diff options
Diffstat (limited to 'spec/ruby/core/array/each_spec.rb')
-rw-r--r-- | spec/ruby/core/array/each_spec.rb | 40 |
1 files changed, 37 insertions, 3 deletions
diff --git a/spec/ruby/core/array/each_spec.rb b/spec/ruby/core/array/each_spec.rb index 256647d61e..57d6082f01 100644 --- a/spec/ruby/core/array/each_spec.rb +++ b/spec/ruby/core/array/each_spec.rb @@ -1,11 +1,13 @@ require_relative '../../spec_helper' require_relative 'fixtures/classes' require_relative 'shared/enumeratorize' +require_relative 'shared/iterable_and_tolerating_size_increasing' require_relative '../enumerable/shared/enumeratorized' -# Modifying a collection while the contents are being iterated -# gives undefined behavior. See -# http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/23633 +# Mutating the array while it is being iterated is discouraged as it can result in confusing behavior. +# Yet a Ruby implementation must not crash in such a case, and following the simple CRuby behavior makes sense. +# CRuby simply reads the array storage and checks the size for every iteration; +# like `i = 0; while i < size; yield self[i]; end` describe "Array#each" do it "yields each element to the block" do @@ -15,6 +17,34 @@ describe "Array#each" do a.should == [1, 2, 3] end + it "yields each element to the block even if the array is changed during iteration" do + a = [1, 2, 3, 4, 5] + iterated = [] + a.each { |x| iterated << x; a << x+5 if x.even? } + iterated.should == [1, 2, 3, 4, 5, 7, 9] + end + + it "yields only elements that are still in the array" do + a = [0, 1, 2, 3, 4] + iterated = [] + a.each { |x| iterated << x; a.pop if x.even? } + iterated.should == [0, 1, 2] + end + + it "yields elements based on an internal index" do + a = [0, 1, 2, 3, 4] + iterated = [] + a.each { |x| iterated << x; a.shift if x.even? } + iterated.should == [0, 2, 4] + end + + it "yields the same element multiple times if inserting while iterating" do + a = [1, 2] + iterated = [] + a.each { |x| iterated << x; a.unshift(0) if a.size == 2 } + iterated.should == [1, 1, 2] + end + it "yields each element to a block that takes multiple arguments" do a = [[1, 2], :a, [3, 4]] b = [] @@ -46,3 +76,7 @@ describe "Array#each" do it_behaves_like :enumeratorize, :each it_behaves_like :enumeratorized_with_origin_size, :each, [1,2,3] end + +describe "Array#each" do + it_behaves_like :array_iterable_and_tolerating_size_increasing, :each +end |