exchange: return bundle info from getbundlechunks() (API) We generally want a mechanism to pass information about the generated bundle back to callers (in addition to the byte stream). Ideally we would return a bundler from this function and have the caller code to an interface. But the bundling APIs are not great and getbundlechunks() is the best API we have for obtaining bundle contents in a unified manner. We change getbundlechunks() to return a dict that we can use to communicate metadata. We populate that dict with the bundle version number to demonstrate some value. .. api:: exchange.getbundlechunks() now returns a 2-tuple instead of just an iterator. Differential Revision: https://phab.mercurial-scm.org/D1925

exchange: make stream bundle part deterministic repo.requirements is a set. We need to sort it so the part content is deterministic. Differential Revision: https://phab.mercurial-scm.org/D1924

bundle2: specify what capabilities will be used for We currently assume there is a symmetric relationship of bundle2 capabilities between client and server. However, this may not always be the case. We need a bundle2 capability to advertise bundle2 streaming clone support on servers to differentiate it from the existing, legacy streaming clone support. However, servers may wish to disable streaming clone support. If bundle2 capabilities were the same between client and server, a client (which may also be a server) that has disabled streaming clone support would not be able to perform a streaming clone itself! This commit introduces a "role" argument to bundle2.getrepocaps() that explicitly defines the role being performed. This will allow us (and extensions) to alter bundle2 capabilities depending on the operation being performed. Differential Revision: https://phab.mercurial-scm.org/D1923

wireproto: don't compress errors from getbundle() Errors should be small. There's no real need to compress them. Truth be told, there's no good reason to not compress them either. But leaving them uncompressed makes it easier to test failures by looking at the raw HTTP response. This makes it easier for us to write tests. It may make it easier for people writing their own clients. Differential Revision: https://phab.mercurial-scm.org/D1922

tests: teach get-with-headers.py some new tricks We add the ability to specify arbitrary HTTP request headers and to save the HTTP response body to a file. These will be used in upcoming commits. Differential Revision: https://phab.mercurial-scm.org/D1921

tests: use argparse in get-with-headers.py I'm about to add another flag and I don't want to deal with this organic, artisanal argument parser. Differential Revision: https://phab.mercurial-scm.org/D1920