wireproto: move version 2 command handlers to wireprotov2server This is relatively straightforward. As part of this, we introduced a local @wireprotocommand that wraps the main one and defines a v2 only policy by default. Because the hacky HTTPv2 peer isn't using capabilities response yet, we had to move some code around to force import of wireprotov2server so commands are registered. This is super hacky. But this code will go away once the HTTPv2 peer is using the capabilities response to derive permissions. Differential Revision: https://phab.mercurial-scm.org/D3231

wireproto: extract HTTP version 2 code to own module wireprotoserver has generic and version 1 server code. The wireproto module also has both version 1 and version 2 command implementations. Upcoming work I want to do will make it difficult for this code to live in the current locations. Plus, it kind of makes sense for the version 2 code to live in an isolated module. This commit copies the HTTPv2 bits from wireprotoserver into a new module. We do it as a file copy to preserve history. A future commit will be copying wire protocol commands into this module as well. But there is little history of that code, so it makes sense to take history for wireprotoserver. Differential Revision: https://phab.mercurial-scm.org/D3230

wireproto: client reactor support for receiving frames We can now feed received frames into the client reactor and it will validate their sanity, dispatch them appropriately. The hacky HTTP peer has been updated to use the new code. No existing tests changed, somewhat proving the code works as expected. Rudimentary unit tests for the new functionality have been implemented. Differential Revision: https://phab.mercurial-scm.org/D3224

wireproto: introduce a reactor for client-side state We have a nice state machine of sorts for reacting to server-side events. Now it is time to implement the client equivalent. We introduce a "clientreactor." It allows callers to request that commands be issued. It has multiple modes of operation to reflect what the underlying transport supports. e.g. for SSH, we can perform wire sends immediately but for HTTP we need to buffer sends until all command requests are received. In addition, SSH allows sending multiple requests as long as the connection is open. But HTTP/1.1 only allows sending request data once. For SSH, we'll have one reactor per connection. For HTTP, we'll have one reactor per HTTP request. But because code that calls wire protocol commands should not be aware of how the underlying transport works, this will all be abstracted away by the peer interface. Our crude HTTP peer has been updated to use the reactor instead of formulating frames directly. No behavior should have changed here and tests seem to confirm that. Basic unit tests for the reactor behavior have been added. Differential Revision: https://phab.mercurial-scm.org/D3223

tests: extract wire protocol framing tests to own file I was lazy when I put these in test-wireproto-serverreactor.py. Let's do it properly. Differential Revision: https://phab.mercurial-scm.org/D3222

wireproto: disallow commands handlers for multiple transport versions I think it will be more trouble than it is worth to code version 1 and version 2 command handlers to the same interface. It will feel awkward to shoehorn functionality into e.g. the version 1 protocol handler interface. This would likely constrain the ability for version 2 to evolve. Previous commits introduced a clean separation between command handlers for version 1 and version 2 transports. This commit reinforces that separation by dropping support for having a single command handler service both version 1 and version 2 transports. Differential Revision: https://phab.mercurial-scm.org/D3208

wireproto: make @wireprotocommand version 1 only by default For backwards compatibility reasons. We want extension provided commands to opt in to version 2 rather than get inherited automatically. This will facilitate a clean break between the protocols. As part of this, we duplicate some commands used in tests so there are different command handlers per transport. Differential Revision: https://phab.mercurial-scm.org/D3207

wireproto: only expose "getbundle" and "unbundle" to v1 transports These are the most complicated wire protocol commands. I don't want to deal with porting them just yet. Let's disable both of them on version 2 transports so we drive the final wedge between command handlers and start to evolve version 2 command handlers more. Differential Revision: https://phab.mercurial-scm.org/D3206

wireproto: port lookup to wire protocol v2 This is pretty straightforward. We don't yet handle errors because we don't have an error handling mechanism in place yet. I'm also tempted to fold this into `known`. We'll come back to this later. Differential Revision: https://phab.mercurial-scm.org/D3205

wireproto: port pushkey command to wire protocol version 2 It doesn't do output redirection yet. And I'd love to generally overhaul the pushkey protocol for wire protocol version 2. But this will be a bit of effort. Let's do it as a follow-up. Differential Revision: https://phab.mercurial-scm.org/D3204

wireproto: only expose "clonebundles" to version 1 transports This may make a comeback in wire protocol version 2. The feature definitely needs to be carried forward. But at this juncture, I'm flirting with the idea of implementing this via a "redirect" mechanism at the command response level itself rather than something that requires one-off client support for querying and handling. i.e. I want to make it so servers can say "fetch this first and then come back" and clients handle that automatically. This would not only support clone bundles, but would also support piece-meal "pull bundles." Whatever happens, we can deal with it down the road. Differential Revision: https://phab.mercurial-scm.org/D3203

