++--
 4 files changed, 30 insertions(+), 9 deletions(-)


base-commit: d78900f06615e247cee5472beca4e7ae164fe77f
-- 
2.39.2

[PATCH 1/4] piem-b4-am-from-mid: Tweak docstring for consistency

[Kyle Meyer]

MID is used throughout the code base, and what it refers to is
probably clear enough without putting "Message-Id" in front of it.
(If it were to stay, it should probably be spelled "message ID").
---
 piem-b4.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/piem-b4.el b/piem-b4.el
index 8cbfc35a..cd19ebb3 100644
--- a/piem-b4.el
+++ b/piem-b4.el
@@ -131,7 +131,7 @@ (defun piem-b4-am-ready-from-mid (mid &optional args)
 (defun piem-b4-am-from-mid (mid &optional args toggle-worktree)
   "Get the thread for MID, extract an am-ready mbox, and apply it.
 
-Try to generate a thread for the Message-Id MID with
+Try to generate a thread for MID with
 `piem-mid-to-thread-functions'.  If that fails, try to download
 the thread from an inbox URL associated with the current buffer,
 provided that the current buffer's message ID matches MID.  And
-- 
2.39.2

[PATCH 2/4] piem-am-ready-mbox: Adjust header regex for format-patch change

[Kyle Meyer]

As of git.git's ba4324c4e1 (e-mail workflow: Message-ID is spelled
with ID in both capital letters, 2023-04-03), git-format-patch inserts
a Message-ID header instead of Message-Id.  Teach
piem--insert-message-id-header to look for either variants when it
checks for an existing header.

Another option would be to ignore the header case entirely.  However,
piem--insert-message-id-header is intended to work only for
format-patch output, so stick with the stricter header matching.
---
 piem.el             |  5 ++++-
 tests/piem-tests.el | 18 ++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/piem.el b/piem.el
index 63c358a2..9dc7f3e3 100644
--- a/piem.el
+++ b/piem.el
@@ -601,8 +601,11 @@ (defun piem--insert-message-id-header (mid)
                             (rx line-start (zero-or-one space) line-end))))
             (cond
              ((looking-at-p
+               ;; git-format-patch switched to "Message-ID" spelling
+               ;; in v2.41.
                (rx line-start
-                   "Message-Id: <" (one-or-more not-newline) ">"
+                   "Message-" (or "Id" "ID")
+                   ": <" (one-or-more not-newline) ">"
                    line-end))
               (throw 'has-message-id nil))
              ((looking-at-p
diff --git a/tests/piem-tests.el b/tests/piem-tests.el
index 79d8591e..6f39a53e 100644
--- a/tests/piem-tests.el
+++ b/tests/piem-tests.el
@@ -179,6 +179,24 @@ (ert-deftest piem--insert-message-id-header ()
   (should-not
    (with-temp-buffer
      (piem--insert-message-id-header "msg@id")))
+  (should-not
+   (string-match-p
+    "Message-Id: <msg@id>"
+    (with-temp-buffer
+      (insert "\
+From 0d732713af1f3fb48b37430e2cd0a3033cea14f3 Mon Sep 17 00:00:00 2001
+From: Foo Bar <f@example.com>
+Message-ID: <existing@id>
+Date: Fri, 22 Jan 2021 22:35:58 -0500
+Subject: [PATCH] a
+
+---
+ a | 1 +
+ 1 file changed, 1 insertion(+)
+ create mode 100644 a")
+      (goto-char (point-min))
+      (piem--insert-message-id-header "msg@id")
+      (buffer-string))))
   (should
    (string-match-p
     (concat
-- 
2.39.2

[PATCH 3/4] piem-am-ready-mbox: Change spelling of inserted message ID header

[Kyle Meyer]

format-patch changed from Message-Id to Message-ID in git.git's
ba4324c4e1 (e-mail workflow: Message-ID is spelled with ID in both
capital letters, 2023-04-03).  Update piem--insert-message-id-header
to follow Git's change.
---
 piem.el             | 6 +++---
 tests/piem-tests.el | 6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/piem.el b/piem.el
index 9dc7f3e3..01985f0e 100644
--- a/piem.el
+++ b/piem.el
@@ -156,10 +156,10 @@ (defcustom piem-am-ready-mbox-functions nil
   :type 'hook)
 
