Merge pull request #304 from regexident/master

Fixed #303 (deep_merge/stringify_keys/symbolize_keys not working via hash.extend(…))

7 files changed, 85 insertions, 10 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a5740cf..81d2289 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,7 @@
 ## Next Release
 
 * Your contribution here.
+* [#304](https://github.com/intridea/hashie/pull/304): Ensured compatibility of `Hash` extensions with singleton objects - [@regexident](https://github.com/regexident).
 
 ## 3.4.2 (6/2/2015)
 
diff --git a/lib/hashie/extensions/deep_merge.rb b/lib/hashie/extensions/deep_merge.rb
index d7222a3..df0887d 100644
--- a/lib/hashie/extensions/deep_merge.rb
+++ b/lib/hashie/extensions/deep_merge.rb
@@ -3,7 +3,9 @@ module Hashie
     module DeepMerge
       # Returns a new hash with +self+ and +other_hash+ merged recursively.
       def deep_merge(other_hash, &block)
-        dup.deep_merge!(other_hash, &block)
+        copy = dup
+        copy.extend(Hashie::Extensions::DeepMerge) unless copy.respond_to?(:deep_merge!)
+        copy.deep_merge!(other_hash, &block)
       end
 
       # Returns a new hash with +self+ and +other_hash+ merged recursively.
diff --git a/lib/hashie/extensions/stringify_keys.rb b/lib/hashie/extensions/stringify_keys.rb
index 13d50bc..41b0fe3 100644
--- a/lib/hashie/extensions/stringify_keys.rb
+++ b/lib/hashie/extensions/stringify_keys.rb
@@ -15,7 +15,7 @@ module Hashie
       # Return a new hash with all keys converted
       # to strings.
       def stringify_keys
-        dup.stringify_keys!
+        StringifyKeys.stringify_keys(self)
       end
 
       module ClassMethods
@@ -25,7 +25,7 @@ module Hashie
         def stringify_keys_recursively!(object)
           case object
           when self.class
-            object.stringify_keys!
+            stringify_keys!(object)
           when ::Array
             object.each do |i|
               stringify_keys_recursively!(i)
@@ -43,6 +43,7 @@ module Hashie
         #   test.stringify_keys!
         #   test # => {'abc' => 'def'}
         def stringify_keys!(hash)
+          hash.extend(Hashie::Extensions::StringifyKeys) unless hash.respond_to?(:stringify_keys!)
           hash.keys.each do |k|
             stringify_keys_recursively!(hash[k])
             hash[k.to_s] = hash.delete(k)
@@ -54,8 +55,10 @@ module Hashie
         # to strings.
         # @param [::Hash] hash
         def stringify_keys(hash)
-          hash.dup.tap do | new_hash |
-            stringify_keys! new_hash
+          copy = hash.dup
+          copy.extend(Hashie::Extensions::StringifyKeys) unless copy.respond_to?(:stringify_keys!)
+          copy.tap do |new_hash|
+            stringify_keys!(new_hash)
           end
         end
       end
diff --git a/lib/hashie/extensions/symbolize_keys.rb b/lib/hashie/extensions/symbolize_keys.rb
index 12d0669..274889c 100644
--- a/lib/hashie/extensions/symbolize_keys.rb
+++ b/lib/hashie/extensions/symbolize_keys.rb
@@ -15,7 +15,7 @@ module Hashie
       # Return a new hash with all keys converted
       # to symbols.
       def symbolize_keys
-        dup.symbolize_keys!
+        SymbolizeKeys.symbolize_keys(self)
       end
 
