rebase: extra default destination in its own function This makes it much simple to wrap for other extension.

revset: rename and test '_destmerge' We make the name consistent with the one used by '_destupdate' and we ensure the code is run by testing it (abort is expected and merge would).

merge: directly get destination from destutil There is no real value in using the revset over the function. The revset have no remaining users and will be taken care of in a later changesets.

destutil: move default merge destination into a function Function in destutil are much simpler to wrap and more flexible than revset. This also help consistency as 'destupdate' live here and cannot become a pure revset anyway.

revset: reintroduce and experimental revset for update destination The revset is not ready for prime time yet. However it is useful to have some version of it exposed to help candidate users to play with it and provide feedback on what we should aim at. We add a small test to make sure the code runs.

changegroup: move manifest unpacking into its own method The upcoming cg3 will need different logic for unpacking manifests.

changegroup: move manifest packing into a separate function A future change will introduce a new function on a cg3packer that can pack treemanifests as well as flatmanifests.

changegroup: rename manifest linknode closure for clarity Since I'm spending the time to understand this code, I may as well leave it clearer than I found it.

changegroup: reformat packermap and add comment I'm about to add a cg3, and it seems prudent to annotate what formats support what features. It strikes me that we may want to consider moving to a more feature-oriented model in the future, but we'll see how that looks in a little while I guess.

changegroup: document the public surface area of cg?unpackers This should help future readers at least a little.

changegroup: mark cg1unpacker.chunklength as private

changegroup: note why a few methods on cg1unpacker exist I'm not sure what to do abstraction-wise here. It might be more sensible to make a memoryrepo that could apply a bundle in-memory and then we could make the changegroup data be strictly an applyable stream, but that's an idea for Later.

revlog: rename bundle to cg to reflect its nature as a cg?unpacker The new convention is that bundles contain changegroups. bundle1 happens to *only* be a changegroup, but bundle2 is a more featureful container that isn't something you can pass to addgroup().

changegroup: mark _addchangegroupfiles as module-private I'm trying to reason about the public surface area of this module now, so it's worth tagging private things as such.

changegroup: delete now-unused addchangegroup method

localrepo: use cg?unpacker.apply() instead of changegroup.addchangegroup() This is in localpeer, so it lives. Had it been in localrepo instead, I would have tried to exterminate it.

repair: use cg?unpacker.apply() instead of changegroup.addchangegroup()

exchange: use cg?unpacker.apply() instead of changegroup.addchangegroup()

commands: use cg?unpacker.apply() instead of changegroup.addchangegroup()

bundle2: use cg?unpacker.apply() instead of changegroup.addchangegroup()

shelve: use cg?unpacker.apply() instead of changegroup.addchangegroup()

histedit: use cg?unpacker.apply() instead of changegroup.addchangegroup()

changegroup: migrate addchangegroup() to forward to cg?unpacker.apply() I'll clean up callers in subsequent patches, then remove the forwarding.

changegroup: move source check to top of addchangegroup This is preparation for some refactoring.

error: remove superfluous pass statements

hook: raise a separate exception for when loading a hook fails For easier catching.

clonebundles: advertise clone bundles feature to clients Server operators that have enabled clone bundles probably want clients to use it. This patch introduces a feature that will insert a bundle2 "output" part that advertises the existence of the clone bundles feature to clients that aren't using it. The server uses the "cbattempted" argument to "getbundle" to determine whether a client supports clone bundles and to avoid sending the message to clients that failed the clone bundle for whatever reason.

exchange: advertise if a clone bundle was attempted The client now sends a "cbattempted" boolean flag to the "getbundle" wire protocol command to tell the server whether a clone bundle was attempted. The presence of this flag will enable the server to conditionally emit a bundle2 "output" part advertising the availability of clone bundles to compatible clients that don't have it enabled.

exchange: record that we attempted to fetch a clone bundle This is needed so a subsequent patch can conditionally add a bundle2 part to the "getbundle" wire protocol command depending on whether a clone bundle was attempted.

exchange: provide hint on how to disable clone bundles If a clone bundle persistently fails to apply, users need a way to disable it so they have a hope of the clone working. Change the hint for the abort scenario to advertise the config option to disable clone bundles.