Add a flag to the resolver_component_test that permits extra addresses

test/cpp/naming/resolver_component_test.cc

@@ -65,6 +65,11 @@ DEFINE_string(expected_addrs, "",
               "List of expected backend or balancer addresses in the form "
               "'<ip0:port0>,<is_balancer0>;<ip1:port1>,<is_balancer1>;...'. "
               "'is_balancer' should be bool, i.e. true or false.");
+DEFINE_bool(allow_extra_addrs, false,
+            "Permit extra resolved addresses in the final list of "
+            "resolved addresses. This is useful in certain integration "
+            "test environments in which DNS responses are not fully "
+            "deterministic.");
 DEFINE_string(expected_chosen_service_config, "",
               "Expected service config json string that gets chosen (no "
               "whitespace). Empty for none.");
@@ -240,9 +245,11 @@ void CheckResolverResultLocked(void* argsp, grpc_error* err) {
   GPR_ASSERT(channel_arg->type == GRPC_ARG_POINTER);
   grpc_lb_addresses* addresses =
       (grpc_lb_addresses*)channel_arg->value.pointer.p;
-  gpr_log(GPR_INFO, "num addrs found: %" PRIdPTR ". expected %" PRIdPTR,
-          addresses->num_addresses, args->expected_addrs.size());
-  GPR_ASSERT(addresses->num_addresses == args->expected_addrs.size());
+  gpr_log(GPR_INFO,
+          "num addrs found: %" PRIdPTR ". expected %" PRIdPTR
+          ". Allow extra addresses:%d.",
+          addresses->num_addresses, args->expected_addrs.size(),
+          FLAGS_allow_extra_addrs);
   std::vector<GrpcLBAddress> found_lb_addrs;
   for (size_t i = 0; i < addresses->num_addresses; i++) {
     grpc_lb_address addr = addresses->addresses[i];
@@ -254,13 +261,20 @@ void CheckResolverResultLocked(void* argsp, grpc_error* err) {
     gpr_free(str);
   }
   if (args->expected_addrs.size() != found_lb_addrs.size()) {
-    gpr_log(GPR_DEBUG,
-            "found lb addrs size is: %" PRIdPTR
-            ". expected addrs size is %" PRIdPTR,
-            found_lb_addrs.size(), args->expected_addrs.size());
-    abort();
+    // Permit extra resolved addresses if "--allow_extra_addrs" was set.
+    if (!(FLAGS_allow_extra_addrs &&
+          found_lb_addrs.size() > args->expected_addrs.size())) {
+      gpr_log(GPR_DEBUG,
+              "found lb addrs size is: %" PRIdPTR
+              ". expected addrs size is %" PRIdPTR ". --allow_extra_addrs=%d.",
+              found_lb_addrs.size(), args->expected_addrs.size(),
+              FLAGS_allow_extra_addrs);
+      abort();
+    }
+  }
+  for (size_t i = 0; i < args->expected_addrs.size(); i++) {
+    EXPECT_THAT(found_lb_addrs, ::testing::Contains(args->expected_addrs[i]));
   }
-  EXPECT_THAT(args->expected_addrs, UnorderedElementsAreArray(found_lb_addrs));
   CheckServiceConfigResultLocked(channel_args, args);
   if (args->expected_service_config_string == "") {
     CheckLBPolicyResultLocked(channel_args, args);