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##
# Enumerable(Ext) Test
assert("Enumerable#drop") do
a = [1, 2, 3, 4, 5, 0]
assert_equal [4, 5, 0], a.drop(3)
assert_equal [], a.drop(6)
end
assert("Enumerable#drop_while") do
a = [1, 2, 3, 4, 5, 0]
assert_equal [3, 4, 5, 0], a.drop_while {|i| i < 3 }
end
assert("Enumerable#take") do
a = [1, 2, 3, 4, 5, 0]
assert_equal [1, 2, 3], a.take(3)
end
assert("Enumerable#take_while") do
a = [1, 2, 3, 4, 5, 0]
assert_equal [1, 2], a.take_while {|i| i < 3}
end
assert("Enumerable#each_cons") do
a = []
(1..5).each_cons(3){|e| a << e}
assert_equal [[1, 2, 3], [2, 3, 4], [3, 4, 5]], a
end
assert("Enumerable#each_slice") do
a = []
(1..10).each_slice(3){|e| a << e}
assert_equal [[1, 2, 3], [4, 5, 6], [7, 8, 9], [10]], a
end
assert("Enumerable#group_by") do
r = (1..6).group_by {|i| i % 3 }
assert_equal [3, 6], r[0]
assert_equal [1, 4], r[1]
assert_equal [2, 5], r[2]
end
assert("Enumerable#sort_by") do
assert_equal ["car", "train", "bicycle"], %w{car bicycle train}.sort_by {|e| e.length}
end
assert("Enumerable#first") do
a = Object.new
a.extend Enumerable
def a.each
yield 1
yield 2
yield 3
end
assert_equal 1, a.first
assert_equal [1, 2], a.first(2)
assert_equal [1, 2, 3], a.first(10)
a = Object.new
a.extend Enumerable
def a.each
end
assert_nil a.first
end
assert("Enumerable#count") do
a = [1, 2, 4, 2]
assert_equal 4, a.count
assert_equal 2, a.count(2)
assert_equal 3, a.count{|x| x % 2 == 0}
end
assert("Enumerable#flat_map") do
assert_equal [1, 2, 3, 4], [1, 2, 3, 4].flat_map { |e| e }
assert_equal [1, -1, 2, -2, 3, -3, 4, -4], [1, 2, 3, 4].flat_map { |e| [e, -e] }
assert_equal [1, 2, 100, 3, 4, 100], [[1, 2], [3, 4]].flat_map { |e| e + [100] }
end
assert("Enumerable#max_by") do
assert_equal "albatross", %w[albatross dog horse].max_by { |x| x.length }
end
assert("Enumerable#min_by") do
assert_equal "dog", %w[albatross dog horse].min_by { |x| x.length }
end
assert("Enumerable#minmax") do
a = %w(albatross dog horse)
assert_equal ["albatross", "horse"], a.minmax
assert_equal ["dog", "albatross"], a.minmax { |a, b| a.length <=> b.length }
end
assert("Enumerable#minmax_by") do
assert_equal ["dog", "albatross"], %w(albatross dog horse).minmax_by { |x| x.length }
end
assert("Enumerable#none?") do
assert_true %w(ant bear cat).none? { |word| word.length == 5 }
assert_false %w(ant bear cat).none? { |word| word.length >= 4 }
assert_true [].none?
assert_true [nil, false].none?
assert_false [nil, true].none?
end
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