teach format-patch to place other authors into in-body "From"
authorJeff King <peff@peff.net>
Wed, 3 Jul 2013 07:08:22 +0000 (03:08 -0400)
committerJunio C Hamano <gitster@pobox.com>
Wed, 3 Jul 2013 19:11:04 +0000 (12:11 -0700)
Format-patch generates emails with the "From" address set to the
author of each patch. If you are going to send the emails, however,
you would want to replace the author identity with yours (if they
are not the same), and bump the author identity to an in-body
header.

Normally this is handled by git-send-email, which does the
transformation before sending out the emails. However, some
workflows may not use send-email (e.g., imap-send, or a custom
script which feeds the mbox to a non-git MUA). They could each
implement this feature themselves, but getting it right is
non-trivial (one must canonicalize the identities by reversing any
RFC2047 encoding or RFC822 quoting of the headers, which has caused
many bugs in send-email over the years).

This patch takes a different approach: it teaches format-patch a
"--from" option which handles the ident check and in-body header
while it is writing out the email. It's much simpler to do at this
level (because we haven't done any quoting yet), and any workflow
based on format-patch can easily turn it on.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Documentation/git-format-patch.txt
builtin/log.c
commit.h
log-tree.c
pretty.c
revision.h
t/t4014-format-patch.sh
index 39118774afbbd730e4464f44e24a05af91432c30..e394276b1a2e2edfbbf8ab1dea9fcd30ca66e61f 100644 (file)
@@ -187,6 +187,21 @@ will want to ensure that threading is disabled for `git send-email`.
        The negated form `--no-cc` discards all `Cc:` headers added so
        far (from config or command line).
 
+--from::
+--from=<ident>::
+       Use `ident` in the `From:` header of each commit email. If the
+       author ident of the commit is not textually identical to the
+       provided `ident`, place a `From:` header in the body of the
+       message with the original author. If no `ident` is given, use
+       the committer ident.
++
+Note that this option is only useful if you are actually sending the
+emails and want to identify yourself as the sender, but retain the
+original author (and `git am` will correctly pick up the in-body
+header). Note also that `git send-email` already handles this
+transformation for you, and this option should not be used if you are
+feeding the result to `git send-email`.
+
 --add-header=<header>::
        Add an arbitrary header to the email headers.  This is in addition
        to any configured headers, and may be used multiple times.
index e3222ed9f979e3140cbfc88ad2839c573c89bf06..2625f9881ad836d1a3e303f4c159d6b76a3ae04f 100644 (file)
@@ -1112,6 +1112,21 @@ static int cc_callback(const struct option *opt, const char *arg, int unset)
        return 0;
 }
 
+static int from_callback(const struct option *opt, const char *arg, int unset)
+{
+       char **from = opt->value;
+
+       free(*from);
+
+       if (unset)
+               *from = NULL;
+       else if (arg)
+               *from = xstrdup(arg);
+       else
+               *from = xstrdup(git_committer_info(IDENT_NO_DATE));
+       return 0;
+}
+
 int cmd_format_patch(int argc, const char **argv, const char *prefix)
 {
        struct commit *commit;
@@ -1134,6 +1149,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
        int quiet = 0;
        int reroll_count = -1;
        char *branch_name = NULL;
+       char *from = NULL;
        const struct option builtin_format_patch_options[] = {
                { OPTION_CALLBACK, 'n', "numbered", &numbered, NULL,
                            N_("use [PATCH n/m] even with a single patch"),
@@ -1177,6 +1193,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                            0, to_callback },
                { OPTION_CALLBACK, 0, "cc", NULL, N_("email"), N_("add Cc: header"),
                            0, cc_callback },
+               { OPTION_CALLBACK, 0, "from", &from, N_("ident"),
+                           N_("set From address to <ident> (or committer ident if absent)"),
+                           PARSE_OPT_OPTARG, from_callback },
                OPT_STRING(0, "in-reply-to", &in_reply_to, N_("message-id"),
                            N_("make first mail a reply to <message-id>")),
                { OPTION_CALLBACK, 0, "attach", &rev, N_("boundary"),
@@ -1264,6 +1283,11 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 
        rev.extra_headers = strbuf_detach(&buf, NULL);
 
+       if (from) {
+               if (split_ident_line(&rev.from_ident, from, strlen(from)))
+                       die(_("invalid ident line: %s"), from);
+       }
+
        if (start_number < 0)
                start_number = 1;
 
index 011ddb146f4699a7333f4db3689f4eaac997bb10..c56bc3a0914f9fce3e8b5d0a25d291077429fe03 100644 (file)
--- a/commit.h
+++ b/commit.h
@@ -6,6 +6,7 @@
 #include "strbuf.h"
 #include "decorate.h"
 #include "gpg-interface.h"
+#include "string-list.h"
 
 struct commit_list {
        struct commit *item;
@@ -95,11 +96,15 @@ struct pretty_print_context {
        const char *output_encoding;
        struct string_list *mailmap;
        int color;
+       struct ident_split *from_ident;
 
