diff options
Diffstat (limited to 'activesupport/lib/active_support/core_ext/object/deep_dup.rb')
-rw-r--r-- | activesupport/lib/active_support/core_ext/object/deep_dup.rb | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/activesupport/lib/active_support/core_ext/object/deep_dup.rb b/activesupport/lib/active_support/core_ext/object/deep_dup.rb new file mode 100644 index 0000000000..883f5f556c --- /dev/null +++ b/activesupport/lib/active_support/core_ext/object/deep_dup.rb @@ -0,0 +1,44 @@ +class Object + # Returns a deep copy of object if it's duplicable. If it's + # not duplicable, returns +self+. + # + # object = Object.new + # dup = object.deep_dup + # dup.instance_variable_set(:@a, 1) + # + # object.instance_variable_defined?(:@a) #=> false + # dup.instance_variable_defined?(:@a) #=> true + def deep_dup + duplicable? ? dup : self + end +end + +class Array + # Returns a deep copy of array. + # + # array = [1, [2, 3]] + # dup = array.deep_dup + # dup[1][2] = 4 + # + # array[1][2] #=> nil + # dup[1][2] #=> 4 + def deep_dup + map { |it| it.deep_dup } + end +end + +class Hash + # Returns a deep copy of hash. + # + # hash = { a: { b: 'b' } } + # dup = hash.deep_dup + # dup[:a][:c] = 'c' + # + # hash[:a][:c] #=> nil + # dup[:a][:c] #=> "c" + def deep_dup + each_with_object(dup) do |(key, value), hash| + hash[key.deep_dup] = value.deep_dup + end + end +end |