Get rid of magic numbers

test/cpp/end2end/grpclb_end2end_test.cc

@@ -890,15 +890,22 @@ TEST_F(UpdatesTest, UpdateBalancersDeadUpdate) {
 
 TEST_F(SingleBalancerTest, Drop) {
   const size_t kNumRpcsPerAddress = 100;
+  const int num_of_drop_by_rate_limiting_addresses = 1;
+  const int num_of_drop_by_load_balancing_addresses = 2;
+  const int num_of_drop_addresses = num_of_drop_by_rate_limiting_addresses +
+                                    num_of_drop_by_load_balancing_addresses;
+  const int num_total_addresses = num_backends_ + num_of_drop_addresses;
   ScheduleResponseForBalancer(
       0, BalancerServiceImpl::BuildResponseForBackends(
-             GetBackendPorts(), {{"rate_limiting", 1}, {"load_balancing", 2}}),
+             GetBackendPorts(),
+             {{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
+              {"load_balancing", num_of_drop_by_load_balancing_addresses}}),
       0);
   // Wait until all backends are ready.
   WaitForAllBackends();
   // Send kNumRpcsPerAddress RPCs for each server and drop address.
   size_t num_drops = 0;
-  for (size_t i = 0; i < kNumRpcsPerAddress * (num_backends_ + 3); ++i) {
+  for (size_t i = 0; i < kNumRpcsPerAddress * num_total_addresses; ++i) {
     EchoResponse response;
     const Status status = SendRpc(&response);
     if (!status.ok() &&
@@ -910,7 +917,7 @@ TEST_F(SingleBalancerTest, Drop) {
       EXPECT_EQ(response.message(), kMessage_);
     }
   }
-  EXPECT_EQ(kNumRpcsPerAddress * 3, num_drops);
+  EXPECT_EQ(kNumRpcsPerAddress * num_of_drop_addresses, num_drops);
 
   // Each backend should have gotten 100 requests.
   for (size_t i = 0; i < backends_.size(); ++i) {
@@ -925,9 +932,12 @@ TEST_F(SingleBalancerTest, Drop) {
 
 TEST_F(SingleBalancerTest, DropAllFirst) {
   // All registered addresses are marked as "drop".
+  const int num_of_drop_by_rate_limiting_addresses = 1;
+  const int num_of_drop_by_load_balancing_addresses = 1;
   ScheduleResponseForBalancer(
       0, BalancerServiceImpl::BuildResponseForBackends(
-             {}, {{"rate_limiting", 1}, {"load_balancing", 1}}),
+             {}, {{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
+                  {"load_balancing", num_of_drop_by_load_balancing_addresses}}),
       0);
   const Status status = SendRpc();
   EXPECT_FALSE(status.ok());
@@ -938,9 +948,12 @@ TEST_F(SingleBalancerTest, DropAll) {
   ScheduleResponseForBalancer(
       0, BalancerServiceImpl::BuildResponseForBackends(GetBackendPorts(), {}),
       0);
+  const int num_of_drop_by_rate_limiting_addresses = 1;
+  const int num_of_drop_by_load_balancing_addresses = 1;
   ScheduleResponseForBalancer(
       0, BalancerServiceImpl::BuildResponseForBackends(
-             {}, {{"rate_limiting", 1}, {"load_balancing", 1}}),
+             {}, {{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
+                  {"load_balancing", num_of_drop_by_load_balancing_addresses}}),
       1000);
 
   // First call succeeds.
@@ -996,20 +1009,27 @@ TEST_F(SingleBalancerWithClientLoadReportingTest, Vanilla) {
 
 TEST_F(SingleBalancerWithClientLoadReportingTest, Drop) {
   const size_t kNumRpcsPerAddress = 3;
+  const int num_of_drop_by_rate_limiting_addresses = 2;
+  const int num_of_drop_by_load_balancing_addresses = 1;
+  const int num_of_drop_addresses = num_of_drop_by_rate_limiting_addresses +
+                                    num_of_drop_by_load_balancing_addresses;
+  const int num_total_addresses = num_backends_ + num_of_drop_addresses;
   ScheduleResponseForBalancer(
       0, BalancerServiceImpl::BuildResponseForBackends(
-             GetBackendPorts(), {{"rate_limiting", 2}, {"load_balancing", 1}}),
+             GetBackendPorts(),
+             {{"rate_limiting", num_of_drop_by_rate_limiting_addresses},
+              {"load_balancing", num_of_drop_by_load_balancing_addresses}}),
       0);
   // Wait until all backends are ready.
   int num_warmup_ok = 0;
   int num_warmup_failure = 0;
   int num_warmup_drops = 0;
   std::tie(num_warmup_ok, num_warmup_failure, num_warmup_drops) =
-      WaitForAllBackends(num_backends_ + 3 /* num_requests_multiple_of */);
+      WaitForAllBackends(num_total_addresses /* num_requests_multiple_of */);
   const int num_total_warmup_requests =
       num_warmup_ok + num_warmup_failure + num_warmup_drops;
   size_t num_drops = 0;
-  for (size_t i = 0; i < kNumRpcsPerAddress * (num_backends_ + 3); ++i) {
+  for (size_t i = 0; i < kNumRpcsPerAddress * num_total_addresses; ++i) {
     EchoResponse response;
     const Status status = SendRpc(&response);
     if (!status.ok() &&
@@ -1021,7 +1041,7 @@ TEST_F(SingleBalancerWithClientLoadReportingTest, Drop) {
       EXPECT_EQ(response.message(), kMessage_);
     }
   }
-  EXPECT_EQ(kNumRpcsPerAddress * 3, num_drops);
+  EXPECT_EQ(kNumRpcsPerAddress * num_of_drop_addresses, num_drops);
   // Each backend should have gotten 100 requests.
   for (size_t i = 0; i < backends_.size(); ++i) {
     EXPECT_EQ(kNumRpcsPerAddress,
@@ -1035,10 +1055,10 @@ TEST_F(SingleBalancerWithClientLoadReportingTest, Drop) {
 
   const ClientStats client_stats = WaitForLoadReports();
   EXPECT_EQ(
-      kNumRpcsPerAddress * (num_backends_ + 3) + num_total_warmup_requests,
+      kNumRpcsPerAddress * num_total_addresses + num_total_warmup_requests,
       client_stats.num_calls_started);
   EXPECT_EQ(
-      kNumRpcsPerAddress * (num_backends_ + 3) + num_total_warmup_requests,
+      kNumRpcsPerAddress * num_total_addresses + num_total_warmup_requests,
       client_stats.num_calls_finished);
   EXPECT_EQ(0U, client_stats.num_calls_finished_with_client_failed_to_send);
   EXPECT_EQ(kNumRpcsPerAddress * num_backends_ + num_warmup_ok,
@@ -1046,7 +1066,8 @@ TEST_F(SingleBalancerWithClientLoadReportingTest, Drop) {
   // The number of warmup request is a multiple of the number of addresses.
   // Therefore, all addresses in the scheduled balancer response are hit the
   // same number of times.
-  const int num_times_drop_addresses_hit = num_warmup_drops / 3;
+  const int num_times_drop_addresses_hit =
+      num_warmup_drops / num_of_drop_addresses;
   EXPECT_THAT(
       client_stats.drop_token_counts,
       ::testing::ElementsAre(