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[PATCH v3 13/13] format-patch: learn --infer-cover-subject option

From
Denton Liu <liu.denton@gmail.com>
Date
Aug 20, 2019, 07:19 UTC
Message-ID
<de599f7ca9b5fe7e298bba0bb8c5d05f2f5cf34f.1566285151.git.liu.denton@gmail.com>
In-Reply-To
<cover.1566285151.git.liu.denton@gmail.com>

Teach format-patch to use the first line of the branch description as the Subject: of the generated cover letter, rather than "*** SUBJECT HERE ***" if `--infer-cover-subject` is specified or the corresponding `format.inferCoverSubject` option is enabled. This complements the existing inclusion of the branch description in the cover letter body.

The reason why this behaviour is not made default is because this change is not backwards compatible and may break existing tooling that may rely on the default template subject.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
---
 Documentation/config/format.txt    |  6 ++++
 Documentation/git-format-patch.txt |  7 ++++
 builtin/log.c                      | 56 +++++++++++++++++++-----------
 t/t4014-format-patch.sh            | 35 ++++++++++++++++++-
 4 files changed, 82 insertions(+), 22 deletions(-)
diff --git a/Documentation/config/format.txt b/Documentation/config/format.txt
index cb629fa769..2723566289 100644
--- a/Documentation/config/format.txt
+++ b/Documentation/config/format.txt
@@ -36,6 +36,12 @@ format.subjectPrefix::
 	The default for format-patch is to output files with the '[PATCH]'
 	subject prefix. Use this variable to change that prefix.
 
+format.inferCoverSubject::
+	A boolean that controls whether or not to take the first line of
+	the branch description as the subject for the cover letter. See the
+	`--infer-cover-subject` option in linkgit:git-format-patch[1].
+	Default is false.
+
 format.signature::
 	The default for format-patch is to output a signature containing
 	the Git version number. Use this variable to change that default.
diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
index 95bc4d53ca..c5bc0bf5c6 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt
@@ -19,6 +19,7 @@ SYNOPSIS
 		   [--start-number <n>] [--numbered-files]
 		   [--in-reply-to=<Message-Id>] [--suffix=.<sfx>]
 		   [--ignore-if-in-upstream]
+		   [--[no-]infer-cover-subject]
 		   [--rfc] [--subject-prefix=<Subject-Prefix>]
 		   [(--reroll-count|-v) <n>]
 		   [--to=<email>] [--cc=<email>]
@@ -171,6 +172,11 @@ will want to ensure that threading is disabled for `git send-email`.
 	patches being generated, and any patch that matches is
 	ignored.
 
+--[no-]infer-cover-subject::
+	Use the beginning of the branch description (up to the first
+	blank line) as the cover letter subject instead of the default
+	"*** SUBJECT HERE ***".
+
 --subject-prefix=<Subject-Prefix>::
 	Instead of the standard '[PATCH]' prefix in the subject
 	line, instead use '[<Subject-Prefix>]'. This
@@ -347,6 +353,7 @@ with configuration variables.
 	signOff = true
 	outputDirectory = <directory>
 	coverLetter = auto
+	inferCoverSubject = true
 ------------
 
 
diff --git a/builtin/log.c b/builtin/log.c
index 44b10b3415..a19b746495 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -774,6 +774,7 @@ static const char *signature = git_version_string;
 static const char *signature_file;
 static int config_cover_letter;
 static const char *config_output_directory;
+static int infer_cover_subject;
 
 enum {
 	COVER_UNSET,
@@ -887,6 +888,10 @@ static int git_format_config(const char *var, const char *value, void *cb)
 		}
 		return 0;
 	}
+	if (!strcmp(var, "format.infercoversubject")) {
+		infer_cover_subject = git_config_bool(var, value);
+		return 0;
+	}
 
 	return git_log_config(var, value, cb);
 }
@@ -993,20 +998,6 @@ static void print_signature(FILE *file)
 	putc('\n', file);
 }
 
