ActiveRecord like where for array of hashes in ruby

Edit : Updated the code as per the suggestions made by Masklinn.

Recently I was working on Issue#1 of my Soulmate Rails gem, which is a very simple and obvious optimization that I should have thought of myself. Thanks to lephyrius though for pointing it out. In my search method I was looping through the search results and calling find on each to get it from db. The fix involved to instead use a single where for all ids so that it translates to a single db call. A simple fix as well as an optimization.

However once I implemented it, I notice my tests were failing. On closer inspection I found they are failing because the models I created for testing using supermodel gem, didn’t have a where method. For a moment I thought WTF, and then I headed on to supermodel git repo and looked through the source and to my surprise, it in fact did not implement a where method. So I took it upon myself to do it.

Here’s the generic code I wrote that could be applied to any array of hashes :

def where(records, options) do |r|
    options.all? do |k, v|
      if v.is_a?(Enumerable)
        r[k] == v

Now you can do

# Eg.1)
where(records, :first_name => 'Dhruva', :last_name => 'Sagar')
# Eg.2)
where(records, :id => [1, 2, 3])

And you will get what you’d expect.

I updated supermodel in my fork to support such a where method and have sent the original author a pull request, hopefully it will get pulled soon.

All my tests pass now! Yay! I have released v0.3.0 of Soulname Rails. Be sure to check it out.

PS : How about a code review ? Is this optimal or can it be improved further ? I’d like to hear thoughts from others.

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