Merge lp:~adeuring/launchpad/bug-507642 into lp:launchpad

This branch removes the properties IBug.subscriptions,
IBug.users_affected IBug.users_unaffected,
IBug.users_affected_with_dupes and IBug.messages from snapshots
of IBug objects.

It is at present impossible to (un)subscribe from bug 1 via AJAX.
(other manipulations of bug 1 via the webservice API like marking
oneself as being affected by this bug don't work either.) Attempts
to do that lead to OOPSes as reported in bug 507642, bug 505999,
bug 534339. They are caused because a snapshot of the bug involves
making shortlist instances of the above mentioned properties in
snapshot_sql_result(), and the hard limit for the shortlist is set
to 1000, while bug 1 has meanwhile more than 1000 comments.

It would have been enough to mark IBug.messages with doNotSnapshot(),
but bug 1 has ca 300 subscribers and ca 200 people feel affected by
it, and I think that these numbers are close enough to the hard limit
to remove the related properties from the snapshot too.

In order to trigger the failure, we need a bug with "too many" comments,
subscribers or affected people. Instead of creating 1000 bug comments
or people just for the tests, I changed the hard limit for the
shortlist() calls for the tests.

main test:

./bin/test -t test_bugs_webservice

possibly affected tests where snapshots of IBug objects are involved:

./bin/test -t test_bugtask -t test_bugnotification -t test_bugchanges

= Launchpad lint =

Checking for conflicts. and issues in doctests and templates.
Running jslint, xmllint, pyflakes, and pylint.
Using normal rules.

Linting changed files:
  lib/canonical/launchpad/webapp/snapshot.py
  lib/lp/bugs/interfaces/bug.py
  lib/lp/bugs/tests/test_bugs_webservice.py

== Pylint notices ==

lib/canonical/launchpad/webapp/snapshot.py
    11: [F0401] Unable to import 'lazr.lifecycle.interfaces' (No module named lifecycle)

lib/lp/bugs/interfaces/bug.py
    36: [F0401] Unable to import 'lazr.lifecycle.snapshot' (No module named lifecycle)
    52: [F0401] Unable to import 'lazr.restful.declarations' (No module named restful)
    58: [F0401] Unable to import 'lazr.restful.fields' (No module named restful)
    59: [F0401] Unable to import 'lazr.restful.interface' (No module named restful)
    506: [C0322, IBug.addAttachment] Operator not preceded by a space
    comment=Text(), filename=TextLine(), is_patch=Bool(),
    ^
    content_type=TextLine(), description=Text())
    @export_factory_operation(IBugAttachment, [])
    def addAttachment(owner, data, comment, filename, is_patch=False,
    content_type=None, description=None):
    653: [C0322, IBug.getNominations] Operator not preceded by a space
    nominations=List(
    ^
    title=_("Nominations to search through."),
    value_type=Reference(schema=Interface), # IBugNomination
    required=False))
    @operation_returns_collection_of(Interface) # IBugNomination
    @export_read_operation()
    def getNominations(target=None, nominations=None):
    733: [C0322, IBug.markUserAffected] Operator not preceded by a space
    required=False, default=True))
    ^
    @call_with(user=REQUEST_USER)
    @export_write_operation()
    def markUserAffected(user, affected=True):
    748: [C0322, IBug.setCommentVisibility] Operator not preceded by a space
    required=True),
    ^
    visible=Bool(title=_('Show this comment?'), required=True))
    @call_with(user=REQUEST_USER)
    @export_write_operation()
    def setCommentVisibility(user, comment_number, visible):
    760: [C0322, IBug.linkHWSubmission] Operator not preceded by a space
    Interface, title=_('A HWDB submission'), required=True))
    ^
    @export_write_operation()
    def linkHWSubmission(submission):
    767: [C0322, IBug.unlinkHWSubmission] Operator not preceded by a space
    Interface, title=_('A HWDB submission'), required=True))
    ^
    @export_write_operation()
    def unlinkHWSubmission(submission):