Added has_button?

lib/capybara/session.rb

@@ -177,6 +177,14 @@ module Capybara
       has_no_xpath?(XPath.link(locator))
     end
 
+    def has_button?(locator)
+      has_xpath?(XPath.button(locator))
+    end
+
+    def has_no_button?(locator)
+      has_no_xpath?(XPath.button(locator))
+    end
+
     def has_field?(locator, options={})
       has_xpath?(XPath.field(locator, options))
     end

spec/dsl/has_button_spec.rb

@@ -0,0 +1,32 @@
+shared_examples_for "has_button" do  
+  describe '#has_button?' do
+    before do
+      @session.visit('/form')
+    end
+
+    it "should be true if the given button is on the page" do
+      @session.should have_button('med')
+      @session.should have_button('crap321')
+    end
+
+    it "should be false if the given button is not on the page" do
+      @session.should_not have_button('monkey')
+    end
+  end
+
+  describe '#has_no_button?' do
+    before do
+      @session.visit('/form')
+    end
+
+    it "should be true if the given button is on the page" do
+      @session.should_not have_no_button('med')
+      @session.should_not have_no_button('crap321')
+    end
+
+    it "should be false if the given button is not on the page" do
+      @session.should have_no_button('monkey')
+    end
+  end
+end
+

spec/session_spec.rb

@@ -53,6 +53,7 @@ shared_examples_for "session" do
   it_should_behave_like "has_css"
   it_should_behave_like "has_xpath"
   it_should_behave_like "has_link"
+  it_should_behave_like "has_button"
   it_should_behave_like "has_field"
   it_should_behave_like "select"
   it_should_behave_like "uncheck"