lib/pairwise/pair_collection.rb
module Pairwise
class PairCollection < Array
def initialize(input_parameter_values, input_value_lists, input_parameter_index)
pairs = generate_pairs_between(input_parameter_values, input_value_lists, input_parameter_index)
@combination_history = []
super(pairs)
end
def remove_pairs_covered_by!(extended_input_list)
self.reject!{|pair| pair.covered_by?(extended_input_list)}
end
def input_combination_that_covers_most_pairs(input_combination, input_values_for_growth)
candidates = input_values_for_growth.map{|value| input_combination + [value]}
max_combination = candidates.max {|combination_1, combination_2| pairs_covered_count(combination_1) <=> pairs_covered_count(combination_2)}
possible_max_combinations = candidates.select{|combination| pairs_covered_count(max_combination) == pairs_covered_count(combination)}
winner = if possible_max_combinations.size > 1 && !@combination_history.empty?
find_most_different_combination(possible_max_combinations)
else
possible_max_combinations[0]
end
@combination_history << winner
winner
end
def to_a
self.map{|list| list.to_a}
end
private
def generate_pairs_between(input_parameter_values, input_value_lists, input_parameter_index)
pairs = []
input_parameter_values.each do |input_value_a|
input_value_lists.each_with_index do |input_list, input_value_b_index|
input_list.each do |input_value_b|
pairs << TestPair.new(input_parameter_index, input_value_b_index, input_value_a, input_value_b)
end
end
end
pairs
end
def pairs_covered_count(input_combination)
self.reduce(0) do |covered_count, pair|
covered_count += 1 if pair.covered_by?(input_combination)
covered_count
end
end
def find_most_different_combination(options)
scores = options.map do |option|
score(option)
end.flatten
_, winner_index = *scores.each_with_index.max
options[winner_index]
end
def score(option)
#O(n^2)
@combination_history.map do |previous_combination|
option.each_with_index.inject(0) do |difference_score, (value, index)|
value != previous_combination[index] ? difference_score : difference_score += 1
end
end.max
end
end
end