-static void add_branch_description(struct strbuf *buf, const char *branch_name)
-{
-	struct strbuf desc = STRBUF_INIT;
-	if (!branch_name || !*branch_name)
-		return;
-	read_branch_desc(&desc, branch_name);
-	if (desc.len) {
-		strbuf_addch(buf, '\n');
-		strbuf_addbuf(buf, &desc);
-		strbuf_addch(buf, '\n');
-	}
-	strbuf_release(&desc);
-}
-
 static char *find_branch_name(struct rev_info *rev)
 {
 	int i, positive = -1;
@@ -1057,13 +1048,17 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
 			      struct commit *origin,
 			      int nr, struct commit **list,
 			      const char *branch_name,
+			      int infer_subject,
 			      int quiet)
 {
 	const char *committer;
-	const char *body = "*** SUBJECT HERE ***\n\n*** BLURB HERE ***\n";
-	const char *msg;
+	const char *subject = "*** SUBJECT HERE ***";
+	const char *body = "*** BLURB HERE ***";
+	const char *description = NULL;
 	struct shortlog log;
 	struct strbuf sb = STRBUF_INIT;
+	struct strbuf description_sb = STRBUF_INIT;
+	struct strbuf subject_sb = STRBUF_INIT;
 	int i;
 	const char *encoding = "UTF-8";
 	int need_8bit_cte = 0;
@@ -1091,17 +1086,34 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
 	if (!branch_name)
 		branch_name = find_branch_name(rev);
 
-	msg = body;
+	if (branch_name && *branch_name)
+		read_branch_desc(&description_sb, branch_name);
+
+	if (description_sb.len) {
+		if (infer_subject) {
+			description = format_subject(&subject_sb, description_sb.buf, " ");
+			subject = subject_sb.buf;
+		} else {
+			description = description_sb.buf;
+		}
+	}
+
 	pp.fmt = CMIT_FMT_EMAIL;
 	pp.date_mode.type = DATE_RFC2822;
 	pp.rev = rev;
 	pp.print_email_subject = 1;
 	pp_user_info(&pp, NULL, &sb, committer, encoding);
-	pp_title_line(&pp, &msg, &sb, encoding, need_8bit_cte);
-	pp_remainder(&pp, &msg, &sb, 0);
-	add_branch_description(&sb, branch_name);
+	pp_title_line(&pp, &subject, &sb, encoding, need_8bit_cte);
+	pp_remainder(&pp, &body, &sb, 0);
+	if (description) {
+		strbuf_addch(&sb, '\n');
+		strbuf_addstr(&sb, description);
+		strbuf_addch(&sb, '\n');
+	}
 	fprintf(rev->diffopt.file, "%s\n", sb.buf);
 
+	strbuf_release(&description_sb);
+	strbuf_release(&subject_sb);
 	strbuf_release(&sb);
 
 	shortlog_init(&log);
@@ -1577,6 +1589,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		{ OPTION_CALLBACK, 0, "rfc", &rev, NULL,
 			    N_("Use [RFC PATCH] instead of [PATCH]"),
 			    PARSE_OPT_NOARG | PARSE_OPT_NONEG, rfc_callback },
+		OPT_BOOL(0, "infer-cover-subject", &infer_cover_subject,
+			    N_("infer a cover letter subject from branch description")),
 		{ OPTION_CALLBACK, 0, "subject-prefix", &rev, N_("prefix"),
 			    N_("Use [<prefix>] instead of [PATCH]"),
 			    PARSE_OPT_NONEG, subject_prefix_callback },
@@ -1916,7 +1930,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		if (thread)
 			gen_message_id(&rev, "cover");
 		make_cover_letter(&rev, use_stdout,
-				  origin, nr, list, branch_name, quiet);
+				  origin, nr, list, branch_name, infer_cover_subject, quiet);
 		print_bases(&bases, rev.diffopt.file);
 		print_signature(rev.diffopt.file);
 		total++;
diff --git a/t/t4014-format-patch.sh b/t/t4014-format-patch.sh
index 7b8c8fe136..94a3191aca 100755
--- a/t/t4014-format-patch.sh
+++ b/t/t4014-format-patch.sh
@@ -822,7 +822,7 @@ test_expect_success 'format-patch --ignore-if-in-upstream HEAD' '
 '
 
 test_expect_success 'get git version' '
-	git_version="$(git --version | sed "s/.* //")"
+	git_version="$(git --version >version && sed "s/.* //" <version)"
 '
 
 signature() {
@@ -1516,6 +1516,39 @@ test_expect_success 'format patch ignores color.ui' '
 	test_cmp expect actual
 '
 