        /*
         * Fields below here are manipulated internally by pp_* functions and
         * should not be counted on by callers.
         */
+
+       /* Manipulated by the pp_* functions internally. */
+       struct string_list in_body_headers;
 };
 
 struct userformat_want {
index 2eb69bcfed096d28bff736deca715458605d902a..67da27f909067132c79fdc028679895e280b7ab1 100644 (file)
@@ -617,6 +617,8 @@ void show_log(struct rev_info *opt)
        ctx.fmt = opt->commit_format;
        ctx.mailmap = opt->mailmap;
        ctx.color = opt->diffopt.use_color;
+       if (opt->from_ident.mail_begin && opt->from_ident.name_begin)
+               ctx.from_ident = &opt->from_ident;
        pretty_print_commit(&ctx, commit, &msgbuf);
 
        if (opt->add_signoff)
index 68cd7a035b4c3fe4cea00c903bc5113d583aa08d..74563c92b4cdce8e947a2816a8b56355b11439e6 100644 (file)
--- a/pretty.c
+++ b/pretty.c
@@ -432,6 +432,23 @@ void pp_user_info(struct pretty_print_context *pp,
                map_user(pp->mailmap, &mailbuf, &maillen, &namebuf, &namelen);
 
        if (pp->fmt == CMIT_FMT_EMAIL) {
+               if (pp->from_ident) {
+                       struct strbuf buf = STRBUF_INIT;
+
+                       strbuf_addstr(&buf, "From: ");
+                       strbuf_add(&buf, namebuf, namelen);
+                       strbuf_addstr(&buf, " <");
+                       strbuf_add(&buf, mailbuf, maillen);
+                       strbuf_addstr(&buf, ">\n");
+                       string_list_append(&pp->in_body_headers,
+                                          strbuf_detach(&buf, NULL));
+
+                       mailbuf = pp->from_ident->mail_begin;
+                       maillen = pp->from_ident->mail_end - mailbuf;
+                       namebuf = pp->from_ident->name_begin;
+                       namelen = pp->from_ident->name_end - namebuf;
+               }
+
                strbuf_addstr(sb, "From: ");
                if (needs_rfc2047_encoding(namebuf, namelen, RFC2047_ADDRESS)) {
                        add_rfc2047(sb, namebuf, namelen,
@@ -1602,6 +1619,16 @@ void pp_title_line(struct pretty_print_context *pp,
        }
        strbuf_addch(sb, '\n');
 
+       if (need_8bit_cte == 0) {
+               int i;
+               for (i = 0; i < pp->in_body_headers.nr; i++) {
+                       if (has_non_ascii(pp->in_body_headers.items[i].string)) {
+                               need_8bit_cte = 1;
+                               break;
+                       }
+               }
+       }
+
        if (need_8bit_cte > 0) {
                const char *header_fmt =
                        "MIME-Version: 1.0\n"
@@ -1615,6 +1642,17 @@ void pp_title_line(struct pretty_print_context *pp,
        if (pp->fmt == CMIT_FMT_EMAIL) {
                strbuf_addch(sb, '\n');
        }
+
+       if (pp->in_body_headers.nr) {
+               int i;
+               for (i = 0; i < pp->in_body_headers.nr; i++) {
+                       strbuf_addstr(sb, pp->in_body_headers.items[i].string);
+                       free(pp->in_body_headers.items[i].string);
+               }
+               string_list_clear(&pp->in_body_headers, 0);
+               strbuf_addch(sb, '\n');
+       }
+
        strbuf_release(&title);
 }
 
index 92d6614af6da62160219b0df40d0caf56335ffce..95859ba119033ba17346c701493df1474eec5df2 100644 (file)
@@ -144,6 +144,7 @@ struct rev_info {
        int             numbered_files;
        int             reroll_count;
        char            *message_id;
+       struct ident_split from_ident;
        struct string_list *ref_message_ids;
        int             add_signoff;
        const char      *extra_headers;
index 58d418098d793b284bb4a7222cf9709c45b26c90..668933bfb2c906ce9f8c74ab498f1986b56aced0 100755 (executable)
@@ -972,6 +972,49 @@ test_expect_success 'empty subject prefix does not have extra space' '
        test_cmp expect actual
 '
 
+test_expect_success '--from=ident notices bogus ident' '
+       test_must_fail git format-patch -1 --stdout --from=foo >patch
+'
+
+test_expect_success '--from=ident replaces author' '
+       git format-patch -1 --stdout --from="Me <me@example.com>" >patch &&
+       cat >expect <<-\EOF &&
+       From: Me <me@example.com>
+
+       From: A U Thor <author@example.com>
+
+       EOF
+       sed -ne "/^From:/p; /^$/p; /^---$/q" <patch >patch.head &&
+       test_cmp expect patch.head
+'
+
+test_expect_success '--from uses committer ident' '
+       git format-patch -1 --stdout --from >patch &&
+       cat >expect <<-\EOF &&
+       From: C O Mitter <committer@example.com>
+
+       From: A U Thor <author@example.com>
+
+       EOF
+       sed -ne "/^From:/p; /^$/p; /^---$/q" <patch >patch.head &&
+       test_cmp expect patch.head
+'
+
+test_expect_success 'in-body headers trigger content encoding' '
+       GIT_AUTHOR_NAME="éxötìc" test_commit exotic &&
+       test_when_finished "git reset --hard HEAD^" &&
+       git format-patch -1 --stdout --from >patch &&
+       cat >expect <<-\EOF &&
+       From: C O Mitter <committer@example.com>
+       Content-Type: text/plain; charset=UTF-8
+
+       From: éxötìc <author@example.com>
+
+       EOF
+       sed -ne "/^From:/p; /^$/p; /^Content-Type/p; /^---$/q" <patch >patch.head &&
+       test_cmp expect patch.head
+'
+
 append_signoff()
 {
        C=$(git commit-tree HEAD^^{tree} -p HEAD) &&