angelikatyborska's solution to Word Count on the Ruby track

Instructions

Test suite

Solution

Note:

This solution was written on an old version of Exercism. The tests below might not correspond to the solution code, and the exercise may have changed since this code was written.

Given a phrase, count the occurrences of each word in that phrase.

For example for the input "olly olly in come free"

olly: 2
in: 1
come: 1
free: 1

For installation and learning resources, refer to the exercism help page.

For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest:

gem install minitest

If you would like color output, you can require 'minitest/pride' in the test file, or note the alternative instruction, below, for running the test file.

Run the tests from the exercise directory using the following command:

ruby word_count_test.rb

To include color from the command line:

ruby -r minitest/pride word_count_test.rb

Source

This is a classic toy problem, but we were reminded of it by seeing it in the Go Tour.

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

word_count_test.rb

require 'minitest/autorun'
require_relative 'word_count'

# Common test data version: 1.0.0 cd26d49
class WordCountTest < Minitest::Test
  def test_count_one_word
    # skip
    phrase = Phrase.new("word")
    counts = {"word"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_count_one_of_each_word
    skip
    phrase = Phrase.new("one of each")
    counts = {"one"=>1, "of"=>1, "each"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_multiple_occurrences_of_a_word
    skip
    phrase = Phrase.new("one fish two fish red fish blue fish")
    counts = {"one"=>1, "fish"=>4, "two"=>1, "red"=>1, "blue"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_handles_cramped_lists
    skip
    phrase = Phrase.new("one,two,three")
    counts = {"one"=>1, "two"=>1, "three"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_handles_expanded_lists
    skip
    phrase = Phrase.new("one,\ntwo,\nthree")
    counts = {"one"=>1, "two"=>1, "three"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_ignore_punctuation
    skip
    phrase = Phrase.new("car: carpet as java: javascript!!&@$%^&")
    counts = {"car"=>1, "carpet"=>1, "as"=>1, "java"=>1, "javascript"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_include_numbers
    skip
    phrase = Phrase.new("testing, 1, 2 testing")
    counts = {"testing"=>2, "1"=>1, "2"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_normalize_case
    skip
    phrase = Phrase.new("go Go GO Stop stop")
    counts = {"go"=>3, "stop"=>2}
    assert_equal counts, phrase.word_count
  end

  def test_with_apostrophes
    skip
    phrase = Phrase.new("First: don't laugh. Then: don't cry.")
    counts = {"first"=>1, "don't"=>2, "laugh"=>1, "then"=>1, "cry"=>1}
    assert_equal counts, phrase.word_count
  end

  def test_with_quotations
    skip
    phrase = Phrase.new("Joe can't tell between 'large' and large.")
    counts = {"joe"=>1, "can't"=>1, "tell"=>1, "between"=>1, "large"=>2, "and"=>1}
    assert_equal counts, phrase.word_count
  end

  # Problems in exercism evolve over time, as we find better ways to ask
  # questions.
  # The version number refers to the version of the problem you solved,
  # not your solution.
  #
  # Define a constant named VERSION inside of the top level BookKeeping
  # module, which may be placed near the end of your file.
  #
  # In your file, it will look like this:
  #
  # module BookKeeping
  #   VERSION = 1 # Where the version number matches the one in the test.
  # end
  #
  # If you are curious, read more about constants on RubyDoc:
  # http://ruby-doc.org/docs/ruby-doc-bundle/UsersGuide/rg/constants.html

  def test_bookkeeping
    skip
    assert_equal 1, BookKeeping::VERSION
  end
end

class Phrase
  VERSION = 1

  def initialize(phrase)
    @phrase = phrase
  end

  def word_count
    counts = {}

    normalized_phrase = remove_punctuation(@phrase).downcase

    normalized_phrase.split.each do |word|
      counts[word] ||= 0
      counts[word] += 1
    end

    counts
  end

  private

  def remove_punctuation(phrase)
    # apostrophes permitted only for abbreviations
    phrase_without_apostrophes = remove_apostrophes_except_between_word_chars(phrase)
    remove_punctuation_except_apostrophes(phrase_without_apostrophes)
  end

  def remove_apostrophes_except_between_word_chars(phrase)
    phrase.gsub(/(?<=\W)'|'(?=\W)/, '')
  end

  def remove_punctuation_except_apostrophes(phrase)
    phrase.gsub(/[^\w']/, ' ')
  end
end

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angelikatyborska's solution

to Word Count in the Ruby Track