This tests customerizeability (phew :)) of views and viewlets registered for
a specific layer using `plone.browserlayer`.  Most of the test's setup and
actual code or text was borrowed from that package as well, but let's get
started...

In `testing.zcml` we have registered a view, "layer-test-view", available only
for the layer `plone.app.customerize.tests.interfaces.IMyLayer`. Before the
product is installed, we cannot view the view, though:

  >>> from plone.app.customerize.tests.interfaces import IMyLayer
  >>> from plone.browserlayer.utils import register_layer, registered_layers
  >>> IMyLayer in registered_layers()
  False
  >>> import transaction

  >>> browser = self.site_administrator_browser
  >>> browser.handleErrors = False
  >>> browser.open('http://nohost/plone/@@layer-test-view')
  Traceback (most recent call last):
  ...
  NotFound:   <h2>Site Error</h2>
  ...

We can view a view registered for the default layer, though:

  >>> browser.open('http://nohost/plone/@@standard-test-view')
  >>> print browser.contents
  a standard view

At this time only the latter should be customerizable:

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.contents
  '...Plone View Customizations...
   ...The following list shows all registered...
   ...<a href="@@customizezpt.html?...view_name=standard-test-view"...
   ...>standard-test-view</a>...'
  >>> 'layer-test-view' in browser.contents
  False

However, if we install the product both views should be traversable and both
should also show up as being customizable:

  >>> register_layer(IMyLayer, name='my.product')
  >>> IMyLayer in registered_layers()
  True
  >>> transaction.commit()

  >>> browser.open('http://nohost/plone/@@layer-test-view')
  >>> print browser.contents
  a local view

  >>> browser.open('http://nohost/plone/@@standard-test-view')
  >>> print browser.contents
  a standard view

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.contents
  '...Plone View Customizations...
   ...The following list shows all registered...
   ...<a href="@@customizezpt.html?...view_name=layer-test-view"...
   ...>layer-test-view</a>...
   ...<a href="@@customizezpt.html?...view_name=standard-test-view"...
   ...>standard-test-view</a>...'

The layer is unregistered again to clean up for the remainder of the test:

  >>> from plone.browserlayer.utils import unregister_layer
  >>> unregister_layer(name='my.product')
  >>> IMyLayer in registered_layers()
  False

The same should be true for viewlets.  First we need to set them up via the
GenericSetup profile provided for testing, after which the standard viewlet
should show up on the home page:

  >>> from Products.CMFCore.utils import getToolByName
  >>> portal_setup = getToolByName(self.portal, 'portal_setup')
  >>> _ = portal_setup.runAllImportStepsFromProfile('profile-plone.app.customerize.tests:testing')
  >>> transaction.commit()

  >>> browser.open('http://nohost/plone/')
  >>> browser.contents
  '...id="portal-logo"...
   ...a standard view...
  >>> 'a local view' in browser.contents
  False

The standard viewlet should be customizable, but not the local one:

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.contents
  '...Plone View Customizations...
   ...The following list shows all registered...
   ...<a href="@@customizezpt.html?...view_name=standard-test-viewlet"...
   ...>standard-test-viewlet</a>...'
  >>> 'layer-test-viewlet' in browser.contents
  False

Again, the layer is registered and now both viewlets should show up on the
home page and as being customizable:

  >>> register_layer(IMyLayer, name='my.product')
  >>> transaction.commit()
  >>> IMyLayer in registered_layers()
  True

  >>> browser.open('http://nohost/plone/')
  >>> browser.contents
  '...id="portal-logo"...
   ...a local view...a standard view...

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.contents
  '...Plone View Customizations...
   ...The following list shows all registered...
   ...<a href="@@customizezpt.html?...view_name=layer-test-viewlet"...
   ...>layer-test-viewlet</a>...
   ...<a href="@@customizezpt.html?...view_name=standard-test-viewlet"...
   ...>standard-test-viewlet</a>...'

We still need to make sure the local view and viewlet can actually be
customerized.  First we look at the info page for the view:

  >>> browser.getLink('layer-test-view').click()
  >>> browser.contents
  '...The following is the source of...layer-test-view...
   ...<dl>...
   ...view name...layer-test-view...
   ...registered for interface...zope.interface.Interface...
   ...registered for request type...plone.app.customerize.tests.interfaces.IMyLayer...
   ...template file...plone.app.customerize.tests/local.pt...
   ...zcml file...plone.app.customerize.tests/testing.zcml...
   ...</dl>...
   ...<pre>...a local view</pre>...'

