Added :instance_writer option to #mattr_writer/accessor, #cattr_writer/accessor, and #class_inheritable_writer to skip the creation of the instance writer. [Rick]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6050 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

8 files changed, 154 insertions, 2 deletions

diff --git a/activesupport/CHANGELOG b/activesupport/CHANGELOG
index 265dd53297..5c0e062403 100644
--- a/activesupport/CHANGELOG
+++ b/activesupport/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Added :instance_writer option to #mattr_writer/accessor, #cattr_writer/accessor, and #class_inheritable_writer to skip the creation of the instance writer.  [Rick]
+
 * Added Hash#to_query to turn a hash of values into a form-encoded query string [Nicholas Seckar]
 
 * Increase test coverage for subclasses_of. Closes #7335. [Roman2K, Nicholas Seckar]
diff --git a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
index 93a7d48f69..79247e00cb 100644
--- a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb
@@ -3,6 +3,7 @@
 class Class # :nodoc:
   def cattr_reader(*syms)
     syms.flatten.each do |sym|
+      next if sym.is_a?(Hash)
       class_eval(<<-EOS, __FILE__, __LINE__)
         unless defined? @@#{sym}
           @@#{sym} = nil
@@ -20,6 +21,7 @@ class Class # :nodoc:
   end
 
   def cattr_writer(*syms)
+    options = syms.last.is_a?(Hash) ? syms.pop : {}
     syms.flatten.each do |sym|
       class_eval(<<-EOS, __FILE__, __LINE__)
         unless defined? @@#{sym}
@@ -30,9 +32,11 @@ class Class # :nodoc:
           @@#{sym} = obj
         end
 
+        #{"
         def #{sym}=(obj)
           @@#{sym} = obj
         end
+        " unless options[:instance_writer] == false }
       EOS
     end
   end
diff --git a/activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb b/activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb
index bc8bf09ab2..3c5b2b8340 100644
--- a/activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb
+++ b/activesupport/lib/active_support/core_ext/class/inheritable_attributes.rb
@@ -9,6 +9,7 @@ end
 class Class # :nodoc:
   def class_inheritable_reader(*syms)
     syms.each do |sym|
+      next if sym.is_a?(Hash)
       class_eval <<-EOS
         def self.#{sym}
           read_inheritable_attribute(:#{sym})
@@ -22,43 +23,52 @@ class Class # :nodoc:
   end
 
   def class_inheritable_writer(*syms)
+    options = syms.last.is_a?(Hash) ? syms.pop : {}
     syms.each do |sym|
       class_eval <<-EOS
         def self.#{sym}=(obj)
           write_inheritable_attribute(:#{sym}, obj)
         end
 
+        #{"
         def #{sym}=(obj)
           self.class.#{sym} = obj
         end
+        " unless options[:instance_writer] == false }
       EOS
     end
   end
 
   def class_inheritable_array_writer(*syms)
+    options = syms.last.is_a?(Hash) ? syms.pop : {}
     syms.each do |sym|
       class_eval <<-EOS
         def self.#{sym}=(obj)
           write_inheritable_array(:#{sym}, obj)
         end
 
+        #{"
         def #{sym}=(obj)
           self.class.#{sym} = obj
         end
+        " unless options[:instance_writer] == false }
       EOS
     end
   end
 
   def class_inheritable_hash_writer(*syms)
+    options = syms.last.is_a?(Hash) ? syms.pop : {}
     syms.each do |sym|
       class_eval <<-EOS
         def self.#{sym}=(obj)
           write_inheritable_hash(:#{sym}, obj)
         end
 
