Add nil value check

Signed-off-by: leo-ma <begeekmyfriend@gmail.com>
Merge remote-tracking branch 'origin/lua-nil-bug-fix' into test-framework
Seperate test cases and test methods

Signed-off-by: leo-ma <begeekmyfriend@gmail.com>
Seperate test case from framework

Signed-off-by: leo-ma <begeekmyfriend@gmail.com>
Rename

Signed-off-by: leo-ma <begeekmyfriend@gmail.com>