Bowling Challenge: Review Guidelines

Style

Lines no longer than 80 characters
Short methods
Descriptively named methods. Function names should ideally start with a verb so it's clear that they do something to something else.
Methods have a single responsibility
Appropriate semi-colon use
No nested conditionals
Code free of unnecessary comments and commented-out sections
Consistent indentation

Testing

Do the tests pass?
Is master clean? (does the code work as is?)
Tests organized under appropriate describe blocks.
Are the tests descriptive?
Are the tests DRY? (are they repeating themselves in the test in way that could be extracted)
Is there any state being persisted between tests?
Have they tested edge cases? Many solutions rely on a 'virtuous consumer' - i.e. they do not validate inputs or check for out of range values etc.

OOP

Are your objects solid?
- Have you separated responsibilities of...
  - knowing whether a frame is a strike / spare
  - keeping track of the progress of a game
  - calculating bonuses
Reliance on implementation details. It's common to see objects relying on the internals of other objects or their implementation of low-level types (particularly arrays).

Design

Have they met the specification? Have they actually modelled the scoring of bowling?
Is it overly complicated? (what's your gut feeling)