A simple Ruby code kata designed for rspec, inspired by Alex Chaffee's Test First Ruby.
Create a method, Array#each_count, which returns a count of discrete elements contained in the form of {element => count}.
Your method should meet the following criteria:
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When called without arguments or a block, it should iterate over each element of self, returning a count of its unique elements.
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It should accept a method (in symbol or string format) followed by any number of arguments as parameters. It should apply these parameters to each element of self, returning a count of each unique return value.
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It should accept a block, call the block on each element of self, and return a count of each unique return value.
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It should raise an exception if both arguments and a block are provided.
Given an array cities:
cities = ["Melbourne", "Dallas", "Taipei", "Toronto", "Dallas", "Kathmandu"]cities.each_count should return:
# => {"Melbourne"=>1, "Dallas"=>2, "Taipei"=>1, "Toronto"=>1, "Kathmandu"=>1}cities.each_count :length should return:
# => {9=>2, 6=>3, 7=>1}cities.each_count :gsub, /[aeiou]/, 'x' should return:
# => {"Mxlbxxrnx"=>1, "Dxllxs"=>2, "Txxpxx"=>1, "Txrxntx"=>1, "Kxthmxndx"=>1}cities.each_count {|city| city.length % 3 == 0} should return:
# => {true=>5, false=>1}Examples are provided as test cases in the /spec directory. Your goal is to factor your solution to get all of the tests to pass.