mercurial: Changelog

cext: split character encoding functions to new compilation unit This extracts charencode.c from parsers.c, which seems big enough for me to hesitate to add new JSON functions. Still charencode.o is linked to parsers.so to avoid duplication of binary codes.

cext: move _dict_new_presized() to header Prepares for splitting encoding functions from parsers.c.

ui: restore behavior to ignore some I/O errors (issue5658) e9646ff34d55 and 1bfb9a63b98e refactored ui methods to no longer silently swallow some IOError instances. This is arguably the correct thing to do. However, it had the unfortunate side-effect of causing StdioError to bubble up to sensitive code like transaction aborts, leading to an uncaught exceptions and failures to e.g. roll back a transaction. This could occur when a remote HTTP or SSH client connection dropped. The new behavior is resulting in semi-frequent "abandonded transaction" errors on multiple high-volume repositories at Mozilla. This commit effectively reverts e9646ff34d55 and 1bfb9a63b98e to restore the old behavior. I agree with the principle that I/O errors shouldn't be ignored. That makes this change... unfortunate. However, our hands are tied for what to do on stable. I think the proper solution is for the ui's behavior to be configurable (possibly via a context manager). During critical sections like transaction rollback and abort, it should be possible to suppress errors. But this feature would not be appropriate on stable.

tests: test behavior of IOError during transactions (issue5658) ui._write(), ui._write_err(), and ui.flush() all trap IOError and re-raise as error.StdioError. If a caller doesn't catch StdioError when writing to stdio, it could bubble all the way to dispatch. This commit adds tests for I/O failures around various transaction operations. The most notable badness is during abort. Here, an uncaught StdioError will result in incomplete transaction rollback, requiring an `hg rollback` to recover. This can result in a client "corrupting" a remote repo via terminated HTTP and SSH socket.

log: mention ui.logtemplate in the help text

hg: avoid relying on errno numbers / descriptions A few tests hardcode errno numbers and/or descriptions in the output, causing test failures on platforms where these values are different. Differential Revision: https://phab.mercurial-scm.org/D362

hg: tolerate long vs. int in test-context.py The file times here can be longs instead of ints on some platforms, which will cause a test failure due to these printing with an L suffix; instead always format with %d which will produce the same output in either case. Differential Revision: https://phab.mercurial-scm.org/D361