lfs: allow a pointer to be extracted from a context that removes the file This is needed to let 'set:lfs()' and '{lfs_files}' work normally on removed files. Yuya suggested returning a null pointer for removed files, instead of the pointer from the parent. The first attempt at this was to return None for a non LFS file, and a (pointer, ctx) tuple to hold the pointer and context (or parent pointer and context for a removed file). But this complicated the callers, even the ones that didn't care about removed files. Instead, let's use {} to represent a removed pointer. This has the added convenience of being a useful representation in the template language, and only affects the callers that care about removed files (and only slightly). Since pointers are explicitly serialized with a call to a member function, there is no danger of writing these to disk.

rebase: make "successors" a set in _computeobsoletenotrebased() There's no apparent reason for this variable to be a list and this avoids converting it to a set when needed.

merge with stable

rebase: do not consider extincts for divergence detection (issue5782) Extinct obsolete changesets cannot cause divergence upon rebase. We compute these obsoletes without a non-obsolete successor (extincts) in _computeobsoletenotrebased() and then filter them out from the set of obsolete revisions to rebase before getting into _checkobsrebase() to check for divergence candidates.

rebase: eliminate node from successors early in _computeobsoletenotrebased()

rebase: add a test case for issue5782 Issue 5782 reports that rebase incorrectly aborts when trying to rebase an extinct revision (an obsolete revision with only obsolete successor). We add a test to demonstrate this: the first "hg rebase" command aborts with the divergence warning while, when allowing divergence, the rebase completes and does not actually produce any divergence.

test: glob the temporary directory out of temporary file path The temporary directory used by python might be outside of '/tmp/' (eg: /dev/shm/) so we glob that part out.