This tests against a bug that was triggered by incorrectly remembering link
integrity breaches due to removing and re-adding all of them and when changing
a linking content item.  As this will only happen in a specific situation,
namely when some items are removed from a container object containing an
Archetypes "TextField", we need a bit of setup first.  The bug was discovered
using the "RichDocument" product, but Plone's "Collection" luckily also has
the required properties:

  >>> self.setRoles(('Manager',))
  >>> portal.portal_properties.site_properties.disable_folder_sections = True
  >>> topic = portal[portal.invokeFactory('Topic', id='topic', title='a topic',
  ...   text='<html> <body> a somewhat interesting topic </body> </html>')]
  >>> portal.topic.unmarkCreationFlag()
  >>> topic.invokeFactory('Topic', id='subtopic1', title='a subtopic',
  ...   text='<html> <body> a boring subtopic </body> </html>')
  'subtopic1'
  >>> portal.topic.subtopic1.unmarkCreationFlag()
  >>> topic.invokeFactory('Topic', id='subtopic2', title='another subtopic',
  ...   text='<html> <body> another boring subtopic </body> </html>')
  'subtopic2'
  >>> portal.topic.subtopic2.unmarkCreationFlag()

So we have a "collection" or "topic", which contains two subtopics.  Now we
refer to these as well as an image outside of the "collection":

  >>> self.setText(topic, """
  ...   <a href="../image1">an image</a>
  ...   <a href="subtopic1">a boring subtopic</a>
  ...   <a href="subtopic2">another boring subtopic</a> """)

Then we try to delete the subtopics which triggers a `IObjectModifiedEvent`
on the topic and therefore causes it to recalculate its link integrity
references.  This used to first remove all references and then determine and
set the current ones by searching for links contained in the items rendered
content.  Doing so would in turn trigger a removal event for the reference
representing the link to the image, i.e. an item that is not supposed to be
removed.  Nevertheless the event handler added this link to the list of link
integrity breaches.

Before we can test the fix for the bug we need to prevent the test framework
from choking on the exception we intentionally throw as usual (see
`docs/testRemovalTriggersConfirmation.txt` for more info).  Also, we need to
work around a bug, which causes none of the action buttons to appear in the
"subfolders" tab of the topic, including the required "delete" button.  To
work around this we call the `manage_delObjects` method directly, passing in
the ids of the selected items:

  >>> self.setStatusCode('LinkIntegrityNotificationException', 200)
  >>> browser = self.getBrowser(loggedIn=True)
  >>> browser.open('http://nohost/plone/topic/atct_topic_subtopics')
  >>> browser.getControl('a subtopic').selected = True
  >>> browser.getControl('another subtopic').selected = True

Normally the test would continue by clicking the "delete" button, i.e.
using `>>> browser.getControl('Delete').click()`, but we need to work around
the missing buttons as explained above.  We also need to explicitly indicate
the number of to be removed objects, which is normally taken care of in the
`delete_folder` script:

  >>> from os.path import basename
  >>> paths = browser.getControl(name='paths:list').value
  >>> qs = 'ids:list=' + '&ids:list='.join(map(basename, paths))
  >>> qs += '&link_integrity_events_to_expect:int=%s' % len(paths)
  >>> browser.open('manage_delObjects?' + qs)

We should now get a link integrity confirmation page warning us about the
two subtopics, but only about these two.  The referenced image shouldn't be
listed:

  >>> browser.contents
  '...<a href="http://nohost/plone/topic/subtopic1"...a subtopic...
   ...This...Topic...is referenced by the following items:...
   ...<li>...href="http://nohost/plone/topic"...a topic...</li>...
   ...<a href="http://nohost/plone/topic/subtopic2"...another subtopic...
   ...This...Topic...is referenced by the following items:...
   ...<li>...href="http://nohost/plone/topic"...a topic...</li>...
   ...Would you like to delete it anyway?...'
  >>> len(browser.contents.split('is referenced by the following items'))
  3
  >>> 'Test Image 1' in browser.contents
  False
  >>> browser.getLink('Test Image 1')
  Traceback (most recent call last):
  ...
  LinkNotFoundError

