commit: add some help examples (issue4963) Includes documenting --date now, which resolves the above issue.

changegroup: restate file linknode callback using generator expressions I think this is slightly clearer, and it nicely avoids an extra nested function.

changegroup: clean up file lookup function One case is basically degenerate, so just extract it and make the function clearer.

changegroup: remove one special case from lookupmflinknode In the fastpathlinkrev case, lookupmflinknode was a very complicated way of saying mfs.__getitem__, so let's just get that case out of our way so it's easier to understand what's going on.

changegroup: drop 'if True' that made the previous change clearer

changegroup: avoid iterating the whole manifest The old code gathered the list of all files that changed anywhere in history and then gathered changed file nodes by walking the entirety of each manifest to be sent in order to gather changed file nodes. That's going to be unfortunate for narrowhg, and it's already inefficient for medium-to-large repositories. Timings for bundle --all on my hg repo, tested with hgperf: Before: ! wall 23.442445 comb 23.440000 user 23.250000 sys 0.190000 (best of 3) After: ! wall 20.272187 comb 20.270000 user 20.190000 sys 0.080000 (best of 3)

posix: work around "posix" systems without os.link available (issue4974) Some platforms (see bug, notably a terminal emulator on Android) ship with os.link removed from Python to try and cater to other tools that expect os.link to exist iff hardlinks are supported on that platform. As a workaround for this madness, include a fallback path for when we're on a "posix" platform but lack os.link.

pathutil: use temporary variables instead of complicated wrapping The one-lining did not help readability, we get rid of it.

context: use a the nofsauditor when matching file in history (issue4749) Before this change, asking for file from history (eg: 'hg cat -r 42 foo/bar') could fail because of the current content of the working copy (eg: current "foo" being a symlink). As the working copy state have no influence on the content of the history, we can safely skip these checks. The working copy context class have a different 'match' implementation. That implementation still use the repo.auditor will still catch symlink traversal. I've audited all stuff calling "match" and they all go through a ctx in a sensible way. The most unclear case was diff which still seemed okay. You raised my paranoid level today and I double checked through tests. They behave properly. The odds of someone using the wrong (matching with a changectx for operation that will eventually touch the file system) is non-zero because you are never sure of what people will do. But I dunno if we can fight against that. So I would not commit to "never" for "at this level" and "in the future" if someone write especially bad code. However, as a last defense, the vfs itself is running path auditor in all cases outside of .hg/. So I think anything passing the 'matcher' for buggy reason would growl at the vfs layer.

localrepo: add a second auditor without file system check Auditors keeps a cache of audited paths. Therefore we cannot use the same auditor for working copy and history operation. We create a new one without file system check for this purposes.