exchange: send bundle2 stream clones uncompressed Stream clones don't compress well. And compression undermines a point of stream clones which is to trade significant CPU reductions by increasing size. Building upon our introduction of metadata to communicate bundle information back to callers of exchange.getbundlechunks(), we add an attribute to the bundler that communicates whether the bundle is best left uncompressed. We return this attribute as part of the bundle metadata. And the wire protocol honors it when determining whether to compress the wire protocol response. The added test demonstrates that the raw result from the wire protocol is not compressed. It also demonstrates that the server will serve stream responses when the feature isn't enabled. We'll address that in another commit. The effect of this change is that server-side CPU usage for bundle2 stream clones is significantly reduced by removing zstd compression. For the mozilla-unified repository: before: 37.69 user 8.01 system after: 27.38 user 7.34 system Assuming things are CPU bound, that ~10s reduction would translate to faster clones on the client. zstd can decompress at >1 GB/s. So the overhead from decompression on the client is small in the grand scheme of things. But if zlib compression were being used, the overhead would be much greater. Differential Revision: https://phab.mercurial-scm.org/D1926

tests: update test to work with Git 2.16 It looks like Git 2.16 removed the "..." from some strings. Glob over those characters in the test output. Differential Revision: https://phab.mercurial-scm.org/D1935

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

convert: use a collections.deque This function was doing a list.pop(0) on a list whose length was the number of revisions to convert. Popping an early element from long lists is not an efficient operation. collections.deque supports efficient inserts and pops at both ends. So we switch to that data structure. When converting the mozilla-unified repository, which has 445,748 revisions, this change makes the "sorting..." step of `hg convert --sourcesort` significantly faster: before: ~59.2s after: ~1.3s Differential Revision: https://phab.mercurial-scm.org/D1934

repair: invalidate volatile sets after stripping Matt Harbison reported that some tests were broken on Windows after 1a09dad8b85a (evolution: report new unstable changesets, 2018-01-14). The failures were exactly as seen in this patch. The failures actually seemed correct, which made me wonder why they didn't fail the same way on Linux. It turned out to be a cache invalidation problem. The new orphan mentioned in the test case actually does get created when we're re-applying the temporary bundle that's created while stripping. However, without the invalidation, it appears that there was already an orphan before applying the temporary bundle. The warnings about unknown working parent appear because the aformentioned changeset means that we're now accessing the dirstate while it's invalid. We may want to suppress these messages that happen in the intermediate strip state, but they're technically correct (although confusing to the user), so I think just fixing the cache invalidation is fine for now. I haven't figured out why the caches seemed to get correctly invalidated on Windows. Differential Revision: https://phab.mercurial-scm.org/D1933

subrepo: handle 'C:' style paths on the command line (issue5770) If you think 'C:' and 'C:\' are equivalent paths, see the inline comment before proceeding. The problem here was that several commands that take a URL argument (incoming, outgoing, pull, and push) will use that value to set 'repo._subtoppath' on the repository object after command specific manipulation of it, but before converting it to an absolute path. When an operation is performed on a relative subrepo, subrepo._abssource() will posixpath.join() this value with the relative subrepo path. That adds a '/' after the drive letter, changing how it is evaluated by abspath()/realpath() in vfsmod.vfs(..., realpath=True) as the subrepo is instantiated. I initially tried sanitizing the path in url.localpath(), because url.isabs() only checks that it starts with a drive letter. By the sample behavior, this is clearly not an absolute path. (Though the comment in isabs() is weasely- this style path can't be joined either.) But not everything funnels through there, and it required explicitly calling localpath() in hg.parseurl() and assigning to url.path to fix. But then tests failed with urls like 'a#0'. Next up was sanitizing the path in the url constructor. That caused doctest failures, because there are drive letter tests, so those got expanded in system specific ways. Yuya correctly pointed out that util.url is a parser, and shouldn't be substituting the path too. Rather than fixing every command call site, just convert it in the common subrepo location. I don't see any sanitizing on the path config options, so I fixed those too. Note that while the behavior is fixed here, there are still places where 'comparing with C:' gets printed out, and that's not great for debugging purposes. (Specifically I saw it in `hg incoming -B C:`, without subrepos.) While clone will write out an absolute default path, I wonder what would happen if a user edited that path to be 'C:'. (I don't think supporting relative paths in .hgrc is a sane thing to do, but while we're poking holes in things...) Since this is such an oddball case, it still leaks through in places, and there seems to be a lot of duplicate url parsing, maybe the url parsing should be moved to dispatch, and provide the command with a url object? Then we could convert this to an absolute path once, and not have to worry about it in the rest of the code. I also checked '--cwd C:' on the command line, and it was previously working because os.chdir() will DTRT. Finally, one other note from the url.localpath() experimenting. I don't see any cases where 'self._hostport' can hold a drive letter. So I'm wondering if that is wrong/old code.

dummysmtpd: don't die on client connection errors The connection refused error in test-patchbomb-tls.t[1] is sporadic, but one of the more often seen errors on Windows. I added enough logging to a file and dumped it out at the end to make the following observations: - The listening socket is successfully created and bound to the port, and the "listening at..." message is always logged. - Generally, the following is the entire log output, with the "accepted ..." message having been added after `sslutil.wrapserversocket`: listening at localhost:$HGPORT $LOCALIP ssl error accepted connect accepted connect $LOCALIP from=quux to=foo, bar $LOCALIP ssl error - In the cases that fail, asyncore.loop() in the run() method is exiting, but not with an exception. - In the cases that fail, the following is logged right after "listening ...": Traceback (most recent call last): File "c:\\Python27\\lib\\asyncore.py", line 83, in read obj.handle_read_event() File "c:\\Python27\\lib\\asyncore.py", line 443, in handle_read_event self.handle_accept() File "../tests/dummysmtpd.py", line 80, in handle_accept conn = sslutil.wrapserversocket(conn, ui, certfile=self._certfile) File "..\\mercurial\\sslutil.py", line 570, in wrapserversocket return sslcontext.wrap_socket(sock, server_side=True) File "c:\\Python27\\lib\\ssl.py", line 363, in wrap_socket _context=self) File "c:\\Python27\\lib\\ssl.py", line 611, in __init__ self.do_handshake() File "c:\\Python27\\lib\\ssl.py", line 840, in do_handshake self._sslobj.do_handshake() error: [Errno 10054] $ECONNRESET$ - If the base class handler is overridden completely, the the first "ssl error" line is replaced by the stacktrace, but the other lines are unchanged. The client behaves no differently, whether or not the server stacktraced. In general, `./run-tests.py --local -j9 -t9000 test-patchbomb-tls.t --runs-per-test 20` would show the issue after a run or two. With this change, `./run-tests.py --local -j9 -t9000 test-patchbomb-tls.t --loop` ran 800 times without a hiccup. This makes me wonder if the other connection refused messages that bubble up on occasion are caused by a similar issue. It seems a bit drastic to kill the whole server on account of a single communication failure with a client. # no-check-commit because of handle_error() [1] https://buildbot.mercurial-scm.org/builders/Win7%20x86_64%20hg%20tests/builds/421/steps/run-tests.py%20%28python%202.7.13%29/logs/stdio