       module ClassMethods
@@ -23,9 +23,9 @@ module Hashie
         # hashes and arrays.
         # @api private
         def symbolize_keys_recursively!(object)
-          object.symbolize_keys! if object.respond_to? :symbolize_keys!
-
           case object
+          when self.class
+            symbolize_keys!(object)
           when ::Array
             object.each do |i|
               symbolize_keys_recursively!(i)
@@ -43,6 +43,7 @@ module Hashie
         #   Hashie.symbolize_keys! test
         #   test # => {:abc => 'def'}
         def symbolize_keys!(hash)
+          hash.extend(Hashie::Extensions::SymbolizeKeys) unless hash.respond_to?(:symbolize_keys!)
           hash.keys.each do |k|
             symbolize_keys_recursively!(hash[k])
             hash[k.to_sym] = hash.delete(k)
@@ -54,8 +55,10 @@ module Hashie
         # to symbols.
         # @param [::Hash] hash
         def symbolize_keys(hash)
-          hash.dup.tap do | new_hash |
-            symbolize_keys! new_hash
+          copy = hash.dup
+          copy.extend(Hashie::Extensions::SymbolizeKeys) unless copy.respond_to?(:symbolize_keys!)
+          copy.tap do |new_hash|
+            symbolize_keys!(new_hash)
           end
         end
       end
diff --git a/spec/hashie/extensions/deep_merge_spec.rb b/spec/hashie/extensions/deep_merge_spec.rb
index cd68523..0815c15 100644
--- a/spec/hashie/extensions/deep_merge_spec.rb
+++ b/spec/hashie/extensions/deep_merge_spec.rb
@@ -42,4 +42,24 @@ describe Hashie::Extensions::DeepMerge do
       expect(h1).to eq expected_hash
     end
   end
+
+  context 'from extended object' do
+    subject { Hash }
+    let(:h1) { subject.new.merge(a: 100, c: { c1: 100 }).extend(Hashie::Extensions::DeepMerge) }
+    let(:h2) { { b: 250, c: { c1: 200 } } }
+    let(:expected_hash) { { a: 100, b: 250, c: { c1: 200 } } }
+
+    it 'does not raise error' do
+      expect { h1.deep_merge(h2) } .not_to raise_error
+    end
+
+    it 'deep merges two hashes' do
+      expect(h1.deep_merge(h2)).to eq expected_hash
+    end
+
+    it 'deep merges another hash in place via bang method' do
+      h1.deep_merge!(h2)
+      expect(h1).to eq expected_hash
+    end
+  end
 end
diff --git a/spec/hashie/extensions/stringify_keys_spec.rb b/spec/hashie/extensions/stringify_keys_spec.rb
index b0f8aa6..f5f78d8 100644
--- a/spec/hashie/extensions/stringify_keys_spec.rb
+++ b/spec/hashie/extensions/stringify_keys_spec.rb
@@ -80,6 +80,29 @@ describe Hashie::Extensions::StringifyKeys do
       include_examples 'stringify_keys!'
     end
   end
+
+  context 'singleton methods' do
+    subject { Hash }
+    let(:object) { subject.new.merge(a: 1, b: { c: 2 }).extend(Hashie::Extensions::StringifyKeys) }
+    let(:expected_hash) { { 'a' => 1, 'b' => { 'c' => 2 } } }
+
+    describe '.stringify_keys' do
+      it 'does not raise error' do
+        expect { object.stringify_keys } .not_to raise_error
+      end
+      it 'produces expected stringified hash' do
+        expect(object.stringify_keys).to eq(expected_hash)
+      end
+    end
+    describe '.stringify_keys!' do
+      it 'does not raise error' do
+        expect { object.stringify_keys! } .not_to raise_error
+      end
+      it 'produces expected stringified hash' do
+        expect(object.stringify_keys!).to eq(expected_hash)
+      end
+    end
+  end
 end
 
 describe Hashie do
diff --git a/spec/hashie/extensions/symbolize_keys_spec.rb b/spec/hashie/extensions/symbolize_keys_spec.rb
index 862117b..b62fbe4 100644
--- a/spec/hashie/extensions/symbolize_keys_spec.rb
+++ b/spec/hashie/extensions/symbolize_keys_spec.rb
@@ -85,6 +85,29 @@ describe Hashie::Extensions::SymbolizeKeys do
       include_examples 'symbolize_keys!'
     end
   end
+
+  context 'singleton methods' do
+    subject { Hash }
+    let(:object) { subject.new.merge('a' => 1, 'b' => { 'c' => 2 }).extend(Hashie::Extensions::SymbolizeKeys) }
+    let(:expected_hash) { { a: 1, b: { c: 2 } } }
+
+    describe '.symbolize_keys' do
+      it 'does not raise error' do
+        expect { object.symbolize_keys }.not_to raise_error
+      end
+      it 'produces expected symbolized hash' do
+        expect(object.symbolize_keys).to eq(expected_hash)
+      end
+    end
+    describe '.symbolize_keys!' do
+      it 'does not raise error' do
+        expect { object.symbolize_keys! }.not_to raise_error
+      end
+      it 'produces expected symbolized hash' do
+        expect(object.symbolize_keys!).to eq(expected_hash)
+      end
+    end
+  end
 end
 
 describe Hashie do