+        #{"
         def #{sym}=(obj)
           self.class.#{sym} = obj
         end
+        " unless options[:instance_writer] == false }
       EOS
     end
   end
diff --git a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
index fe4f8a4fc0..8127150a96 100644
--- a/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
+++ b/activesupport/lib/active_support/core_ext/module/attribute_accessors.rb
@@ -3,6 +3,7 @@
 class Module # :nodoc:
   def mattr_reader(*syms)
     syms.each do |sym|
+      next if sym.is_a?(Hash)
       class_eval(<<-EOS, __FILE__, __LINE__)
         unless defined? @@#{sym}
           @@#{sym} = nil
@@ -20,6 +21,7 @@ class Module # :nodoc:
   end
   
   def mattr_writer(*syms)
+    options = syms.last.is_a?(Hash) ? syms.pop : {}
     syms.each do |sym|
       class_eval(<<-EOS, __FILE__, __LINE__)
         unless defined? @@#{sym}
@@ -29,10 +31,12 @@ class Module # :nodoc:
         def self.#{sym}=(obj)
           @@#{sym} = obj
         end
-
+        
+        #{"
         def #{sym}=(obj)
           @@#{sym} = obj
         end
+        " unless options[:instance_writer] == false }
       EOS
     end
   end
diff --git a/activesupport/test/core_ext/class/attribute_accessor_test.rb b/activesupport/test/core_ext/class/attribute_accessor_test.rb
new file mode 100644
index 0000000000..8104c9ce88
--- /dev/null
+++ b/activesupport/test/core_ext/class/attribute_accessor_test.rb
@@ -0,0 +1,31 @@
+require File.dirname(__FILE__) + '/../../abstract_unit'
+
+class ClassAttributeAccessorTest < Test::Unit::TestCase
+  def setup
+    @class = Class.new do
+      cattr_accessor :foo
+      cattr_accessor :bar, :instance_writer => false
+    end
+    @object = @class.new
+  end
+  
+  def test_should_use_mattr_default
+    assert_nil @class.foo
+    assert_nil @object.foo
+  end
+  
+  def test_should_set_mattr_value
+    @class.foo = :test
+    assert_equal :test, @object.foo
+  
+    @object.foo = :test2
+    assert_equal :test2, @class.foo
+  end
+  
+  def test_should_not_create_instance_writer
+    assert @class.respond_to?(:foo)
+    assert @class.respond_to?(:foo=)
+    assert @object.respond_to?(:bar)
+    assert !@object.respond_to?(:bar=)
+  end
+end
\ No newline at end of file
diff --git a/activesupport/test/class_inheritable_attributes_test.rb b/activesupport/test/core_ext/class/class_inheritable_attributes_test.rb
index f3c09f0516..8b11e680af 100644
--- a/activesupport/test/class_inheritable_attributes_test.rb
+++ b/activesupport/test/core_ext/class/class_inheritable_attributes_test.rb
@@ -1,4 +1,4 @@
-require File.dirname(__FILE__) + '/abstract_unit'
+require File.dirname(__FILE__) + '/../../abstract_unit'
 
 class ClassInheritableAttributesTest < Test::Unit::TestCase
   def setup
@@ -20,6 +20,14 @@ class ClassInheritableAttributesTest < Test::Unit::TestCase
       assert_respond_to @klass.new, :a=
     end
   end
+  
+  def test_writer_declaration_without_instance_writer
+    assert_nothing_raised do
+      @klass.class_inheritable_writer :a, :instance_writer => false
+      assert_respond_to @klass, :a=
+      assert !@klass.new.respond_to?(:a=)
+    end
+  end
 
   def test_accessor_declaration
     assert_nothing_raised do
@@ -30,6 +38,16 @@ class ClassInheritableAttributesTest < Test::Unit::TestCase
       assert_respond_to @klass.new, :a=
     end
   end
+  
+  def test_accessor_declaration_without_instance_writer
+    assert_nothing_raised do
+      @klass.class_inheritable_accessor :a, :instance_writer => false
+      assert_respond_to @klass, :a
+      assert_respond_to @klass.new, :a
+      assert_respond_to @klass, :a=
+      assert !@klass.new.respond_to?(:a=)
+    end
+  end
 
   def test_array_declaration
     assert_nothing_raised do
@@ -41,6 +59,16 @@ class ClassInheritableAttributesTest < Test::Unit::TestCase
     end
   end
 
