This is a known issue and can be fixed by using custom frameworks for testing. https://shadabanwer.wordpress.com/2013/06/14/map-unit-test-does-not-work-in-biztalk-2013-because-testablemapbase-class-is-not-correct/
Marked as answer byMark BrimbleFriday, August 25, 2017 8:38 PM
This is a known issue and can be fixed by using custom frameworks for testing. https://shadabanwer.wordpress.com/2013/06/14/map-unit-test-does-not-work-in-biztalk-2013-because-testablemapbase-class-is-not-correct/
Marked as answer byMark BrimbleFriday, August 25, 2017 8:38 PM