Add test for 308 redirect

lib/capybara/spec/session/click_button_spec.rb

@@ -396,9 +396,14 @@ Capybara::SpecHelper.spec '#click_button' do
     expect(@session.current_url).to match(%r{/landed$})
   end
 
-  it "should follow redirects that maintain method" do
+  it "should follow temporary redirects that maintain method" do
     @session.click_button('Go 307')
-    expect(@session).to have_content('You post landed: 307')
+    expect(@session).to have_content('You post landed: TWTW')
+  end
+
+  it "should follow permanent redirects that maintain method" do
+    @session.click_button('Go 308')
+    expect(@session).to have_content('You post landed: TWTW')
   end
 
   it "should post pack to the same URL when no action given" do

lib/capybara/spec/test_app.rb

@@ -42,6 +42,10 @@ class TestApp < Sinatra::Base
     redirect '/landed', 307
   end
 
+  post '/redirect_308' do
+    redirect '/landed', 308
+  end
+
   get '/referer_base' do
     '<a href="/get_referer">direct link</a>' \
     '<a href="/redirect_to_get_referer">link via redirect</a>' \

lib/capybara/spec/views/form.erb

@@ -552,12 +552,13 @@ New line after and before textarea tag
   <p>
     <input type="submit" value="Go FAR"/>
   </p>
-</form>
 
-<form action="/redirect_307" method="post">
-  <input type="hidden" name="form[data]" value="307"/>
+  <input type="hidden" name="form[data]" value="TWTW"/>
   <p>
-    <input type="submit" value="Go 307"/>
+    <button formaction='/redirect_307'>Go 307</button>
+  </p>
+  <p>
+    <button formaction='/redirect_308'>Go 308</button>
   </p>
 </form>