 (defcustom piem-add-message-id-header nil
-  "Whether to add Message-Id header to non-mail patches.
+  "Whether to add Message-ID header to non-mail patches.
 If this value is non-nil and a patch returned by a function in
 `piem-am-ready-mbox-functions' looks like a patch that was
-attached rather than sent inline, add a Message-Id header with
+attached rather than sent inline, add a Message-ID header with
 the return value of `piem-mid'."
   :type 'boolean)
 
@@ -615,7 +615,7 @@ (defun piem--insert-message-id-header (mid)
           (when (= header-count 3)
             ;; Found all the expected headers before hitting a
             ;; blank line.  Assume we're in a header.
-            (insert (format "Message-Id: <%s>\n" mid))))))))
+            (insert (format "Message-ID: <%s>\n" mid))))))))
 
 (defun piem-am-ready-mbox (&optional buffer-name)
   "Generate a buffer containing an am-ready mbox.
diff --git a/tests/piem-tests.el b/tests/piem-tests.el
index 6f39a53e..7f9f30f3 100644
--- a/tests/piem-tests.el
+++ b/tests/piem-tests.el
@@ -181,7 +181,7 @@ (ert-deftest piem--insert-message-id-header ()
      (piem--insert-message-id-header "msg@id")))
   (should-not
    (string-match-p
-    "Message-Id: <msg@id>"
+    "Message-ID: <msg@id>"
     (with-temp-buffer
       (insert "\
 From 0d732713af1f3fb48b37430e2cd0a3033cea14f3 Mon Sep 17 00:00:00 2001
@@ -200,9 +200,9 @@ (ert-deftest piem--insert-message-id-header ()
   (should
    (string-match-p
     (concat
-     (rx "Subject: [PATCH 1/2] a\nMessage-Id: <msg@id>\n"
+     (rx "Subject: [PATCH 1/2] a\nMessage-ID: <msg@id>\n"
          (one-or-more anychar)
-         "Subject: [PATCH 2/2] b\nMessage-Id: <msg@id>\n"))
+         "Subject: [PATCH 2/2] b\nMessage-ID: <msg@id>\n"))
     (with-temp-buffer
       (insert "\
 From 0d732713af1f3fb48b37430e2cd0a3033cea14f3 Mon Sep 17 00:00:00 2001
-- 
2.39.2

[PATCH 4/4] Switch remaining Message-Id headers to Message-ID

[Kyle Meyer]

The two previous commits updated the piem-add-message-id-header
functionality for git.git's change from Message-Id to Message-ID.
Updates a couple of remaining spots to use Message-ID for consistency.
---
 piem.el                   | 2 +-
 tests/piem-rmail-tests.el | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/piem.el b/piem.el
index 01985f0e..abc87b10 100644
--- a/piem.el
+++ b/piem.el
@@ -759,7 +759,7 @@ (defun piem--write-mbox-to-maildir (maildir-directory)
                                      (save-excursion
                                        (message-narrow-to-head-1)
                                        (message-fetch-field "message-id" t)))
-                                   (error "Message lacks Message-Id header")))))))
+                                   (error "Message lacks Message-ID header")))))))
             (cl-incf n-skipped)
           (let ((case-fold-search nil))
             (while (re-search-forward
diff --git a/tests/piem-rmail-tests.el b/tests/piem-rmail-tests.el
index f56e2f26..7ee0a553 100644
--- a/tests/piem-rmail-tests.el
+++ b/tests/piem-rmail-tests.el
@@ -38,7 +38,7 @@ (defvar piem-rmail-tests-mbox-text "\
 Cc: i@inbox.example.com
 Subject: Re: test
 Date: Sun, 23 May 2021 02:26:51 -0400
-Message-Id: <456@example.com>
+Message-ID: <456@example.com>
 In-Reply-To: <123@example.com>
 References: <123@example.com>
 
-- 
2.39.2

Re: [PATCH 2/4] piem-am-ready-mbox: Adjust header regex for format-patch change

[Kyle Meyer]

Kyle Meyer writes:

> a Message-ID header instead of Message-Id.  Teach
> piem--insert-message-id-header to look for either variants when it

s/variants/variant/

Re: [PATCH 3/4] piem-am-ready-mbox: Change spelling of inserted message ID header

[Kyle Meyer]

Kyle Meyer writes:

> format-patch changed from Message-Id to Message-ID in git.git's
> ba4324c4e1 [...]

When applying, I'll rephrase this a bit for clarity.