py3: factor out helpers to apply string conversion recursively

py3: replace "if ispy3" by pycompat.sysbytes() or util.forcebytestr()

py3: replace "if ispy3" by pycompat.bytestr()

py3: replace "if ispy3" by encoding.strtolocal()

localrepo: drop the deprecated walk() method (API) .. api:: The deprecated localrepo.walk() has been removed, and replaced by repo[node].walk().

dirstate: drop deprecated methods (API) .. api:: beginparentchange() and endparentchange() have been replaced by the parentchange context manager.

templatekw: drop the deprecated '{troubles}' keyword

obsutil: drop deprecated methods (API) .. api:: The following deprecated methods have been removed from obsutil: marker.precnode() and allprecursors(). Use marker.prednode() and allpredecessors() instead.

revset: drop deprecated evolution predicates

obsolete: drop deprecated methods (API) .. api:: The following deprecated methods have been removed from obsolete, with replacements: - _addprecursors() -> _addpredecessors() - obsstore.precursors -> obsstore.predecessors - allprecursors() -> obsutil.allprecursors() - allsuccessors() -> obsutil.allsuccessors() - marker() -> obsutil.marker - getmarkers() -> obsutil.getmarkers() - exclusivemarkers() -> obsutil.exclusivemarkers() - foreground() -> obsutil.foreground() - successorssets() -> obsutil.successorsset() - unstable() -> orphan() - bumped() -> phasedivergent() - divergent() -> contentdivergent()

context: drop deprecated methods (API) .. api:: The following deprecated methods have been removed from context, with replacements: - unstable() -> orphan() - bumped() -> phasedivergent() - divergent() -> contentdivergent() - troubled() -> isunstable() - troubles() -> instabilities()

ui: improve performance for multi-component writes It is more efficient to pass down one large string to the output streams than many small ones. For a ``hg diff`` test case, it improves time from 2m26s to 2m8s. Differential Revision: https://phab.mercurial-scm.org/D1939

cmdutil: drop aliases for logcmdutil functions (API) .. api:: Log-related utility functions has been renamed as follows: - cmdutil.loglimit -> logcmdutil.getlimit - cmdutil.diffordiffstat -> logcmdutil.diffordiffstat - cmdutil._changesetlabels -> logcmdutil.changesetlabels - cmdutil.changeset_printer -> logcmdutil.changesetprinter - cmdutil.jsonchangeset = logcmdutil.jsonchangeset - cmdutil.changeset_templater -> logcmdutil.changesettemplater - cmdutil.logtemplatespec -> logcmdutil.templatespec - cmdutil.makelogtemplater -> logcmdutil.maketemplater - cmdutil.show_changeset -> logcmdutil.changesetdisplayer - cmdutil.getlogrevs -> logcmdutil.getrevs - cmdutil.getloglinerangerevs -> logcmdutil.getlinerangerevs - cmdutil.displaygraph -> logcmdutil.displaygraph - cmdutil.graphlog -> logcmdutil.graphlog - cmdutil.checkunsupportedgraphflags -> logcmdutil.checkunsupportedgraphflags - cmdutil.graphrevs -> logcmdutil.graphrevs - cmdutil._makenofollowlogfilematcher -> logcmdutil._makenofollowfilematcher

logcmdutil: drop redundant "log" from function names (API) A few exceptions: - s/loglimit/getlimit/ to avoid name conflict - s/_logrevs/_initialrevs/ to clarify its functionality

logcmdutil: rename classes and functions to conform to our coding style (API) show_changeset is renamed to changesetdisplayer as its return value is called a displayer.

cmdutil: split functions of log-like commands to new module (API) cmdutil.py is painfully big and makes Emacs slow. Let's split log-related functions. % wc -l mercurial/cmdutil.py 4027 mercurial/cmdutil.py % wc -l mercurial/cmdutil.py mercurial/logcmdutil.py 3141 mercurial/cmdutil.py 933 mercurial/logcmdutil.py 4074 total

