Merge branch 'jk/push-progress'

* jk/push-progress:
  push: pass --progress down to git-pack-objects
  t5523-push-upstream: test progress messages
  t5523-push-upstream: add function to ensure fresh upstream repo
  test_terminal: ensure redirections work reliably
  test_terminal: catch use without TTY prerequisite
  test-lib: allow test code to check the list of declared prerequisites
  tests: test terminal output to both stdout and stderr
  tests: factor out terminal handling from t7006

t/test-terminal.perl

@@ -0,0 +1,76 @@
+#!/usr/bin/perl
+use 5.008;
+use strict;
+use warnings;
+use IO::Pty;
+use File::Copy;
+
+# Run @$argv in the background with stdio redirected to $out and $err.
+sub start_child {
+	my ($argv, $out, $err) = @_;
+	my $pid = fork;
+	if (not defined $pid) {
+		die "fork failed: $!"
+	} elsif ($pid == 0) {
+		open STDOUT, ">&", $out;
+		open STDERR, ">&", $err;
+		close $out;
+		exec(@$argv) or die "cannot exec '$argv->[0]': $!"
+	}
+	return $pid;
+}
+
+# Wait for $pid to finish.
+sub finish_child {
+	# Simplified from wait_or_whine() in run-command.c.
+	my ($pid) = @_;
+
+	my $waiting = waitpid($pid, 0);
+	if ($waiting < 0) {
+		die "waitpid failed: $!";
+	} elsif ($? & 127) {
+		my $code = $? & 127;
+		warn "died of signal $code";
+		return $code - 128;
+	} else {
+		return $? >> 8;
+	}
+}
+
+sub xsendfile {
+	my ($out, $in) = @_;
+
+	# Note: the real sendfile() cannot read from a terminal.
+
+	# It is unspecified by POSIX whether reads
+	# from a disconnected terminal will return
+	# EIO (as in AIX 4.x, IRIX, and Linux) or
+	# end-of-file.  Either is fine.
+	copy($in, $out, 4096) or $!{EIO} or die "cannot copy from child: $!";
+}
+
+sub copy_stdio {
+	my ($out, $err) = @_;
+	my $pid = fork;
+	defined $pid or die "fork failed: $!";
+	if (!$pid) {
+		close($out);
+		xsendfile(\*STDERR, $err);
+		exit 0;
+	}
+	close($err);
+	xsendfile(\*STDOUT, $out);
+	finish_child($pid) == 0
+		or exit 1;
+}
+
+if ($#ARGV < 1) {
+	die "usage: test-terminal program args";
+}
+my $master_out = new IO::Pty;
+my $master_err = new IO::Pty;
+my $pid = start_child(\@ARGV, $master_out->slave, $master_err->slave);
+close $master_out->slave;
+close $master_err->slave;
+copy_stdio($master_out, $master_err);
+exit(finish_child($pid));