Params.fetch covers up any KeyError raised in block.

[d-Pixie]

What?

Given:

params = ActionController::Parameters.new()
params.fetch(:missing_key) { some.default_action( :that_raises, KeyError ) }

I would expect to see the KeyError from the block, not a ActionController::ParameterMissing exception for :missing_key.

Why?

To ease in debugging one should not cover relevant exceptions. In this case the error is not that the requested key is missing and therefore the presented error message is a lie :)

Fix

Not implemented yet, I wanted to get some comments before coding this time. I'd guess we'd have to fix the rescue line in action_controller/parameters.rb line 83. Suggestions on how are welcome.

If this is something we want just let me know and I'll fix it.

[thomasfedb]

@d-Pixie I think this needs to be fixed. Are you prepared to make the changes of should I?

[d-Pixie]

I'll write a proposal patch today ...

[rafaelfranca]

Any changes for this code should be submitted first to rails/rails.

[d-Pixie]

@rafaelfranca - The patch is now available as a pull request in rails/rails. If/when accepted I'll backport it here ...

[d-Pixie]

@thomasfedb - The code is in, comments are welcome.

[ClayShentrup]

This is still broken.