add cucumber for integration testing and add a feature for statistics

refactor some stuff to support testing statistisc

features/step_definitions/todo_steps.rb

@@ -0,0 +1,31 @@
+Given /^I have no todos$/ do
+  Todo.delete_all
+end
+
+Given /^I have ([0-9]+) todos$/ do |count|
+  context = @current_user.contexts.create!(:name => "context A")
+  count.to_i.downto 1 do |i|
+    @current_user.todos.create!(:context_id => context.id, :description => "todo #{i}")
+  end
+end
+
+Given /^I have ([0-9]+) deferred todos$/ do |count|
+  context = @current_user.contexts.create!(:name => "context B")
+  count.to_i.downto 1 do |i|
+    @current_user.todos.create!(:context_id => context.id, :description => "todo #{i}", :show_from => @current_user.time + 1.week)
+  end
+end
+
+Given /^I have ([0-9]+) completed todos$/ do |count|
+  context = @current_user.contexts.create!(:name => "context C")
+  count.to_i.downto 1 do |i|
+    todo = @current_user.todos.create!(:context_id => context.id, :description => "todo #{i}")
+    todo.complete!
+  end
+end
+
+Then /^I should see ([0-9]+) todos$/ do |count|
+  count.to_i.downto 1 do |i|
+    match_xpath "div["
+  end
+end