perf/aggregate: add --reponame option

This makes it easier to use the aggregate script
on the command line when one wants to get the
"environment" fields set in the codespeed output.

Previously setting GIT_REPO_NAME was needed
for this purpose.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/perf/aggregate.perl

@@ -37,7 +37,7 @@ sub format_times {
 }
 
 my (@dirs, %dirnames, %dirabbrevs, %prefixes, @tests,
-    $codespeed, $subsection);
+    $codespeed, $subsection, $reponame);
 while (scalar @ARGV) {
 	my $arg = $ARGV[0];
 	my $dir;
@@ -55,6 +55,15 @@ while (scalar @ARGV) {
 		}
 		next;
 	}
+	if ($arg eq "--reponame") {
+		shift @ARGV;
+		$reponame = $ARGV[0];
+		shift @ARGV;
+		if (! $reponame) {
+			die "empty reponame";
+		}
+		next;
+	}
 	last if -f $arg or $arg eq "--";
 	if (! -d $arg) {
 		my $rev = Git::command_oneline(qw(rev-parse --verify), $arg);
@@ -210,7 +219,9 @@ sub print_codespeed_results {
 	}
 
 	my $environment;
-	if (exists $ENV{GIT_PERF_REPO_NAME} and $ENV{GIT_PERF_REPO_NAME} ne "") {
+	if ($reponame) {
+		$environment = $reponame;
+	} elsif (exists $ENV{GIT_PERF_REPO_NAME} and $ENV{GIT_PERF_REPO_NAME} ne "") {
 		$environment = $ENV{GIT_PERF_REPO_NAME};
 	} elsif (exists $ENV{GIT_TEST_INSTALLED} and $ENV{GIT_TEST_INSTALLED} ne "") {
 		$environment = $ENV{GIT_TEST_INSTALLED};