Allows passing options through has_button? to has_selector?

This enables assertions on the presence of disabled buttons by doing:

    assert has_button?('Button text', :disabled => true)

in a similar way to:

    find_field("Disabled Checkbox", :disabled => true)

lib/capybara/node/matchers.rb

@@ -280,8 +280,8 @@ module Capybara
       # @param [String] locator      The text, value or id of a button to check for
       # @return [Boolean]            Whether it exists
       #
-      def has_button?(locator)
+      def has_button?(locator, options={})
-        has_selector?(:button, locator)
+        has_selector?(:button, locator, options)
       end
 
       ##
@@ -292,8 +292,8 @@ module Capybara
       # @param [String] locator      The text, value or id of a button to check for
       # @return [Boolean]            Whether it doesn't exist
       #
-      def has_no_button?(locator)
+      def has_no_button?(locator, options={})
-        has_no_selector?(:button, locator)
+        has_no_selector?(:button, locator, options)
       end
 
       ##

lib/capybara/rspec/matchers.rb

@@ -126,8 +126,8 @@ module Capybara
       HaveSelector.new(:link, locator, options)
     end
 
-    def have_button(locator)
+    def have_button(locator, options={})
-      HaveSelector.new(:button, locator)
+      HaveSelector.new(:button, locator, options)
     end
 
     def have_field(locator, options={})

lib/capybara/spec/session/has_button_spec.rb

@@ -9,9 +9,21 @@ Capybara::SpecHelper.spec '#has_button?' do
     @session.should have_button(:'crap321')
   end
 
+  it "should be true for disabled buttons if :disabled => true" do
+    @session.should have_button('Disabled button', :disabled => true)
+  end
+
   it "should be false if the given button is not on the page" do
     @session.should_not have_button('monkey')
   end
+
+  it "should be false for disabled buttons by default" do
+    @session.should_not have_button('Disabled button')
+  end
+
+  it "should be false for disabled buttons if :disabled => false" do
+    @session.should_not have_button('Disabled button', :disabled => false)
+  end
 end
 
 Capybara::SpecHelper.spec '#has_no_button?' do
@@ -24,7 +36,19 @@ Capybara::SpecHelper.spec '#has_no_button?' do
     @session.should_not have_no_button('crap321')
   end
 
+  it "should be true for disabled buttons if :disabled => true" do
+    @session.should_not have_no_button('Disabled button', :disabled => true)
+  end
+
   it "should be false if the given button is not on the page" do
     @session.should have_no_button('monkey')
   end
+
+  it "should be false for disabled buttons by default" do
+    @session.should have_no_button('Disabled button')
+  end
+
+  it "should be false for disabled buttons if :disabled => false" do
+    @session.should have_no_button('Disabled button', :disabled => false)
+  end
 end