Element no longer connected to DOM

description

Found by Dima Kovalenko

Selenium specs which call "wait for element to be visible" fail on an "Element no longer connected to DOM" error.

The problem occurs when the div appears briefly, then goes away. If the loop exits after the div is already off the screen, the call to "wait for element to be visible times out, and causes the spec to fail.

This issue can be elusive, only failing intermittently because sometimes the loop exits quickly enough to avoid producing the error. The fact that the div is displayed then hidden was the key to identifying and solving this bug in our test.

diff.rb

--- a/features/support/env.rb
+++ b/features/support/env.rb
@@ -345,12 +345,15 @@ module Ajax
 
   def wait_until_updated_element_is_visible(css_selector)
     page.should have_css(css_selector)
-    page.wait_until do
+    page.wait_until 20 do
+      visible = nil
       if all(css_selector).empty?
-        false
+        visible = false
       else
-        all(css_selector).first.visible?
+        visible = all(css_selector).first.visible?
       end
+      puts "waiting.."
+      visible
     end
   end
 end

slightly less ugly diff

diff --git a/features/support/env.rb b/features/support/env.rb
index 54f753f..809b8d1 100644
--- a/features/support/env.rb
+++ b/features/support/env.rb
@@ -346,10 +346,11 @@ module Ajax
def wait_until_updated_element_is_visible(css_selector)
page.should have_css(css_selector)
page.wait_until do

•  if all(css_selector).empty?
  

•    false
  

•  selectors = all(css_selector)
  

•  if selectors.empty?
  

•    return false
  

  else

•    all(css_selector).first.visible?
  

•    return selectors.first.visible?
  

  end
  end
  end