Adds MethodWriter and MethodQuery extensions.

lib/hashie/extensions/method_access.rb

@@ -31,25 +31,88 @@ def respond_to?(name)
         return true if key?(name.to_s) || key?(name.to_sym)
         super
       end
+
       def method_missing(name, *args)
         return self[name.to_s] if key?(name.to_s)
         return self[name.to_sym] if key?(name.to_sym)
         super
       end
     end
 
+    # MethodWriter gives you #key_name= shortcuts for
+    # writing to your hash. Keys are written as strings,
+    # override #convert_key if you would like to have symbols
+    # or something else.
+    #
+    # Note that MethodWriter also overrides #respond_to such
+    # that any #method_name= will respond appropriately as true.
+    #
+    # @example
+    #   class MyHash < Hash
+    #     include Hashie::Extensions::MethodWriter
+    #   end
+    #
+    #   h = MyHash.new
+    #   h.awesome = 'sauce'
+    #   h['awesome'] # => 'sauce'
+    #
     module MethodWriter
+      def respond_to?(name)
+        return true if name.to_s =~ /=$/
+        super
+      end
+
       def method_missing(name, *args)
+        if args.size == 1 && name.to_s =~ /(.*)=$/
+          return self[convert_key($1)] = args.first
+        end
 
+        super
+      end
+
+      def convert_key(key)
+        key.to_s
       end
     end
 
+    # MethodQuery gives you the ability to check for the truthiness
+    # of a key via method calls. Note that it will return false if
+    # the key is set to a non-truthful value, not if the key isn't
+    # set at all. Use #key? for checking if a key has been set.
+    #
+    # MethodQuery will check against both string and symbol names
+    # of the method for existing keys. It also patches #respond_to
+    # to appropriately detect the query methods.
+    #
+    # @example
+    #   class MyHash < Hash
+    #     include Hashie::Extensions::MethodQuery
+    #   end
+    #
+    #   h = MyHash.new
+    #   h['abc'] = 123
+    #   h.abc? # => true
+    #   h['def'] = nil
+    #   h.def? # => false
+    #   h.hji? # => NoMethodError
     module MethodQuery
+      def respond_to?(name)
+        return true if name.to_s =~ /(.*)\?$/ && (key?($1) || key?($1.to_sym))
+        super
+      end
+
       def method_missing(name, *args)
+        if args.empty? && name.to_s =~ /(.*)\?$/ && (key?($1) || key?($1.to_sym))
+          return self[$1] || self[$1.to_sym]
+        end
 
+        super
       end
     end
 
+    # A macro module that will automatically include MethodReader,
+    # MethodWriter, and MethodQuery, giving you the ability to read,
+    # write, and query keys in a hash using method call shortcuts.
     module MethodAccess
       def self.included(base)
         [MethodReader, MethodWriter, MethodQuery].each do |mod|

spec/hashie/extensions/method_access_spec.rb

@@ -39,3 +39,74 @@ def initialize(hash = {}); self.update(hash) end
     end
   end
 end
+
+describe Hashie::Extensions::MethodWriter do
+  class WriterHash < Hash
+    include Hashie::Extensions::MethodWriter
+  end
+  subject{ WriterHash.new }
+
+  it 'should write from a method call' do
+    subject.awesome = 'sauce'
+    subject['awesome'].should == 'sauce'
+  end
+
+  it 'should convert the key using the #convert_key method' do
+    subject.stub!(:convert_key).and_return(:awesome)
+    subject.awesome = 'sauce'
+    subject[:awesome].should == 'sauce'
+  end
+
+  it 'should still NoMethodError on non equals-ending methods' do
+    lambda{ subject.awesome }.should raise_error(NoMethodError)
+  end
+
+  it 'should #respond_to? properly' do
+    subject.should be_respond_to(:abc=)
+    subject.should_not be_respond_to(:abc)
+  end
+end
+
+describe Hashie::Extensions::MethodQuery do
+  class QueryHash < Hash
+    def initialize(hash = {}); self.update(hash) end
+    include Hashie::Extensions::MethodQuery
+  end
+  subject{ QueryHash }
+
+  it 'should be true for non-nil string key values' do
+    subject.new('abc' => 123).should be_abc
+  end
+
+  it 'should be true for non-nil symbol key values' do
+    subject.new(:abc => 123).should be_abc
+  end
+
+  it 'should be false for nil key values' do
+    subject.new(:abc => false).should_not be_abc
+  end
+
+  it 'should raise a NoMethodError for non-set keys' do
+    lambda{ subject.new.abc? }.should raise_error(NoMethodError)
+  end
+
+  it 'should respond_to? for existing string keys' do
+    subject.new('abc' => 'def').should be_respond_to('abc?')
+  end
+
+  it 'should respond_to? for existing symbol keys' do
+    subject.new(:abc => 'def').should be_respond_to(:abc?)
+  end
+
+  it 'should not respond_to? for non-existent keys' do
+    subject.new.should_not be_respond_to('abc?')
+  end
+end
+
+describe Hashie::Extensions::MethodAccess do
+  it 'should include all of the other method mixins' do
+    klass = Class.new(Hash)
+    klass.send :include, Hashie::Extensions::MethodAccess
+    (klass.ancestors & [Hashie::Extensions::MethodReader, Hashie::Extensions::MethodWriter, Hashie::Extensions::MethodQuery]).size.should == 3
+  end
+end