httppeer: remove support for connecting to <0.9.1 servers (BC) Previously, HTTP wire protocol clients would attempt a "capabilities" wire protocol command. If that failed, they would fall back to issuing a "between" command. The "capabilities" command was added in Mercurial 0.9.1 (released July 2006). The "between" command has been present for as long as the wire protocol has existed. So if the "between" command failed, it was safe to assume that the remote could not speak any version of the Mercurial wire protocol. The "between" fallback was added in 395a84f78736 in 2011. Before that changeset, Mercurial would *always* issue the "between" command and would issue "capabilities" if capabilities were requested. At that time, many connections would issue "capabilities" eventually, so it was decided to issue "capabilities" by default and fall back to "between" if that failed. This saved a round trip when connecting to modern servers while still preserving compatibility with legacy servers. Fast forward ~7 years. Mercurial servers supporting "capabilities" have been around for over a decade. If modern clients are connecting to <0.9.1 servers, they are getting a bad experience. They may even be getting bad data (an old server is vulnerable to numerous security issues and could have been p0wned, leading to a Mercurial repository serving backdoors or other badness). In addition, the fallback can harm experience for modern servers. If a client experiences an intermittent HTTP request failure (due to bad network, etc) and falls back to a "between" that works, it would assume an empty capability set and would attempt to communicate with the repository using a very ancient wire protocol. Auditing HTTP logs for hg.mozilla.org, I did find a handful of requests for the null range of the "between" command. However, requests can be days apart. And when I do see requests, they come in batches. Those batches seem to correlate to spikes of HTTP 500 or other server/network events. So I think these requests are fallbacks from failed "capabilities" requests and not from old clients. If you need even more evidence to discontinue support, apparently we have no test coverage for communicating with servers not supporting "capabilities." I know this because all tests pass with the "between" fallback removed. Finally, server-side support for <0.9.1 pushing (the "addchangegroup" wire protocol command along with locking-related commands) was dropped from the HTTP client in fda0867cfe03 in 2017 and the SSH client in 9f6e0e7ef828 in 2015. I think this all adds up to enough justification for removing client support for communicating with servers not supporting "capabilities." So this commit removes that fallback. Differential Revision: https://phab.mercurial-scm.org/D2001

internals: document when "hello" and "capabilities" commands were added Both were introduced in 0.9.1. "hello" made its entrance in b17eebc911ae, 144280f1578f, and a1cfe679192c to support SSH. "capabilities" was added in c660691fb45d to support HTTP. Differential Revision: https://phab.mercurial-scm.org/D2000

tests: make doctest py3-compatible again A parsed tree is replaced with parse(expr) because it sucks to add b'' to every string literal.

lfs: emit a status message to indicate how many blobs were uploaded Previously, there was a progress bar indicating the byte count, but then it disappeared once the transfer was done. Having that value stay on the screen seems useful. Downloads are done one at a time, so hold off on that until they can be coalesced, to avoid a series of lines being printed. (I don't have any great ideas on how to do that. It would be a shame to have to wrap a bunch of read commands to be able to do this.) I'm not sure if the 'lfs:' prefix is the right thing to do here. The others in the test are verbose/debug messages, so in the normal case, this is the only line that's prefixed.

lfs: drop an unused function parameter

discovery: don't reimplement all() Differential Revision: https://phab.mercurial-scm.org/D1993

contrib: fix dirstatenonnormalcheck to work in Python 3 This is a redo of D1963 that has the added benefit of not breaking Python 2. Oops. # skip-blame because this is bytes prefixes and a s/iteritems/items/ Differential Revision: https://phab.mercurial-scm.org/D1970

python3: whitelist another 24 passing tests Differential Revision: https://phab.mercurial-scm.org/D1911

mdiff: use slice instead of index on bytestr when checking single bytes This is portable to Python 3. Differential Revision: https://phab.mercurial-scm.org/D1992

obsutil: work around filter() being a generator in Python 3 Differential Revision: https://phab.mercurial-scm.org/D1910

cmdutil: add a kludge to make bytes repr() the same on 2 and 3 This fixes the output formatting problems I see in debugobsolete. I still am seeing some effectflag differences, which we'll need to tackle separately. I'm not in love with this approach. There might be something better we could do, and I'd love it if someone else wanted to take a run at this. Differential Revision: https://phab.mercurial-scm.org/D1909

wireprotoserver: make name part of protocol interface This is a required part of the interface. Abstract properties must be defined at type creation time. So we make name a @property. Differential Revision: https://phab.mercurial-scm.org/D1991

wireprotoserver: make abstractserverproto a proper abstract base class Plug in the abc module so we can have run-time validation of type conformance. Differential Revision: https://phab.mercurial-scm.org/D1990

wireprotoserver: make response handling attributes private The send* methods are specific to sshserver and aren't part of the common protocol interface. So rename them accordingly. The handlers dict is also specific to sshserver and is related to these methods. So give it the same treatment. Differential Revision: https://phab.mercurial-scm.org/D1989