py3: avoid use of basestring "In this case, result is a source variable of a list to be returned, it shouldn't be unicode. Hence we can use bytes instead of basestring here." -Yuya

py3: use unicodes in __slots__ __slots__ in Python 3 accepts only unicodes and there is no harm using unicodes in __slots__. So just adding u'' is fine. Previous occurences of this problem are treated the same way.

memctx: allow the metadataonlyctx thats reusing the manifest node When we have a lot of files writing a new manifest revision can be expensive. This commit adds a possibility for memctx to reuse a manifest from a different commit. This can be beneficial for commands that are creating metadata changes without any actual files changed like "hg metaedit" in evolve extension. I will send the change for evolve that leverages this once this is accepted.

localrepo: make it possible to reuse manifest when commiting context This makes the commit function understand the context that's reusing manifest.

manifest: expose the parents() method

httppeer: assign Vary request header last In preparation for adding another value to it in a subsequent patch. While I was here, I added some empty lines because walls of text are hard to read.