rails/rails — pull request #13670 by gmalette (2014-01-11 04:42:10+00:00)
Title: Allow filtering params based on parent keys

Some parameters on APIs have ambiguous names
that cannot be filtered altogether.

For example, it makes sense not to filter :code in

{ file: { code: '<% source %>' }}

It makes sense however to filter it in

{ credit_card: { code: '424242424242' }}

This PR allows the use of lambda to achieve such
results.