Introduce GoogleTest C++ unit testing framework

tests/src/test1.cpp

@@ -0,0 +1,19 @@
+#include "gtest/gtest.h"
+
+TEST(FirstSuite, FirstTest){
+    EXPECT_NE(1, 1) << "are in fact equal";
+}
+
+TEST(FirstSuite, SecondTest){
+    EXPECT_EQ(1, 2) << "not equal";
+}
+
+TEST(FirstSuite, ThirdTest){
+    ASSERT_STREQ("A", "A") << "str not equal";
+}
+TEST(FirstSuite,FifthTest){
+    ASSERT_STRNE("am", "am") << "str equal";
+}
+TEST(FirstSuite, FourthTest){
+    ASSERT_STREQ("am", "A") << "str not equal";
+}