Add failing spec + fix it

fixed

update changelog

3 files changed, 26 insertions, 5 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index af196fa..b6d0458 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,7 @@
 * [#179](https://github.com/intridea/hashie/pull/179): Mash#values_at will convert each key before doing the lookup - [@nahiluhmot](https://github.com/nahiluhmot).
 * [#184](https://github.com/intridea/hashie/pull/184): Allow ranges on Rash to match all Numeric types - [@medcat](https://github.com/medcat).
 * [#187](https://github.com/intridea/hashie/pull/187): Automatically require version - [@medcat](https://github.com/medcat).
+* [#190](https://github.com/intridea/hashie/issues/190): Fixed `coerce_key` with `from` Trash feature and Coercion extension - [@gregory](https://github.com/gregory).
 * Your contribution here.
 
 ## 3.1 (6/25/2014)
diff --git a/lib/hashie/extensions/coercion.rb b/lib/hashie/extensions/coercion.rb
index 4486ae9..dea6e92 100644
--- a/lib/hashie/extensions/coercion.rb
+++ b/lib/hashie/extensions/coercion.rb
@@ -2,16 +2,19 @@ module Hashie
   module Extensions
     module Coercion
       def self.included(base)
-        base.extend ClassMethods
         base.send :include, InstanceMethods
+        base.extend ClassMethods # NOTE: we wanna make sure we first define set_value_with_coercion before extending
+
+        base.send :alias_method, :'set_value_without_coercion', :[]=
+        base.send :alias_method, :[]=, :'set_value_with_coercion'
       end
 
       module InstanceMethods
-        def []=(key, value)
+        def set_value_with_coercion(key, value)
           into = self.class.key_coercion(key) || self.class.value_coercion(value)
 
-          return super(key, value) unless value && into
-          return super(key, coerce_or_init(into).call(value)) unless into.is_a?(Enumerable)
+          return set_value_without_coercion(key, value) unless value && into
+          return set_value_without_coercion(key, coerce_or_init(into).call(value)) unless into.is_a?(Enumerable)
 
           if into.class >= Hash
             key_coerce = coerce_or_init(into.flatten[0])
@@ -22,7 +25,7 @@ module Hashie
             value = into.class.new(value.map { |v| value_coerce.call(v) })
           end
 
-          super(key, value)
+          set_value_without_coercion(key, value)
         end
 
         def coerce_or_init(type)
diff --git a/spec/hashie/extensions/coercion_spec.rb b/spec/hashie/extensions/coercion_spec.rb
index d73e884..40cc8e1 100644
--- a/spec/hashie/extensions/coercion_spec.rb
+++ b/spec/hashie/extensions/coercion_spec.rb
@@ -156,6 +156,23 @@ describe Hashie::Extensions::Coercion do
         expect(tweet[:user]).to be_a(UserMash)
       end
     end
+
+    context 'when used with a Trash' do
+      class UserTrash < Hashie::Trash
+        property :email
+      end
+      class TweetTrash < Hashie::Trash
+        include Hashie::Extensions::Coercion
+
+        property :user, from: :user_data
+        coerce_key :user, UserTrash
+      end
+
+      it 'coerces with instance initialization' do
+        tweet = TweetTrash.new(user_data: { email: 'foo@bar.com' })
+        expect(tweet[:user]).to be_a(UserTrash)
+      end
+    end
   end
 
   describe '#coerce_value' do