Bugfix: _combiner is not initialized in IntRecorder constructor (#3066)

Author: chenBright

cmake/CMakeLists.download_gtest.in

@@ -20,7 +20,7 @@ project(googletest-download NONE)
 include(ExternalProject)
 ExternalProject_Add(googletest
   GIT_REPOSITORY    https://github.com/google/googletest.git
-  GIT_TAG           release-1.8.0
+  GIT_TAG           release-1.12.0
   SOURCE_DIR        "${PROJECT_BINARY_DIR}/googletest-src"
   BINARY_DIR        "${PROJECT_BINARY_DIR}/googletest-build"
   CONFIGURE_COMMAND ""

src/bvar/detail/combiner.h

@@ -172,7 +172,7 @@ friend class GlobalValue<self_type>;
             }
         }
 
-        void reset(const ElementTp& val, self_shared_type c) {
+        void reset(const ElementTp& val, const self_shared_type& c) {
             combiner = c;
             element.store(val);
         }

src/bvar/recorder.h

@@ -118,12 +118,12 @@ class IntRecorder : public Variable {
 
     IntRecorder() : _combiner(std::make_shared<combiner_type>()), _sampler(NULL) {}
 
-    explicit IntRecorder(const butil::StringPiece& name) : _sampler(NULL) {
+    explicit IntRecorder(const butil::StringPiece& name) : IntRecorder() {
         expose(name);
     }
 
     IntRecorder(const butil::StringPiece& prefix, const butil::StringPiece& name)
-        : _sampler(NULL) {
+        : IntRecorder() {
         expose_as(prefix, name);
     }
 

test/bvar_recorder_unittest.cpp

@@ -70,14 +70,19 @@ TEST(RecorderTest, sanity) {
         for (size_t i = 0; i < 100; ++i) {
             recorder << 2;
         }
-        ASSERT_EQ(2l, (int64_t)recorder.average());
+        ASSERT_EQ(2l, recorder.average());
         ASSERT_EQ("2", bvar::Variable::describe_exposed("var1"));
         std::vector<std::string> vars;
         bvar::Variable::list_exposed(&vars);
         ASSERT_EQ(1UL, vars.size());
         ASSERT_EQ("var1", vars[0]);
         ASSERT_EQ(1UL, bvar::Variable::count_exposed());
     }
+    {
+        bvar::IntRecorder recorder("var2");
+        recorder << 2;
+        ASSERT_EQ(2l, recorder.average());
+    }
     ASSERT_EQ(0UL, bvar::Variable::count_exposed());
 }