Scratch

After seeing a presentation (by Gary Haran) on Rails engines and reading a certain blog post, I decided that enough was enough! I had some Rails induced itches that needed some much needed relief. Thus here is Scratch, a library which tries to fix a bunch of Rails' most insignificant shortcomings.

• The normalize model mixin
• A few core extensions

Simply add Scratch to your Gemfile and bundle it up:

gem 'scratch'

These mixins are included in ActiveRecord with this gem, they could (theoretically) be used inside any other classes, but this hasn't been tested (nor documented) yet.

The normalize method help you create callbacks to normalize some attributes in a simple declarative manner.

Say you'd like to set all blank attributes to nil before validation, you could do:

normalize before: :validation, when: :blank?, set: nil

The before option default to :validation so it can be omitted in that case. You can also pass a block to normalize that will be given the value of the attribute and should return it's normalized form:

normalize { |value| value.strip }

The block in that example is a common pattern that can be replaced by the method option:

normalize method: :strip

There's two specialized mixins which are variant of the above examples...

The stripify method will strip all attributes, it also support all of normalize options. Here's an example using the except option:

stripify except: :foo

Don't like odd numbers, here's a solution:

nilify only: [:foo, :bar], when: :odd?, before: :save

Want to use join for user facing stuff but doesn't want to clean up the array yourself, use strip_join:

[1, 2, nil, '', '    ' , '   3  '].strip_join ', '
#=> "1, 2, 3"

Have many keys to look-up and need the first one available, use fetch_or:

h = { a: 1, b: 2, c: 3 }
h.fetch_or :e, :d, :c
#=> 3
# also support a `default` option...
h.fetch_or :x, :y, :z, default: nil
#=> nil
# when no default is given, act like `fetch` and raise a `KeyError`

You're stuck with a hash having arrays as values and need to invert it?

h = { west_coast: %w(WA OR CA AZ), east_east: %w(ME VT NY NJ) }
y = h.invert_splat
y['NJ']
#=> :east_coast

This project rocks and uses MIT-LICENSE!