Safer argument parsing

[bobjflong]

An issue I've seen crop up is that if a global key is set (which most of your docs use), and then client API keys are used (eg. if using OAuth), then unexpected results can happen. This includes loading customer data from the parent global key.

> require 'stripe'

> Stripe.api_key = "sk_test_foo"
=> "sk_test_foo"

> Stripe::Customer.all
# => loads customers from the global key

> Stripe::Customer.all({}, { api_key: nil })
# => ALSO loads customers from the global key!!

With my changes:

> Stripe::Customer.all({}, { api_key: nil })
TypeError: api_key must be a String

[russelldavis]

This change seems unnecessary. Tests pass without it.

[russelldavis]

@bobjflong Thanks for the pull request! I like the extra safety this provides. I left a few comments about changing the approach a bit; other than that I'll be happy to merge this.

[bobjflong]

thanks @russelldavis made a bunch of changes based on your feedback

[russelldavis]

What do you think about just getting rid of this when NilClass clause altogether and letting the else clause handle it? (In which case you could also merge raise_bad_api_key into check_bad_api_key, since that would be the only place it's used.)

[bobjflong]

Great catch, fixed

[russelldavis]

Github says there are conflicts that need to be resolved -- can you rebase against master and resolve those?

[bobjflong]

Huh weird. Will do tomorrow

[bobjflong]

Ugh seems like my local files were super out of date. Going to replay my changes in a new pr.