mirror of
https://github.com/mruby/mruby
synced 2026-06-08 16:11:16 +00:00
Yukihiro "Matz" Matsumoto
f3cd991771
add tap_each method that yields each element for side effects (e.g. logging, debugging) and passes it through unmodified. see https://bugs.ruby-lang.org/issues/21520 Co-authored-by: Claude <noreply@anthropic.com>
85 lines
2.1 KiB
Ruby
85 lines
2.1 KiB
Ruby
assert("Enumerator::Lazy") do
|
|
a = [1, 2]
|
|
assert_equal Enumerator::Lazy, a.lazy.class
|
|
end
|
|
|
|
assert("Enumerator::Lazy laziness") do
|
|
a = Object.new
|
|
def a.each
|
|
return to_enum :each unless block_given?
|
|
self.b << 10
|
|
yield 1
|
|
self.b << 20
|
|
yield 2
|
|
self.b << 30
|
|
yield 3
|
|
self.b << 40
|
|
yield 4
|
|
self.b << 50
|
|
yield 5
|
|
end
|
|
def a.b(b=nil)
|
|
@b = b if b
|
|
@b
|
|
end
|
|
|
|
a.b([])
|
|
assert_equal [1,2], a.each.lazy.take(2).force
|
|
assert_equal [10,20], a.b
|
|
|
|
a.b([])
|
|
assert_equal [2,4], a.each.lazy.select{|x|x%2==0}.take(2).force
|
|
assert_equal [10,20,30,40], a.b
|
|
|
|
a.b([])
|
|
assert_equal [1], a.each.lazy.take_while{|x|x<2}.take(1).force
|
|
assert_equal [10], a.b
|
|
|
|
a.b([])
|
|
assert_equal [1], a.each.lazy.take_while{|x|x<2}.take(4).force
|
|
assert_equal [10,20], a.b
|
|
end
|
|
|
|
assert("Enumerator::Lazy#to_enum") do
|
|
lazy_enum = (0..).lazy.to_enum(:each_slice, 2)
|
|
assert_kind_of Enumerator::Lazy, lazy_enum
|
|
assert_equal [0*1, 2*3, 4*5, 6*7], lazy_enum.map { |a| a.first * a.last }.first(4)
|
|
end
|
|
|
|
assert("Enumerator::Lazy#flat_map with array from block") do
|
|
assert_equal [1, 10, 2, 20, 3, 30], [1, 2, 3].lazy.flat_map {|x| [x, x*10]}.force
|
|
end
|
|
|
|
assert("Enumerator::Lazy#flat_map with non-enumerable from block") do
|
|
assert_equal [1, 2, 3], [1, 2, 3].lazy.flat_map {|x| x}.force
|
|
end
|
|
|
|
assert("Enumerator::Lazy#flat_map with nested array from block") do
|
|
assert_equal [[1, 2], [3, 4]], [1, 3].lazy.flat_map {|x| [[x, x+1]]}.force
|
|
end
|
|
|
|
assert("Enumerator::Lazy#grep_v") do
|
|
lazy_grep_v = (0..).lazy.grep_v(2..4)
|
|
assert_kind_of Enumerator::Lazy, lazy_grep_v
|
|
assert_equal [0, 1, 5, 6], lazy_grep_v.first(4)
|
|
end
|
|
|
|
assert("Enumerator::Lazy#tap_each") do
|
|
seen = []
|
|
result = [1, 2, 3, 4, 5].lazy.tap_each{|x| seen << x }.select{|x| x % 2 == 0 }.force
|
|
assert_equal [2, 4], result
|
|
assert_equal [1, 2, 3, 4, 5], seen
|
|
end
|
|
|
|
assert("Enumerator::Lazy#tap_each laziness") do
|
|
seen = []
|
|
[1, 2, 3, 4, 5].lazy.tap_each{|x| seen << x }.first(3)
|
|
assert_equal [1, 2, 3], seen
|
|
end
|
|
|
|
assert("Enumerator::Lazy#zip with cycle") do
|
|
e1 = [1, 2, 3].cycle
|
|
e2 = [:a, :b].cycle
|
|
assert_equal [[1,:a],[2,:b],[3,:a]], e1.lazy.zip(e2).first(3)
|
|
end
|