format-patch: add --description-file option
This patch makes it possible to directly feed a branch description to derive the cover letter from. The use case is formatting dynamically created temporary commits which are not referenced anywhere. The most obvious alternative would be creating a temporary branch and setting a description on it, but that doesn't seem particularly elegant. Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Oswald Buddenhagen committed
Aug 21, 2023 at 19:07 UTC
67f4b36e339d91c06ff9cdc254864c830158e10f
3 files changed
+36
-3
Documentation/git-format-patch.txt
+4
@@ -215,6 +215,10 @@ is greater than 100 bytes, then the mode will be `message`, otherwise
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If `<mode>` is `none`, both the cover letter subject and body will be
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populated with placeholder text.
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+--description-file=<file>::
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+ Use the contents of <file> instead of the branch's description
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+ for generating the cover letter.
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+
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--subject-prefix=<subject prefix>::
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Instead of the standard '[PATCH]' prefix in the subject
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line, instead use '[<subject prefix>]'. This
builtin/log.c
+18
-3
@@ -1253,7 +1253,15 @@ static void show_diffstat(struct rev_info *rev,
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fprintf(rev->diffopt.file, "\n");
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}
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+static void read_desc_file(struct strbuf *buf, const char *desc_file)
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+{
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+ if (strbuf_read_file(buf, desc_file, 0) < 0)
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+ die_errno(_("unable to read branch description file '%s'"),
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+ desc_file);
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+}
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+
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static void prepare_cover_text(struct pretty_print_context *pp,
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+ const char *description_file,
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const char *branch_name,
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struct strbuf *sb,
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const char *encoding,
@@ -1267,7 +1275,9 @@ static void prepare_cover_text(struct pretty_print_context *pp,
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if (cover_from_description_mode == COVER_FROM_NONE)
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goto do_pp;
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- if (branch_name && *branch_name)
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+ if (description_file && *description_file)
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+ read_desc_file(&description_sb, description_file);
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+ else if (branch_name && *branch_name)
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read_branch_desc(&description_sb, branch_name);
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if (!description_sb.len)
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goto do_pp;
@@ -1313,6 +1323,7 @@ static void get_notes_args(struct strvec *arg, struct rev_info *rev)
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static void make_cover_letter(struct rev_info *rev, int use_separate_file,
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struct commit *origin,
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int nr, struct commit **list,
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+ const char *description_file,
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const char *branch_name,
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int quiet)
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{
@@ -1352,7 +1363,8 @@ static void make_cover_letter(struct rev_info *rev, int use_separate_file,
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pp.rev = rev;
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pp.print_email_subject = 1;
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pp_user_info(&pp, NULL, &sb, committer, encoding);
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- prepare_cover_text(&pp, branch_name, &sb, encoding, need_8bit_cte);
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+ prepare_cover_text(&pp, description_file, branch_name, &sb,
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+ encoding, need_8bit_cte);
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fprintf(rev->diffopt.file, "%s\n", sb.buf);
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strbuf_release(&sb);
@@ -1893,6 +1905,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
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int quiet = 0;
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const char *reroll_count = NULL;
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char *cover_from_description_arg = NULL;
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+ char *description_file = NULL;
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char *branch_name = NULL;
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char *base_commit = NULL;
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struct base_tree_info bases;
@@ -1936,6 +1949,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
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OPT_STRING(0, "cover-from-description", &cover_from_description_arg,
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N_("cover-from-description-mode"),
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N_("generate parts of a cover letter based on a branch's description")),
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+ OPT_FILENAME(0, "description-file", &description_file,
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+ N_("use branch description from file")),
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OPT_CALLBACK_F(0, "subject-prefix", &rev, N_("prefix"),
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N_("use [<prefix>] instead of [PATCH]"),
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PARSE_OPT_NONEG, subject_prefix_callback),
@@ -2321,7 +2336,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
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if (thread)
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gen_message_id(&rev, "cover");
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make_cover_letter(&rev, !!output_directory,
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- origin, nr, list, branch_name, quiet);
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+ origin, nr, list, description_file, branch_name, quiet);
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print_bases(&bases, rev.diffopt.file);
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print_signature(rev.diffopt.file);
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total++;
t/t4014-format-patch.sh
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@@ -1991,6 +1991,20 @@ test_expect_success 'cover letter using branch description (6)' '
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grep hello actual
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'
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+test_expect_success 'cover letter with --description-file' '
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+ test_when_finished "rm -f description.txt" &&
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+ cat >description.txt <<-\EOF &&
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+ subject from file
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+
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+ body from file
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+ EOF
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+ git checkout rebuild-1 &&
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+ git format-patch --stdout --cover-letter --cover-from-description auto \
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+ --description-file description.txt main >actual &&
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+ grep "^Subject: \[PATCH 0/2\] subject from file$" actual &&
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+ grep "^body from file$" actual
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+'
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+
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test_expect_success 'cover letter with nothing' '
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git format-patch --stdout --cover-letter >actual &&
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test_line_count = 0 actual