+  def test_array_declaration_without_instance_writer
+    assert_nothing_raised do
+      @klass.class_inheritable_array :a, :instance_writer => false
+      assert_respond_to @klass, :a
+      assert_respond_to @klass.new, :a
+      assert_respond_to @klass, :a=
+      assert !@klass.new.respond_to?(:a=)
+    end
+  end
+
   def test_hash_declaration
     assert_nothing_raised do
       @klass.class_inheritable_hash :a
@@ -51,6 +79,16 @@ class ClassInheritableAttributesTest < Test::Unit::TestCase
     end
   end
 
+  def test_hash_declaration_without_instance_writer
+    assert_nothing_raised do
+      @klass.class_inheritable_hash :a, :instance_writer => false
+      assert_respond_to @klass, :a
+      assert_respond_to @klass.new, :a
+      assert_respond_to @klass, :a=
+      assert !@klass.new.respond_to?(:a=)
+    end
+  end
+
   def test_reader
     @klass.class_inheritable_reader :a
     assert_nil @klass.a
diff --git a/activesupport/test/core_ext/module/attr_accessor_with_default.rb b/activesupport/test/core_ext/module/attr_accessor_with_default.rb
new file mode 100644
index 0000000000..8ae52ad17a
--- /dev/null
+++ b/activesupport/test/core_ext/module/attr_accessor_with_default.rb
@@ -0,0 +1,30 @@
+require File.dirname(__FILE__) + '/../../abstract_unit'
+
+class AttrWithDefaultTest < Test::Unit::TestCase
+  def setup
+    @target = Class.new do
+      def helper
+        'helper'
+      end
+    end  
+    @instance = @target.new
+  end
+  
+  def test_default_arg
+    @target.attr_accessor_with_default :foo, :bar
+    assert_equal(:bar, @instance.foo)
+    @instance.foo = nil
+    assert_nil(@instance.foo)
+  end
+  
+  def test_default_proc
+    @target.attr_accessor_with_default(:foo) {helper.upcase}
+    assert_equal('HELPER', @instance.foo)
+    @instance.foo = nil
+    assert_nil(@instance.foo)
+  end
+  
+  def test_invalid_args
+    assert_raise(RuntimeError) {@target.attr_accessor_with_default :foo}
+  end
+end
\ No newline at end of file
diff --git a/activesupport/test/core_ext/module/attribute_accessor_test.rb b/activesupport/test/core_ext/module/attribute_accessor_test.rb
new file mode 100644
index 0000000000..c3f6575f84
--- /dev/null
+++ b/activesupport/test/core_ext/module/attribute_accessor_test.rb
@@ -0,0 +1,33 @@
+require File.dirname(__FILE__) + '/../../abstract_unit'
+
+class ModuleAttributeAccessorTest < Test::Unit::TestCase
+  def setup
+    @module = Module.new do
+      mattr_accessor :foo
+      mattr_accessor :bar, :instance_writer => false
+    end
+    @class = Class.new
+    @class.send :include, @module
+    @object = @class.new
+  end
+  
+  def test_should_use_mattr_default
+    assert_nil @module.foo
+    assert_nil @object.foo
+  end
+  
+  def test_should_set_mattr_value
+    @module.foo = :test
+    assert_equal :test, @object.foo
+  
+    @object.foo = :test2
+    assert_equal :test2, @module.foo
+  end
+  
+  def test_should_not_create_instance_writer
+    assert @module.respond_to?(:foo)
+    assert @module.respond_to?(:foo=)
+    assert @object.respond_to?(:bar)
+    assert !@object.respond_to?(:bar=)
+  end
+end
\ No newline at end of file