add test case to test whether CrossPlatform::getenv_safe can find a k…

…nown existing env var

OdbDesignTests/CrossPlatformTests.cpp

@@ -4,6 +4,8 @@
 #include "Fixtures/TestDataFixture.h"
 #include <string>
 #include <filesystem>
+#include <gmock/gmock-matchers.h>
+#include <cstdlib>
 
 using namespace std::filesystem;
 using namespace Odb::Test::Fixtures;
@@ -14,15 +16,34 @@ namespace Odb::Test
 {
 	TEST_F(TestDataFixture, Test_CrossPlatform_GetEnvSafe_VariableExists)
 	{
+		auto szTestEnvValue = std::getenv(ODB_TEST_ENV_NAME);
+		EXPECT_THAT(szTestEnvValue, NotNull());
+
 		std::string value;
 		ASSERT_EQ(value.size(), 0U);
-		ASSERT_TRUE(CrossPlatform::getenv_safe(ODB_TEST_ENV_NAME, value));
+		auto bResult = CrossPlatform::getenv_safe(ODB_TEST_ENV_NAME, value);
 		ASSERT_STRNE(value.c_str(), "");
 		ASSERT_STREQ(value.c_str(), ODB_TEST_ENV_VALUE);
+		ASSERT_TRUE(bResult);
+	}
+
+	TEST_F(TestDataFixture, Test_CrossPlatform_GetEnvSafe_KnownVariableExists)
+	{
+		auto szTestEnvValue = std::getenv(ODB_TEST_DATA_DIR_ENV_NAME);
+		EXPECT_THAT(szTestEnvValue, NotNull());
+
+		std::string value;
+		ASSERT_EQ(value.size(), 0U);
+		auto bResult = CrossPlatform::getenv_safe(ODB_TEST_DATA_DIR_ENV_NAME, value);
+		ASSERT_STRNE(value.c_str(), "");		
+		ASSERT_TRUE(bResult);
 	}
 
 	TEST_F(TestDataFixture, Test_CrossPlatform_GetEnvSafe_VariableDoesntExist)
 	{
+		auto szDoesntExistVal = std::getenv(ODB_TEST_NONEXISTENT_ENV_NAME);
+		EXPECT_THAT(szDoesntExistVal, IsNull());
+
 		std::string value;
 		ASSERT_EQ(value.size(), 0U);
 		ASSERT_FALSE(CrossPlatform::getenv_safe(ODB_TEST_NONEXISTENT_ENV_NAME, value));