diff options
-rw-r--r-- | CHANGELOG.md | 1 | ||||
-rw-r--r-- | lib/hashie/extensions/deep_merge.rb | 17 | ||||
-rw-r--r-- | lib/hashie/utils.rb | 28 | ||||
-rw-r--r-- | spec/hashie/extensions/deep_merge_spec.rb | 53 |
4 files changed, 93 insertions, 6 deletions
diff --git a/CHANGELOG.md b/CHANGELOG.md index 259fa31..23892eb 100644 --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -28,6 +28,7 @@ scheme are considered to be bugs. ### Fixed +* [#467](https://github.com/intridea/hashie/pull/467): Fixed `DeepMerge#deep_merge` mutating nested values within the receiver - [@michaelherold](https://github.com/michaelherold). * Your contribution here. ### Security diff --git a/lib/hashie/extensions/deep_merge.rb b/lib/hashie/extensions/deep_merge.rb index 5363904..1890e8f 100644 --- a/lib/hashie/extensions/deep_merge.rb +++ b/lib/hashie/extensions/deep_merge.rb @@ -3,7 +3,7 @@ module Hashie module DeepMerge # Returns a new hash with +self+ and +other_hash+ merged recursively. def deep_merge(other_hash, &block) - copy = dup + copy = _deep_dup(self) copy.extend(Hashie::Extensions::DeepMerge) unless copy.respond_to?(:deep_merge!) copy.deep_merge!(other_hash, &block) end @@ -18,6 +18,21 @@ module Hashie private + def _deep_dup(hash) + copy = hash.dup + + copy.each do |key, value| + copy[key] = + if value.is_a?(::Hash) + _deep_dup(value) + else + Hashie::Utils.safe_dup(value) + end + end + + copy + end + def _recursive_merge(hash, other_hash, &block) other_hash.each do |k, v| hash[k] = diff --git a/lib/hashie/utils.rb b/lib/hashie/utils.rb index d8e05fe..5b55b9a 100644 --- a/lib/hashie/utils.rb +++ b/lib/hashie/utils.rb @@ -12,5 +12,33 @@ module Hashie "defined in #{bound_method.owner}" end end + + # Duplicates a value or returns the value when it is not duplicable + # + # @api public + # + # @param value [Object] the value to safely duplicate + # @return [Object] the duplicated value + def self.safe_dup(value) + case value + when Complex, FalseClass, NilClass, Rational, Method, Symbol, TrueClass, *integer_classes + value + else + value.dup + end + end + + # Lists the classes Ruby uses for integers + # + # @api private + # @return [Array<Class>] + def self.integer_classes + @integer_classes ||= + if const_defined?(:Fixnum) + [Fixnum, Bignum] # rubocop:disable Lint/UnifiedInteger + else + [Integer] + end + end end end diff --git a/spec/hashie/extensions/deep_merge_spec.rb b/spec/hashie/extensions/deep_merge_spec.rb index ab79ff6..4ff6c30 100644 --- a/spec/hashie/extensions/deep_merge_spec.rb +++ b/spec/hashie/extensions/deep_merge_spec.rb @@ -14,19 +14,62 @@ describe Hashie::Extensions::DeepMerge do context 'without &block' do let(:h1) do - subject.new.merge(a: 'a', a1: 42, b: 'b', c: { c1: 'c1', c2: { a: 'b' }, c3: { d1: 'd1' } }) + subject.new.merge( + a: 'a', + a1: 42, + b: 'b', + c: { c1: 'c1', c2: { a: 'b' }, c3: { d1: 'd1' } }, + d: nil, + d1: false, + d2: true, + d3: unbound_method, + d4: Complex(1), + d5: Rational(1) + ) end let(:h2) { { a: 1, a1: 1, c: { c1: 2, c2: 'c2', c3: { d2: 'd2' } }, e: { e1: 1 } } } + let(:unbound_method) { method(:puts) } let(:expected_hash) do - { a: 1, a1: 1, b: 'b', c: { c1: 2, c2: 'c2', c3: { d1: 'd1', d2: 'd2' } }, e: { e1: 1 } } + { + a: 1, + a1: 1, + b: 'b', + c: { c1: 2, c2: 'c2', c3: { d1: 'd1', d2: 'd2' } }, + d: nil, + d1: false, + d2: true, + d3: unbound_method, + d4: Complex(1), + d5: Rational(1), + e: { e1: 1 } + } end - it 'deep merges two hashes' do - expect(h1.deep_merge(h2)).to eq expected_hash + it 'deep merges two hashes without modifying them' do + result = h1.deep_merge(h2) + + expect(result).to eq expected_hash + expect(h1).to( + eq( + a: 'a', + a1: 42, + b: 'b', + c: { c1: 'c1', c2: { a: 'b' }, c3: { d1: 'd1' } }, + d: nil, + d1: false, + d2: true, + d3: unbound_method, + d4: Complex(1), + d5: Rational(1) + ) + ) + expect(h2).to eq(a: 1, a1: 1, c: { c1: 2, c2: 'c2', c3: { d2: 'd2' } }, e: { e1: 1 }) end it 'deep merges another hash in place via bang method' do - h1.deep_merge!(h2) + result = h1.deep_merge!(h2) + + expect(result).to eq expected_hash expect(h1).to eq expected_hash end |