perl tap: Show failed command output

Capture stdout and stderr from command_ok() and command_fails() and emit
them as TAP diagnostics on failure.  Output is truncated to the first
and last 30 lines per channel to avoid flooding.

A new helper _diag_command_output() is introduced in Utils.pm so
both functions share the same truncation and formatting logic.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Zsolt Parragi <zsolt.parragi@percona.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/DFYFWM053WHS.10K8ZPJ605UFK@jeltef.nl

diff --git a/src/bin/pg_ctl/t/001_start_stop.pl b/src/bin/pg_ctl/t/001_start_stop.pl
index 9b79de319f2ac0fba50febaf964c2d34333b062d..4a25b35ed9ca4ec2dd1fd45e602992b6ff4f66f5 100644 (file)
--- a/src/bin/pg_ctl/t/001_start_stop.pl
+++ b/src/bin/pg_ctl/t/001_start_stop.pl
@@ -112,7 +112,7 @@ SKIP:
        ok(check_mode_recursive("$tempdir/data", 0750, 0640));
 }
 
-command_ok([ 'pg_ctl', 'restart', '--pgdata' => "$tempdir/data" ],
+command_ok([ 'pg_ctl', 'restart', '--pgdata' => "$tempdir/data", '--log' => $logFileName ],
        'pg_ctl restart with server running');
 
 system_or_bail 'pg_ctl', 'stop', '--pgdata' => "$tempdir/data";

diff --git a/src/test/perl/PostgreSQL/Test/Utils.pm b/src/test/perl/PostgreSQL/Test/Utils.pm
index ff843eecc6eb4bb08226cc555d98a12d3a27f04c..b781d76a98bfb2925981cfb07e712bd6ed49e053 100644 (file)
--- a/src/test/perl/PostgreSQL/Test/Utils.pm
+++ b/src/test/perl/PostgreSQL/Test/Utils.pm
@@ -937,6 +937,35 @@ sub dir_symlink
        die "No $newname" unless -e $newname;
 }
 
+# Log command output. Truncates to first/last 30 lines if over 60 lines.
+sub _diag_command_output
+{
+       my ($cmd, $stdout, $stderr) = @_;
+
+       diag(join(" ", @$cmd));
+
+       for my $channel (['stdout', $stdout], ['stderr', $stderr])
+       {
+               my ($name, $output) = @$channel;
+               next unless $output;
+
+               diag("-------------- $name --------------");
+               my @lines = split /\n/, $output;
+               if (@lines > 60)
+               {
+                       diag(join("\n", @lines[0 .. 29]));
+                       diag("... " . (@lines - 60) . " lines omitted ...");
+                       diag(join("\n", @lines[-30 .. -1]));
+               }
+               else
+               {
+                       diag($output);
+               }
+       }
+
+       diag("------------------------------------");
+}
+
 =pod
 
 =back
@@ -947,7 +976,7 @@ sub dir_symlink
 
 =item command_ok(cmd, test_name)
 
-Check that the command runs (via C<run_log>) successfully.
+Check that the command runs successfully.
 
 =cut
 
@@ -955,8 +984,14 @@ sub command_ok
 {
        local $Test::Builder::Level = $Test::Builder::Level + 1;
        my ($cmd, $test_name) = @_;
-       my $result = run_log($cmd);
-       ok($result, $test_name);
+       my ($stdout, $stderr);
+       print("# Running: " . join(" ", @{$cmd}) . "\n");
+       my $result = IPC::Run::run $cmd, '>' => \$stdout, '2>' => \$stderr;
+       ok($result, $test_name) or do
+       {
+               diag("---------- command failed ----------");
+               _diag_command_output($cmd, $stdout, $stderr);
+       };
        return;
 }
 
@@ -964,7 +999,7 @@ sub command_ok
 
 =item command_fails(cmd, test_name)
 
-Check that the command fails (when run via C<run_log>).
+Check that the command fails.
 
 =cut
 
@@ -972,8 +1007,14 @@ sub command_fails
 {
        local $Test::Builder::Level = $Test::Builder::Level + 1;
        my ($cmd, $test_name) = @_;
-       my $result = run_log($cmd);
-       ok(!$result, $test_name);
+       my ($stdout, $stderr);
+       print("# Running: " . join(" ", @{$cmd}) . "\n");
+       my $result = IPC::Run::run $cmd, '>' => \$stdout, '2>' => \$stderr;
+       ok(!$result, $test_name) or do
+       {
+               diag("-- command succeeded unexpectedly --");
+               _diag_command_output($cmd, $stdout, $stderr);
+       };
        return;
 }