Increase test coverage

[holgerd77]

Fixes #21 (partly) and #20

[axic]

How about merging this as is and creating a new PR for other tests?

[axic]

const getTests = exports.getTests = (testType, onFile, fileFilter = /.json$/, skipFn = () => {

It doesn't work on 4, I'm fine skipping that.

[coveralls]

Coverage increased (+8.06%) to 90.323% when pulling d99f8ac on increase-test-coverage into aba5c37 on master.

[holgerd77]

That's ok, will push asap.

[holgerd77]

@axic Ok, done.

Any insight on the getLength method? I know understand what it does, I have no imagination what it is used for though. Is this useful and does it make sense to include this in the API later on or should this be removed? I think it should be at least renamed to give more semantics on what it does.

So does it make sense to add tests for this respectively add the checks to existing tests?

[holgerd77]

@axic Had a linting error, pushed again.

[axic]

I think it tries to extract the size needed to encode the value? Not sure.