wireprotov2: define response data as CBOR Previously, response data was defined as a stream of bytes. We had the option to declare it as CBOR using a frame flag. We've converged all wire protocol commands exposed on version 2 to CBOR. I think consistency is important. The overhead to encoding things with CBOR is minimal. Even a very large bytestring can be efficiently encoded using an indefinite length bytestring. Now, there are limitations with consumers not being able to efficiently stream large CBOR values. But these feel like solvable problems. This commit removes the "is CBOR" frame flag from command response frames and defines the frame as always consisting of a stream of CBOR values. The framing protocol media type has been bumped to reflect this BC change. Differential Revision: https://phab.mercurial-scm.org/D3382

wireprotov2: decode responses to their expected types Callers of established wire protocol commands expect the response from that command to be decoded into a data structure. It's not very useful if callers get back a stream of bytes and don't know how they should be interpreted - especially since that stream of bytes varies by wire protocol and even the transport within that protocol version. This commit establishes decoding functions for various command responses so callers of those commands get the response type they expect. In theory, this should make the version 2 HTTP peer usable for various operations. But I haven't tested to confirm. Differential Revision: https://phab.mercurial-scm.org/D3381

wireprotov2: establish a type for representing command response It will be desirable to have a higher-level type for representing command responses. This will allow us to do nicer things. For now, the instance encapsulates existing logic. It is still a bit primitive. But we're slowly making things better. Version 1 protocols have a wrapping layer that decodes the raw string data into a data structure and that data structure is sent to the future. Version 2 doesn't yet have this layer and the future is receiving the raw wire response. Hence why debugcommands needed to be taught about the response type. Differential Revision: https://phab.mercurial-scm.org/D3380