There should be no reason for any code changes with the new Sinon 6. Usually,
MAJOR releases should come with breaking changes, but there are no known breaking changes in
sinon@6 at the time of this writing. We chose to release a new major version as a pragmatic solution to some noise related to releasing Sinon 5.1, which featured some breaking changes related to ESM (which since has been resolved).
If you should experience any issues moving from Sinon 5 to Sinon 6, please let us know!.