+test_expect_success 'cover letter with config subject' '
+	test_config branch.rebuild-1.description "config subject
+
+body" &&
+	test_config format.inferCoverSubject true &&
+	git checkout rebuild-1 &&
+	git format-patch --stdout --cover-letter master >actual &&
+	grep "^Subject: \[PATCH 0/2\] config subject$" actual &&
+	grep "^body" actual
+'
+
+test_expect_success 'cover letter with command-line subject' '
+	test_config branch.rebuild-1.description "command-line subject
+
+body" &&
+	git checkout rebuild-1 &&
+	git format-patch --stdout --cover-letter --infer-cover-subject master >actual &&
+	grep "^Subject: \[PATCH 0/2\] command-line subject$" actual &&
+	grep "^body" actual
+'
+
+test_expect_success 'cover letter with command-line --no-infer-cover-subject overrides config' '
+	test_config branch.rebuild-1.description "config subject
+
+body" &&
+	test_config format.inferCoverSubject true &&
+	git checkout rebuild-1 &&
+	git format-patch --stdout --cover-letter --no-infer-cover-subject master >actual &&
+	grep "^Subject: \[PATCH 0/2\] \*\*\* SUBJECT HERE \*\*\*$" actual &&
+	grep "^config subject" actual &&
+	grep "^body" actual
+'
+
 test_expect_success 'cover letter using branch description (1)' '
 	git checkout rebuild-1 &&
 	test_config branch.rebuild-1.description hello &&

