Overview

Currently the utils don't provide a way to remove hyphens from a valid ISBN (10 or 13), without also converting them.

The use case is:
Given an ISBN, validate and convert to ISBN 13 w/o hyphens.

• if a valid ISBN 10, convert to an ISBN 13 w/o hyphens

• if a valid ISBN 13, return the ISBN 13 w/o hyphens

The convertTo13DigitNumber(String) function only accepts valid ISBN 10s. Anything else (including a valid ISBN 13) will give you null.

The ability to insert hyphens already exists with the insertHyphens(String) method. We should have a corresponding removeHyphens(String) method.

Acceptance Criteria

• the ability to explicitly remove hyphens from either a 10 or 13 digit ISBN has been added

• unit tests are updated

• a new version of the utils has been released (v1.1.1?)