README.md

Flattening an array

Usage

git clone git@gist.github.com:99a322d2a4a2bcf4e7c157ee8aae1ddd.git flattening-an-array
cd flattening-an-array
bundle install
ruby tests.rb

License

MIT

Gemfile

source 'https://rubygems.org'

gem "minitest"

tests.rb

require "minitest/autorun"

# Public: Irons out an array.
#
# array - the array to be ironed out
#
# Examples
#   
#   iron([1, [2]])
#   # => [1, 2]
#
#   iron([1, [2, [3]]])
#   # => [1, 2, 3]
#
# Returns the ironed out Array.
def iron(array, flattened = [])
  array.each do |element|
    if element.is_a?(Array)
      iron(element, flattened)
    else
      flattened << element
    end
  end

  flattened
end

describe "#iron" do
  it "iron([]) => []" do
    iron([]).must_equal []
  end

  it "iron([1]) => [1]" do
    iron([1]).must_equal [1]
  end

  it "iron([1, 2, 3]) => [1, 2, 3]" do
    iron([1, 2, 3]).must_equal [1, 2, 3]
  end

  it "iron([[1]]) => [1]" do 
    iron([1]).must_equal [1]
  end

  it "iron([1, [2]]) => [1, 2]" do
    iron([1, [2]]).must_equal [1, 2]
  end

  it "iron([1, [2, [3]]]) => [1, 2, 3]" do
    iron([1, [2, [3]]]).must_equal [1, 2, 3]
  end

  it "iron([1, [2, [3, [4, [5, [6, [7]]]]]]]) => [1, 2, 3, 4, 5, 6, 7]" do
    iron([1, [2, [3, [4, [5, [6, [7]]]]]]]).must_equal [1, 2, 3, 4, 5, 6, 7]
  end
end