Add stats test

1 files changed, 127 insertions, 0 deletions

diff --git a/test/core/debug/stats_test.cc b/test/core/debug/stats_test.cc
new file mode 100644
index 0000000000..65ccc7a5c8
--- /dev/null
+++ b/test/core/debug/stats_test.cc
@@ -0,0 +1,127 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+extern "C" {
+#include "src/core/lib/debug/stats.h"
+}
+
+#include <grpc/grpc.h>
+#include <grpc/support/log.h>
+#include <gtest/gtest.h>
+
+namespace grpc {
+namespace testing {
+
+class Snapshot {
+ public:
+  Snapshot() { grpc_stats_collect(&begin_); }
+
+  grpc_stats_data delta() {
+    grpc_stats_data now;
+    grpc_stats_collect(&now);
+    grpc_stats_data delta;
+    grpc_stats_diff(&now, &begin_, &delta);
+    return delta;
+  }
+
+ private:
+  grpc_stats_data begin_;
+};
+
+TEST(StatsTest, IncCounters) {
+  for (int i = 0; i < GRPC_STATS_COUNTER_COUNT; i++) {
+    Snapshot snapshot;
+
+    grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+    GRPC_STATS_INC_COUNTER(&exec_ctx, (grpc_stats_counters)i);
+    grpc_exec_ctx_finish(&exec_ctx);
+
+    EXPECT_EQ(snapshot.delta().counters[i], 1);
+  }
+}
+
+TEST(StatsTest, IncSpecificCounter) {
+  Snapshot snapshot;
+
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  GRPC_STATS_INC_SYSCALL_POLL(&exec_ctx);
+  grpc_exec_ctx_finish(&exec_ctx);
+
+  EXPECT_EQ(snapshot.delta().counters[GRPC_STATS_COUNTER_SYSCALL_POLL], 1);
+}
+
+static int FindExpectedBucket(int i, int j) {
+  if (j < 0) {
+    return 0;
+  }
+  if (j >=
+      grpc_stats_histo_bucket_boundaries[i][grpc_stats_histo_buckets[i] - 1]) {
+    return grpc_stats_histo_buckets[i] - 1;
+  }
+  int r = 0;
+  while (grpc_stats_histo_bucket_boundaries[i][r + 1] <= j) r++;
+  return r;
+}
+
+static int FindNonZeroBucket(const grpc_stats_data& data, int i) {
+  for (int j = 0; j < grpc_stats_histo_buckets[i]; j++) {
+    if (data.histograms[grpc_stats_histo_start[i] + j] != 0) {
+      return j;
+    }
+  }
+  return -1;
+}
+
+TEST(StatsTest, IncHistogram) {
+  for (int i = 0; i < GRPC_STATS_HISTOGRAM_COUNT; i++) {
+    for (int j = -1000;
+         j <
+         grpc_stats_histo_bucket_boundaries[i]
+                                           [grpc_stats_histo_buckets[i] - 1] +
+             1000;
+         j++) {
+      gpr_log(GPR_DEBUG, "histo:%d value:%d", i, j);
+
+      Snapshot snapshot;
+
+      int expected_bucket = FindExpectedBucket(i, j);
+
+      grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+      grpc_stats_inc_histogram[i](&exec_ctx, j);
+      grpc_exec_ctx_finish(&exec_ctx);
+
+      auto delta = snapshot.delta();
+      int got_bucket = FindNonZeroBucket(delta, i);
+
+      EXPECT_EQ(expected_bucket, got_bucket);
+      EXPECT_EQ(delta.histograms[grpc_stats_histo_start[i] + expected_bucket],
+                1);
+    }
+  }
+}
+
+}  // namespace testing
+}  // namespace grpc
+
+int main(int argc, char** argv) {
+  ::testing::InitGoogleTest(&argc, argv);
+  grpc_init();
+  int ret = RUN_ALL_TESTS();
+  grpc_shutdown();
+  return ret;
+}