-- 
2.23.0.248.g3a9dd8fb08
Previous: Denton LiuNext: Junio C Hamano
Message 28 of 91 in “format-patch: learn --infer-cover-subject option”
  1. 0/4 format-patch: learn --infer-cover-subject optionDenton Liu, Aug 19, 2019
  2. 1/4 t4014: clean up styleDenton Liu, Aug 19, 2019
  3. Eric SunshineAug 20, 2019
  4. 2/4 Doc: add more detail for git-format-patchDenton Liu, Aug 19, 2019
  5. Eric SunshineAug 20, 2019
  6. Denton LiuAug 20, 2019
  7. 3/4 config/format.txt: make clear the default value of format.coverLetterDenton Liu, Aug 19, 2019
  8. Eric SunshineAug 20, 2019
  9. 4/4 format-patch: learn --infer-cover-letter optionDenton Liu, Aug 19, 2019
  10. Eric SunshineAug 20, 2019
  11. 00/13 format-patch: learn --infer-cover-subject option (also t4014 cleanup)Denton Liu, Aug 20, 2019
  12. 01/13 t4014: drop unnecessary blank lines from test casesDenton Liu, Aug 20, 2019
  13. 02/13 t4014: s/expected/expect/Denton Liu, Aug 20, 2019
  14. Eric SunshineAug 20, 2019
  15. 03/13 t4014: move closing sq onto its own lineDenton Liu, Aug 20, 2019
  16. 04/13 t4014: use sq for test case namesDenton Liu, Aug 20, 2019
  17. 05/13 t4014: remove spaces after redirect operatorsDenton Liu, Aug 20, 2019
  18. 06/13 t4014: use indentable here-docsDenton Liu, Aug 20, 2019
  19. 07/13 t4014: drop redirections to /dev/nullDenton Liu, Aug 20, 2019
  20. 08/13 t4014: use test_line_count() where possibleDenton Liu, Aug 20, 2019
  21. 09/13 t4014: remove confusing pipe in check_threading()Denton Liu, Aug 20, 2019
  22. 10/13 t4014: stop losing return codes of git commandsDenton Liu, Aug 20, 2019
  23. Denton LiuAug 20, 2019
  24. Johannes SixtAug 20, 2019
  25. 11/13 Doc: add more detail for git-format-patchDenton Liu, Aug 20, 2019
  26. Junio C HamanoAug 21, 2019
  27. 12/13 config/format.txt: specify default value of format.coverLetterDenton Liu, Aug 20, 2019
  28. 13/13 format-patch: learn --infer-cover-subject optionDenton Liu, Aug 20, 2019
  29. Junio C HamanoAug 21, 2019
  30. Denton LiuAug 23, 2019
  31. Philip OakleyAug 23, 2019
  32. Junio C HamanoAug 23, 2019
  33. Denton LiuAug 24, 2019
  34. Philip OakleyAug 24, 2019
  35. Junio C HamanoAug 26, 2019
  36. Junio C HamanoAug 26, 2019
  37. Junio C HamanoAug 26, 2019
  38. Junio C HamanoAug 22, 2019
  39. Denton LiuAug 23, 2019
  40. Junio C HamanoAug 23, 2019
  41. 00/13 format-patch: clean up tests and documentationDenton Liu, Aug 24, 2019
  42. 01/13 t4014: drop unnecessary blank lines from test casesDenton Liu, Aug 24, 2019
  43. 02/13 t4014: s/expected/expect/Denton Liu, Aug 24, 2019
  44. 03/13 t4014: move closing sq onto its own lineDenton Liu, Aug 24, 2019
  45. 04/13 t4014: use sq for test case namesDenton Liu, Aug 24, 2019
  46. 05/13 t4014: remove spaces after redirect operatorsDenton Liu, Aug 24, 2019
  47. 06/13 t4014: use indentable here-docsDenton Liu, Aug 24, 2019
  48. 07/13 t4014: drop redirections to /dev/nullDenton Liu, Aug 24, 2019
  49. 08/13 t4014: let sed open its own filesDenton Liu, Aug 24, 2019
  50. Eric SunshineAug 26, 2019
  51. 09/13 t4014: use test_line_count() where possibleDenton Liu, Aug 24, 2019
  52. 10/13 t4014: remove confusing pipe in check_threading()Denton Liu, Aug 24, 2019
  53. 11/13 t4014: stop losing return codes of git commandsDenton Liu, Aug 24, 2019
  54. 12/13 Doc: add more detail for git-format-patchDenton Liu, Aug 24, 2019
  55. Junio C HamanoAug 26, 2019
  56. Junio C HamanoAug 26, 2019
  57. 13/13 config/format.txt: specify default value of format.coverLetterDenton Liu, Aug 24, 2019
  58. Denton LiuAug 24, 2019
  59. Junio C HamanoAug 26, 2019
  60. 00/13 format-patch: clean up tests and documentationDenton Liu, Aug 27, 2019
  61. 01/13 t4014: drop unnecessary blank lines from test casesDenton Liu, Aug 27, 2019
  62. 02/13 t4014: s/expected/expect/Denton Liu, Aug 27, 2019
  63. 03/13 t4014: move closing sq onto its own lineDenton Liu, Aug 27, 2019
  64. 04/13 t4014: use sq for test case namesDenton Liu, Aug 27, 2019
  65. 05/13 t4014: remove spaces after redirect operatorsDenton Liu, Aug 27, 2019
  66. 06/13 t4014: use indentable here-docsDenton Liu, Aug 27, 2019
  67. 07/13 t4014: drop redirections to /dev/nullDenton Liu, Aug 27, 2019
  68. 08/13 t4014: let sed open its own filesDenton Liu, Aug 27, 2019
  69. 09/13 t4014: use test_line_count() where possibleDenton Liu, Aug 27, 2019
  70. 10/13 t4014: remove confusing pipe in check_threading()Denton Liu, Aug 27, 2019
  71. 11/13 t4014: stop losing return codes of git commandsDenton Liu, Aug 27, 2019
  72. 12/13 Doc: add more detail for git-format-patchDenton Liu, Aug 27, 2019
  73. 13/13 config/format.txt: specify default value of format.coverLetterDenton Liu, Aug 27, 2019
  74. Denton LiuSep 4, 2019
  75. Junio C HamanoSep 5, 2019
  76. Denton LiuSep 5, 2019
  77. 0/3 format-patch: learn --cover-from-description optionDenton Liu, Oct 11, 2019
  78. 1/3 format-patch: remove erroneous and conditionDenton Liu, Oct 11, 2019
  79. 2/3 format-patch: use enum variablesDenton Liu, Oct 11, 2019
  80. Junio C HamanoOct 12, 2019
  81. 3/3 format-patch: teach --cover-from-description optionDenton Liu, Oct 11, 2019
  82. Junio C HamanoOct 12, 2019
  83. 4/3 fixup! format-patch: teach --cover-from-description optionDenton Liu, Oct 11, 2019
  84. Junio C HamanoOct 12, 2019
  85. 0/3 format-patch: learn --cover-from-description optionDenton Liu, Oct 14, 2019
  86. 1/3 format-patch: change erroneous and conditionDenton Liu, Oct 14, 2019
  87. Junio C HamanoOct 15, 2019
  88. Denton LiuOct 15, 2019
  89. 2/3 format-patch: use enum variablesDenton Liu, Oct 14, 2019
  90. 3/3 format-patch: teach --cover-from-description optionDenton Liu, Oct 14, 2019
  91. Junio C HamanoOct 15, 2019

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