Make unit tests runnable on macOS (#3018)

Author: gitccl

test/Makefile

@@ -21,6 +21,11 @@ include ../config.mk
 CPPFLAGS+=-DBTHREAD_USE_FAST_PTHREAD_MUTEX -D_GNU_SOURCE -DUSE_SYMBOLIZE -DNO_TCMALLOC -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS -DUNIT_TEST -Dprivate=public -Dprotected=public -DBVAR_NOT_LINK_DEFAULT_VARIABLES --include sstream_workaround.h
 CXXFLAGS+=$(CPPFLAGS) -pipe -Wall -W -fPIC -fstrict-aliasing -Wno-invalid-offsetof -Wno-unused-parameter -fno-omit-frame-pointer -std=c++0x
 
+# On Darwin, only gtest library is needed, other libraries have been linked in `brpc.dbg.dylib`
+ifeq ($(SYSTEM),Darwin)
+  GTEST_STATIC_LINKINGS := $(filter %libgtest.a %libgtest_main.a,$(STATIC_LINKINGS))
+endif
+
 #required by butil/crc32.cc to boost performance for 10x
 ifeq ($(shell test $(GCC_VERSION) -ge 40400; echo $$?),0)
   ifeq ($(shell uname -p),i386)  #note: i386 is processor family type, not the 32-bit x86 arch
@@ -210,7 +215,7 @@ test_butil:$(TEST_BUTIL_OBJS) | libbrpc.dbg.$(SOEXT)
 ifeq ($(SYSTEM),Linux)
 	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) -Xlinker "-(" $^ -Xlinker "-)" $(STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
 else ifeq ($(SYSTEM),Darwin)
-	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) $^ $(STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
+	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) $^ $(GTEST_STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
 endif
 
 test_bvar:libbvar.dbg.a $(TEST_BVAR_OBJS)
@@ -226,15 +231,15 @@ bthread%unittest:bthread%unittest.o | libbrpc.dbg.$(SOEXT)
 ifeq ($(SYSTEM),Linux)
 	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) -Xlinker "-(" $^ -Xlinker "-)" $(STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
 else ifeq ($(SYSTEM),Darwin)
-	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) $^ $(STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
+	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) $^ $(GTEST_STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
 endif
 
 brpc_%_unittest:$(TEST_PROTO_OBJS) brpc_%_unittest.o | libbrpc.dbg.$(SOEXT)
 	@echo "> Linking $@"
 ifeq ($(SYSTEM),Linux)
 	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) -Xlinker "-(" $^ -Xlinker "-)" $(STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
 else ifeq ($(SYSTEM),Darwin)
-	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) $^ $(STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
+	$(CXX) -o $@ $(LIBPATHS) $(SOPATHS) $^ $(GTEST_STATIC_LINKINGS) $(UT_DYNAMIC_LINKINGS)
 endif
 
 %.pb.cc %.pb.h:%.proto