[MERGE] repository external reference tests (StackedBranches)

[Martin Pool]

Martin Pool has voted tweak.
Status is now: Resubmit
Comment:
> bzrlib/tests/repository_external_reference_implementations/__init__.py

This is almost 80 chars just for the module name, maybe a smaller name 
is possible?

+"""Repository implementation tests for external reference repositories.
+
+These test the conformance of repositories which refer to other 
repositories
+for some data.
+"""

It'd be worth mentioning these are run for all repositories that support 
references.

+    adapter.scenarios = []
+    for scenario in scenarios:
+        format = scenario[1]['repository_format']

I guess 'scenario' here is a tuple of several things; it'd be better to 
unpack it in the for statement and avoid indexing later if possible.

+def load_tests(standard_tests, module, loader):

The boilerplate in here is meant to be avoided by
multiply_tests_from_modules, I really dislike the way it's 
proliferating.
But it looks like it would not be trivial to change it back, and there
might be an interaction with vila's changes.  Maybe it's best left for
another patch.

On the other hand well done for splitting out
all_repository_format_scenarios so that it can be reused like this.

+        unused_repo = repo.bzrdir.open_repository()

But it is used...

Is this meant to be creating another object looking at the same
repository?  Maybe a comment about intent would be good.

Otherwise it seems to make sense.


For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C48474354.1040103%40canonical.com%3E