log: add log.showSignature configuration variable

Users may want to always use "--show-signature" while using git-log and
related commands.

When log.showSignature is set to true, git-log and related commands will
behave as if "--show-signature" was given to them.

Note that this config variable is meant to affect git-log, git-show,
git-whatchanged and git-reflog. Other commands like git-format-patch,
git-rev-list are not to be affected by this config variable.

Signed-off-by: Mehul Jain <mehul.jain2029@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-log.txt

@@ -198,6 +198,10 @@ log.showRoot::
 	`git log -p` output would be shown without a diff attached.
 	The default is `true`.
 
+log.showSignature::
+	If `true`, `git log` and related commands will act as if the
+	`--show-signature` option was passed to them.
+
 mailmap.*::
 	See linkgit:git-shortlog[1].
 

builtin/log.c

@@ -33,6 +33,7 @@ static const char *default_date_mode = NULL;
 static int default_abbrev_commit;
 static int default_show_root = 1;
 static int default_follow;
+static int default_show_signature;
 static int decoration_style;
 static int decoration_given;
 static int use_mailmap_config;
@@ -119,6 +120,7 @@ static void cmd_log_init_defaults(struct rev_info *rev)
 	rev->abbrev_commit = default_abbrev_commit;
 	rev->show_root_diff = default_show_root;
 	rev->subject_prefix = fmt_patch_subject_prefix;
+	rev->show_signature = default_show_signature;
 	DIFF_OPT_SET(&rev->diffopt, ALLOW_TEXTCONV);
 
 	if (default_date_mode)
@@ -409,6 +411,10 @@ static int git_log_config(const char *var, const char *value, void *cb)
 		use_mailmap_config = git_config_bool(var, value);
 		return 0;
 	}
+	if (!strcmp(var, "log.showsignature")) {
+		default_show_signature = git_config_bool(var, value);
+		return 0;
+	}
 
 	if (grep_config(var, value, cb) < 0)
 		return -1;

t/t4202-log.sh

@@ -898,6 +898,26 @@ test_expect_success GPG '--no-show-signature overrides --show-signature' '
 	! grep "^gpg:" actual
 '
 
+test_expect_success GPG 'log.showsignature=true behaves like --show-signature' '
+	test_config log.showsignature true &&
+	git log -1 signed >actual &&
+	grep "gpg: Signature made" actual &&
+	grep "gpg: Good signature" actual
+'
+
+test_expect_success GPG '--no-show-signature overrides log.showsignature=true' '
+	test_config log.showsignature true &&
+	git log -1 --no-show-signature signed >actual &&
+	! grep "^gpg:" actual
+'
+
+test_expect_success GPG '--show-signature overrides log.showsignature=false' '
+	test_config log.showsignature false &&
+	git log -1 --show-signature signed >actual &&
+	grep "gpg: Signature made" actual &&
+	grep "gpg: Good signature" actual
+'
+
 test_expect_success 'log --graph --no-walk is forbidden' '
 	test_must_fail git log --graph --no-walk
 '

t/t7510-signed-commit.sh

@@ -210,4 +210,11 @@ test_expect_success GPG 'show lack of signature with custom format' '
 	test_cmp expect actual
 '
 
+test_expect_success GPG 'log.showsignature behaves like --show-signature' '
+	test_config log.showsignature true &&
+	git show initial >actual &&
+	grep "gpg: Signature made" actual &&
+	grep "gpg: Good signature" actual
+'
+
 test_done