Trivial test-case for conditional fetch

bin/varnishtest/tests/b00039.vtc

+varnishtest "Test IMS"
+
+server s1 {
+	rxreq
+	txresp -hdr "Last-Modified: Wed, 11 Sep 2013 13:36:55 GMT" -body "Geoff Rules"
+	rxreq
+	expect req.http.if-modified-since == "Wed, 11 Sep 2013 13:36:55 GMT"
+	txresp -status 304
+} -start
+
+varnish v1 -vcl+backend {
+	sub vcl_backend_response {
+		set beresp.ttl = 2s;
+		set beresp.grace = 20s;
+		set beresp.keep = 1m;
+	}
+} -start
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.status == 200
+	expect resp.body == "Geoff Rules"
+} -run
+
+delay 3
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.status == 200
+	expect resp.body == "Geoff Rules"
+} -run
+
+client c1 {
+	txreq
+	rxresp
+	expect resp.status == 200
+	expect resp.body == "Geoff Rules"
+} -run