httppeer: use util.readexactly() to abort on incomplete responses Plain resp.read(n) may not return exactly n bytes when we need, and to detect such cases before trying to interpret whatever has been read, we can use util.readexactly(), which raises an Abort when stream ends unexpectedly. In the first case here, readexactly() prevents a traceback with struct.error, in the second it avoids looking for invalid compression engines. In this test case, _wraphttpresponse doesn't catch the problem (presumably because it doesn't know transfer encoding), and the code continues reading the response until it gets to compression engine data. Maybe there should be checks before the execution gets there, but I'm not sure where (httplib?)

httppeer: calculate total expected bytes correctly User-facing error messages that handled httplib.IncompleteRead errors in Mercurial used to look like this: abort: HTTP request error (incomplete response; expected 3 bytes got 1) But the errors that are being handled underneath the UI look like this: IncompleteRead(1 bytes read, 3 more expected) I.e. the error actually counts total number of expected bytes minus bytes already received. Before, users could see weird messages like "expected 10 bytes got 10", while in reality httplib expected 10 _more_ bytes (20 in total).

lazyancestors: reuse __iter__ implementation in __contains__ There was a comment in the code that said "Trying to do both __iter__ and __contains__ using the same visit heap and seen set is complex enough that it slows down both. Keep them separate.". However, it seems easy and efficient to make __contains__ keep an iterator across calls. I couldn't measure any slowdown from `hg bundle --all` (which seem to call lazyancestors.__contains__ frequently). Differential Revision: https://phab.mercurial-scm.org/D4508

lazyancestors: extract __iter__ to free function The next patch will keep a reference to the returned iterator in a field, which would otherwise result in a reference cycle. Differential Revision: https://phab.mercurial-scm.org/D4517

phase: report number of non-public changeset alongside the new range When interacting with non-publishing repository or bundle, it is useful to have some information about the phase of the changeset we just pulled. This changeset updates the "new changesets MIN:MAX" output to also includes phases information for non-public changesets. Displaying extra data about non-public changesets means the output for exchange with publishing repository (the default) is unaffected.

tests: disable test-nointerrupt on Windows Per the followup discussion[1]. proc.send_signal(INT) in timeout.py raises a ValueError because of an unsupported signal. I don't like missing test coverage for this on Windows. But this is the last test failing on Windows, and red all the time hides new failures. [1] https://phab.mercurial-scm.org/D3716

tests: conditionalize an error message about unlinking a non empty directory The message on Windows comes from win32.unlink(). It looks like os.unlink() on posix platforms is a simple call to unlink(3), which turns into unlinkat(2). Since there's a comment in one of the tests that the message should be improved, I don't think it's worth adding a check in win32.unlink() to see if it's empty, if that function is always going to fail on a directory. (It seems like the POSIX spec allows unlinking directories though.)

ancestors: add nullrev to set from the beginning Differential Revision: https://phab.mercurial-scm.org/D4507