Add `exact` config option

lib/capybara.rb

@@ -16,7 +16,7 @@ module Capybara
 
   class << self
     attr_accessor :asset_root, :app_host, :run_server, :default_host, :always_include_port
-    attr_accessor :server_host, :server_port
+    attr_accessor :server_host, :server_port, :exact
     attr_accessor :default_selector, :default_wait_time, :ignore_hidden_elements
     attr_accessor :save_and_open_page_path, :automatic_reload
     attr_writer :default_driver, :current_driver, :javascript_driver, :session_name

lib/capybara/query.rb

@@ -11,6 +11,10 @@ module Capybara
         @options[:visible] = Capybara.ignore_hidden_elements
       end
 
+      unless options.has_key?(:exact)
+        @options[:exact] = Capybara.exact
+      end
+
       if args[0].is_a?(Symbol)
         @selector = Selector.all[args[0]]
         @locator = args[1]
@@ -27,7 +31,6 @@ module Capybara
         @xpath = @xpath.to_s
       end
 
-
       assert_valid_keys!
     end
 

lib/capybara/spec/session/find_spec.rb

@@ -127,7 +127,12 @@ Capybara::SpecHelper.spec '#find' do
     end
 
     it "defaults to `Capybara.exact`" do
-
+      Capybara.exact = true
+      expect do
+        @session.find(:xpath, XPath.descendant(:input)[XPath.attr(:id).is("est_fiel")])
+      end.to raise_error(Capybara::ElementNotFound)
+      Capybara.exact = false
+      @session.find(:xpath, XPath.descendant(:input)[XPath.attr(:id).is("est_fiel")])
     end
   end
 

lib/capybara/spec/spec_helper.rb

@@ -19,6 +19,7 @@ module Capybara
         Capybara.app_host = nil
         Capybara.default_selector = :xpath
         Capybara.default_wait_time = 1
+        Capybara.exact = false
       end
 
       def filter(requires, metadata)