[MERGE] Nuke versioned file add/get delta support, allowing easy simplification of unannotated Content, reducing memory copies and friction during commit on unannotated texts.

[Martin Pool]

Martin Pool has voted tweak.
Status is now: Conditionally approved
Comment:

+class ExistingContent(BzrError):
+
+    """Added in bzrlib 0.92, used by VersionedFile.add_lines."""

The first line of the docstring ought to tell what this *is*, and that
doesn't.  Can you please add something before saying what this exception
means?


+class PlainKnitContent(KnitContent):
+    """Unannotated content."""
+

This has the special behaviour of, when annotated, claiming that 
everything
came from a single version.  That seems like quite a nice facility
but you should really say that's what happens.

+        # Technically this is a case of LBYL, but:

Please expand the acronym; you can capitalize the phrase if you want.



-class KnitContentTests(TestCase):
+class KnitContentTestsMixin(object):

I would kind of prefer that you change these to scenarios instead, but I
don't insist on it.


For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3C1189031297.27465.2.camel%40lifeless-64%3E