We click the "customize" button, enter some new content, and save the changes:

  >>> browser.handleErrors = True
  >>> browser.getControl('Customize').click()
  >>> browser.url
  'http://nohost/plone/portal_view_customizations/zope.interface.interface-layer-test-view/pt_editForm'
  >>> browser.getControl(name='text:text').value = """<tal:block define="dummy python:request.response.setHeader('Content-Type', 'text/plain')" />customized view"""
  >>> browser.getControl('Save Changes').click()
  >>> browser.url
  'http://nohost/plone/portal_view_customizations/zope.interface.interface-layer-test-view'
  >>> browser.contents
  '...Saved changes...'

  Now we look at the view we just customized:

  >>> browser.open('http://nohost/plone/@@layer-test-view')
  >>> print browser.contents
  customized view

And now let's do the same with a viewlet:

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.getLink('layer-test-viewlet').click()
  >>> browser.contents
  '...The following is the source of...layer-test-viewlet...
   ...<dl>...
   ...view name...layer-test-viewlet...
   ...registered for interface...zope.interface.Interface...
   ...registered for request type...plone.app.customerize.tests.interfaces.IMyLayer...
   ...template file...plone.app.customerize.tests/local.pt...
   ...zcml file...plone.app.customerize.tests/testing.zcml...
   ...</dl>...
   ...<pre>...a local view</pre>...'
   >>> browser.getControl('Customize').click()
   >>> browser.url
   'http://nohost/plone/portal_view_customizations/zope.interface.interface-layer-test-viewlet/pt_editForm'
   >>> browser.getControl(name='text:text').value = 'customized viewlet'
   >>> browser.getControl('Save Changes').click()
   >>> browser.url
   'http://nohost/plone/portal_view_customizations/zope.interface.interface-layer-test-viewlet'
   >>> browser.contents
   '...Saved changes...'
   >>> browser.open('http://nohost/plone/@@layer-test-view')
   >>> browser.open('http://nohost/plone/')
   >>> browser.contents
   '...id="portal-logo"...
    ...customized viewlet...

Let's double-check the information for a viewlet on the default layer
(this is to demonstrate issue #8275 which arises to do improper handling
of portlet templates).

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.getLink('standard-test-viewlet').click()
  >>> browser.contents
  '...The following is the source of...standard-test-viewlet...
   ...<dl>...
   ...view name...standard-test-viewlet...
   ...registered for interface...zope.interface.Interface...
   ...registered for request type...zope.publisher.interfaces.browser.IDefaultBrowserLayer...
   ...template file...plone.app.customerize.tests/standard.pt...
   ...zcml file...plone.app.customerize.tests/testing.zcml...
   ...</dl>...
   ...<pre>...a standard view</pre>...'

And clean up after ourselves for the sake of later tests:

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.getLink('Contents').click()
  >>> browser.getControl(name='ids:list').getControl(value='zope.interface.interface-layer-test-view').selected = True
  >>> browser.getControl(name='ids:list').getControl(value='zope.interface.interface-layer-test-viewlet').selected = True
  >>> browser.getControl('Delete').click()
  >>> browser.url
  'http://nohost/plone/portal_view_customizations/'
  >>> browser.contents
  '...There are currently no items in...'

As a last test to make sure the extension_ for browserlayer awareness
doesn't have any unwanted side effects, we compare the list of registrations
with the layer registered and not.  The set difference should come down to
only the locally registered view and viewlet:

  >>> from plone.app.customerize.registration import templateViewRegistrations
  >>> IMyLayer in registered_layers()
  True
  >>> with_layer = set([ reg.name for reg in templateViewRegistrations() ])
  >>> unregister_layer(name='my.product')
  >>> IMyLayer in registered_layers()
  False
  >>> without_layer = set([ reg.name for reg in templateViewRegistrations() ])
  >>> without_layer.issubset(with_layer)
  True
  >>> sorted(list(with_layer.difference(without_layer)))
  ['layer-test-view', u'layer-test-viewlet']

  .. _extension: http://dev.plone.org/plone/changeset/20088

Let's do a test to show that if two browser layers register a viewlet with the
same name, we can customize both of them. We have registered a second viewlet.
Let's register it for both layers:

  >>> from plone.app.customerize.tests.interfaces import IOtherLayer
  >>> register_layer(IMyLayer, name='my.product')
  >>> register_layer(IOtherLayer, name='my.otherproduct')
  >>> transaction.commit()

Now we should see two registrations with this view name:

  >>> browser.open('http://nohost/plone/portal_view_customizations/registrations.html')
  >>> browser.contents
  '...Plone View Customizations...
   ...The following list shows all registered...
   ...<a href="@@customizezpt.html?...view_name=layer-test-viewlet"...
   ...>layer-test-viewlet</a>...
   ...<a href="@@customizezpt.html?...view_name=layer-test-viewlet"...
   ...>layer-test-viewlet</a>...'

But they should link to different places:

  >>> my = browser.getLink('layer-test-viewlet', index=0)
  >>> other = browser.getLink('layer-test-viewlet', index=1)
  >>> my.text == other.text
  True
  >>> my.url == other.url
  False