gistfile1.rb

# This creates a hash with an array of keys which only uses the first value, so the hash is probably unecessary.
# Is there a way to map the given `locations_by_display_name`, find a location name for each one, and return that value?

# The method seems to complex for what it needs to do, and am having difficulty simplifying it.

def actual_from_display_name(locations_by_display_name)
  actual_locations = []
  result = Hash.new { |h, k| h[k]=[] }.tap do |h|
    locations_with_display_name.each { |k, v| h[k] << v }
  end
  result.select { |_, v| locations_by_display_name.include?(v.first) }.each do |location|
    actual_locations << location.first
  end
  actual_locations
end

# This is an alternative I have tried (it works), but it's quiet loopy (I feel like I could use map within map?):
def actual_from_display_name(locations_by_display_name)
  actual_locations = []
  locations_with_display_name.each do |loc|
    locations_by_display_name.each do |name|
      if loc.include? name
        actual_locations << loc[0]
      end
    end
  end
  actual_locations
end

# Most recent iteration (nested maps):

def actual_from_display_name(locations_by_display_name)
  locations_with_display_name.map do |loc|
    locations_by_display_name.map do |name|
      loc[0] if loc.include? name
    end.compact
  end.flatten
end

#test
# locations_with_display_name returns something like:  [["unknown", "unknown"],["alphabet soup", "123123123124"]]
context '#actual_from_display_name' do
  it 'returns a list of actual locations when given humanized versions' do
    location_service = LocationService.new('potato')
    assert_equal ["unknown", "alphabet soup"],
      location_service.actual_from_display_name(["unknown", "123123123124"])
  end
end