Handle whitespace after floats in test fields

Broken in 9bb8f962.
Committed solution proposed by phk@, discussed with phk@ and martin@.

Fixes #1845.

bin/varnishtest/tests/l00001.vtc

@@ -151,6 +151,12 @@ logexpect l1 -d 1 -g vxid -q "RespHeader[2] == 123" {
 	  expect * =	End
 } -run
 
+# Test field on floats
+logexpect l1 -d 1 -g vxid -q "RespHeader[2] == 123." {
+	  expect 0 *	Begin	req
+	  expect * =	End
+} -run
+
 # Test taglists
 logexpect l1 -d 1 -g vxid -q "Debug,Resp* == 200" {
 	  expect 0 *	Begin	req

lib/libvarnishapi/vsl_query.c

@@ -78,7 +78,7 @@ vslq_test_rec(const struct vex *vex, const struct VSLC_ptr *rec)
 	const struct vex_rhs *rhs;
 	long long lhs_int = 0;
 	double lhs_float = 0.;
-	const char *b, *e;
+	const char *b, *e, *q;
 	char *p;
 	int i;
 
@@ -145,9 +145,11 @@ vslq_test_rec(const struct vex *vex, const struct VSLC_ptr *rec)
 			/* Can't parse - no match */
 			return (0);
 		case VEX_FLOAT:
-			lhs_float = VNUM(b);
+			lhs_float = VNUMpfx(b, &q);
 			if (isnan(lhs_float))
 				return (0);
+			if (q != NULL && q > p && !isspace(q[-1]))
+				return (0);
 			break;
 		default:
 			WRONG("Wrong RHS type");