[PATCH 3/4] import: avoid uninitialized comparison on failures

[Eric Wong <e@80x24.org>]

readline may return undef when fast-import fails (as triggered
by t/lei-store-fail.t).  Ensure we give a more informative error
message in the syslog when this happens.  Arguably, having this
in the syslog when a client is connected via terminal is probably
not great, but perhaps unavoidable...
---
 lib/PublicInbox/Import.pm | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/PublicInbox/Import.pm b/lib/PublicInbox/Import.pm
index 2e193d46..ae46c5f4 100644
--- a/lib/PublicInbox/Import.pm
+++ b/lib/PublicInbox/Import.pm
@@ -152,8 +152,8 @@ sub progress {
 	my ($self, $msg) = @_;
 	my $io = $self->{io} or return;
 	print $io "progress $msg\n" or wfail;
-	readline($io) eq "progress $msg\n" or die
-		"progress $msg not received\n";
+	my $res = <$io> // die "EOF from fast-import progress $msg: $!";
+	$res eq "progress $msg\n" or die "BUG: `$res' != `progress $msg'";
 	undef;
 }