revset-_ancestor: use & instead of filter The & operation is more likely optimised. ::10 before) wall 0.028189 comb 0.030000 user 0.030000 sys 0.000000 (best of 100) after) wall 0.001050 comb 0.000000 user 0.000000 sys 0.000000 (best of 2326) ::tip before) wall 0.081132 comb 0.080000 user 0.080000 sys 0.000000 (best of 100) after) wall 0.055418 comb 0.050000 user 0.050000 sys 0.000000 (best of 100)

obsstore: record data as floating point in fm0 format For python struct module, "d" is double. But for python string formating, "d" is integer. We want to preserve the floating point nature of the data, so we store it in the metadata as floating point. We use "%r" to make sure we get as many significant digitis as necessary to restore the float to the exact same value on the other side. The fm1 is transmitting the information as float. The lack of this made fm1-stored markers not survive a round-trip to fm0 leading to duplicated markers (or two markers very alike).

bundle2: add a comment about addchangegroup source and url

pull: call the `b2x-transactionclose` hook when closing the transaction We need a wider set of hooks to process all the changes that happened during the pull transaction. We reuse the experimental `b2x-transactionclose` hook set from server's unbundle for consistency. This hook is experimental and will not remains as-is forever, but this will open the door for experimentation in 3.2.

revset-only: use __nonzero__ to check if a revset is empty For some smartsets, computing length is more expensive than checking if the set is empty.

_spanset: drop __getitem__ implementation It is expensive and not part of the official smartset API.

filteredset: drop __getitem__ implementation It is expensive and not part of the official smartset API.

generatorset: implement __len__ It was the only smartset class without a `__len__` implementation.

revset: make __len__ part of the offical API It is common for code to ask for the length of a revset. In fact, all but generatorset already implement it.

cmdserver: add service that listens on unix domain socket and forks process Typical use case of 'unix' mode is a background hg daemon. $ hg serve --cmdserver unix --cwd / -a /tmp/hg-`id -u`.sock Unlike 'pipe' mode in which parent process keeps stdio channel, 'unix' server can be detached. So clients can freely connect and disconnect from server, saving Python start-up time. It might be better to write "--cmdserver socket -a unix:/sockpath" instead of "--cmdserver unix -a /sockpath" in case hgweb gets the ability to listen on unix domain socket.