new file mode 100644
--- /dev/null
+++ b/proxy_unfinished.t
@@ -0,0 +1,169 @@
+#!/usr/bin/perl
+
+# (C) Maxim Dounin
+
+# Tests for http proxy and prematurely closed connections.  Incomplete
+# responses shouldn't loose information about their incompleteness.
+
+# In particular, incomplete responses:
+#
+# - shouldn't be cached
+#
+# - if a response is sent using chunked transfer encoding, 
+#   final chunk shouldn't be sent
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+use Socket qw/ CRLF /;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+plan(skip_all => 'win32') if $^O eq 'MSWin32';
+
+my $t = Test::Nginx->new()->has(qw/http proxy cache sub/)->plan(4)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    proxy_cache_path   %%TESTDIR%%/cache  levels=1:2
+                       keys_zone=one:1m;
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        location / {
+            sub_filter foo bar;
+            sub_filter_types *;
+            proxy_pass http://127.0.0.1:8081;
+        }
+
+        location /cache/ {
+            proxy_pass http://127.0.0.1:8081/;
+            proxy_cache one;
+        }
+    }
+}
+
+EOF
+
+$t->run_daemon(\&http_daemon);
+$t->run()->waitforsocket('127.0.0.1:8081');
+
+###############################################################################
+
+my ($r, $n);
+
+$r = http_get('/cache/length');
+$r =~ m/unfinished (\d+)/; $n = $1 + 1;
+like(http_get('/cache/length'), qr/unfinished $n/, 'unfinished not cached');
+
+TODO: {
+local $TODO = 'not yet';
+
+# chunked encoding has enough information to don't cache a response,
+# much like with Content-Length available
+
+$r = http_get('/cache/chunked');
+$r =~ m/unfinished (\d+)/; $n = $1 + 1;
+like(http_get('/cache/chunked'), qr/unfinished $n/, 'unfinished chunked');
+
+}
+
+TODO: {
+local $TODO = 'not yet';
+
+# make sure there is no final chunk in normal responses
+
+like(http_get_11('/length'), qr/unfinished(?!.*\x0d\x0a?0\x0d\x0a?)/s,
+	'length no final chunk');
+like(http_get_11('/chunked'), qr/unfinished(?!.*\x0d\x0a?0\x0d\x0a?)/s,
+	'chunked no final chunk');
+
+}
+
+###############################################################################
+
+sub http_get_11 {
+	my ($uri) = @_;
+
+	return http(
+		"GET $uri HTTP/1.1" . CRLF .
+		"Connection: close" . CRLF .
+		"Host: localhost" . CRLF . CRLF
+	);
+}
+
+###############################################################################
+
+sub http_daemon {
+	my $server = IO::Socket::INET->new(
+		Proto => 'tcp',
+		LocalAddr => '127.0.0.1:8081',
+		Listen => 5,
+		Reuse => 1
+	)
+		or die "Can't create listening socket: $!\n";
+
+	local $SIG{PIPE} = 'IGNORE';
+
+	my $num = 0;
+
+	while (my $client = $server->accept()) {
+		$client->autoflush(1);
+
+		my $headers = '';
+		my $uri = '';
+
+		while (<$client>) {
+			$headers .= $_;
+			last if (/^\x0d?\x0a?$/);
+		}
+
+		$uri = $1 if $headers =~ /^\S+\s+([^ ]+)\s+HTTP/i;
+		$num++;
+
+		if ($uri eq '/length') {
+			print $client
+				"HTTP/1.1 200 OK" . CRLF .
+				"Content-Length: 100" . CRLF .
+				"Cache-Control: max-age=300" . CRLF .
+				"Connection: close" . CRLF .
+				CRLF .
+				"unfinished $num" . CRLF;
+
+		} elsif ($uri eq '/chunked') {
+			print $client
+				"HTTP/1.1 200 OK" . CRLF .
+				"Transfer-Encoding: chunked" . CRLF .
+				"Cache-Control: max-age=300" . CRLF .
+				"Connection: close" . CRLF .
+				CRLF .
+				"ff" . CRLF .
+				"unfinished $num" . CRLF;
+		}
+	}
+}
+
+###############################################################################