wireproto: define and expose types of wire command arguments Exposing the set of argument names is cool. But with wire protocol version 2, we're using CBOR to transport arguments and this allows us to have typing for arguments. Typed arguments are much nicer because they will cut down on transfer overhead and processing overhead for decoding values. This commit teaches @wireprotocommand to accept a dictionary for arguments. The arguments registered for version 2 transports are canonically stored as dictionaries rather than a space-delimited string. It is an error to defined arguments with a dictionary for commands using version 1 transports. This reinforces my intent to fully decouple command handlers for version 2 transports. Differential Revision: https://phab.mercurial-scm.org/D3202

wireproto: only expose "stream_out" to version 1 transports I have plans to implement stream clone using a better mechanism than this existing command. Let's not carry it forward to wire protocol version 2. Differential Revision: https://phab.mercurial-scm.org/D3201

wireproto: implement capabilities for wire protocol v2 The capabilities mechanism for wire protocol version 2 represents a clean break from version 1. Instead of effectively exchanging a set of capabilities, we're exchanging a rich data structure. This data structure currently contains information about every available command, including its accepted arguments. It also contains information about supported compression formats. Exposing information about supported commands will allow clients to automatically generate bindings to the server. Clients will be able to do things like detect when they are attempting to run a command that isn't known to the server. Exposing the required permissions to run a command can be used by clients to determine if they have privileges to call a command before actually calling it. We could potentially even have clients send credentials preemptively without waiting for the server to deny the command request. Lots of potential here. The data returned by this command will likely evolve heavily. So we shouldn't bikeshed the implementation just yet. Differential Revision: https://phab.mercurial-scm.org/D3200

context: add deprecation warnings for deprecated types of changeids It's close to code freeze, and dropping support for repo['123'] and repo ['my-bookmark'] and repo['deadbeef'] is pretty dispruptive, so this just adds deprecation warnings so extensions can easily find the places they need to fix. Differential Revision: https://phab.mercurial-scm.org/D3197

revsymbol: stop delegating to repo.__getitem__ for unhandled symbols (API) The only remaining cases where we were delegating unhandled symbols to repo.__getitem__ should now be when the symbol could not be found. In that case we just delegated to repo.__getitem__ for the error message. Let's just copy the error message instead. If there were any cases where we got e.g. a binary nodeid or an integer revnum into revsymbol() (e.g. via repo.lookup()), we'd now start raising an exception instead. That is why this is marked (API). This affects one test case, but the new behavior seems better to me. I can't tell if the old behavior was desired or if the test was just there to document how it happened to work. Differential Revision: https://phab.mercurial-scm.org/D3196

context: handle partial nodeids in revsymbol() Similar reasoning as previous patches. Differential Revision: https://phab.mercurial-scm.org/D3195

context: handle namespaces in revsymbol() Similar reasoning as previous patches. Differential Revision: https://phab.mercurial-scm.org/D3194

scmutil: handle full hex nodeids in revsymbol() This is a bit unfortunate, but it enables moving other pieces out of changectx's constructor without affecting the order in which we look up things (e.g. hex nodeid before bookmark). We convert nodeid to revnum before calling repo.__getitem__, even though that will result in converting back to nodeid later. This is so we can handle the LookupError and attempt to interpret the string as something else (e.g. a bookmark). We also need to start handling WdirUnsupported now, since the full hex nodeid "ffff..." represents the working directory. The exception is raised by the revlog layer. Differential Revision: https://phab.mercurial-scm.org/D3193

context: handle stringified ints in revsymbol() This patch copies the handling of stringified ints from changectx's constructor. It then calls repo.__getitem__ with the int. Since that method only interprets integers as revnums the first thing it does, this will not be redoing any of the work already done. We leave the old code in place so we can later deprecate it instead of breaking extensions. Differential Revision: https://phab.mercurial-scm.org/D3146

py3: make sure we write bytes to file # skip-blame because just b'' prefix Differential Revision: https://phab.mercurial-scm.org/D3220

py3: workaround comparing NoneType and integers Comparing None with integers was fine in Python 2 but returns error in Python 3 which is nice. This patch replaces None with -1 where sorting is done and some related logic. Differential Revision: https://phab.mercurial-scm.org/D3219

py3: use sys.stdout instead of print in test-mq-qpush-fail.t Differential Revision: https://phab.mercurial-scm.org/D3218

py3: use '//' for integer division in tests/test-mq-qimport.t Differential Revision: https://phab.mercurial-scm.org/D3217