Add tracer sanity test

tools/run_tests/sanity/check_tracer_sanity.py

@@ -0,0 +1,54 @@
+#!/usr/bin/env python
+
+# 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.
+
+from __future__ import print_function
+
+import os
+import sys
+import re
+
+os.chdir(os.path.join(os.path.dirname(sys.argv[0]), '../../..'))
+
+errors = 0
+tracers = []
+pattern = re.compile("GRPC_TRACER_INITIALIZER\((true|false), \"(.*)\"\)")
+for root, dirs, files in os.walk('src/core'):
+  for filename in files:
+    path = os.path.join(root, filename)
+    if os.path.splitext(path)[1] != '.c': continue
+    with open(path) as f:
+      text = f.readlines()
+    for i in range(len(text)):
+      if "grpc_tracer_flag" in text[i]:
+        line = text[i].replace('\n', ' ')
+        j = i
+        while ";" not in text[j]:
+            j += 1
+            line += text[j].replace('\n', ' ')
+        if "GRPC_TRACER_INITIALIZER" not in line: continue
+        t = pattern.search(line).group(2)
+        if t not in tracers: tracers.append(t)
+
+with open('doc/environment_variables.md') as f:
+ text = f.read()
+
+for t in tracers:
+    if t not in text:
+        print("ERROR: tracer \"%s\" is not mentioned in doc/environment_variables.md" % t)
+        errors += 1
+
+
+assert errors == 0

tools/run_tests/sanity/sanity_tests.yaml

@@ -4,6 +4,7 @@
 - script: tools/run_tests/sanity/check_sources_and_headers.py
 - script: tools/run_tests/sanity/check_submodules.sh
 - script: tools/run_tests/sanity/check_test_filtering.py
+- script: tools/run_tests/sanity/check_tracer_sanity.py
 - script: tools/run_tests/sanity/core_banned_functions.py
 - script: tools/buildgen/generate_projects.sh -j 3
   cpu_cost: 3