pager: recreate stdout to make it line-buffered We want to see partial command results as soon as possible. But the buffering mode of stdout (= pager's stdin) was set to fully-buffered because it isn't associated with a tty. So, this patch recreates new stdout object to force its buffering mode. Because two file objects are associated with the same stdout fd and their destructors will call close(), one of them must be closed carefully. Python expects that the stdout fd never be closed even after sys.stdout.close() [1], but newstdout has no such hack. So this patch calls newstdout.close() immediately before duplicating the original stdout fd to sys.stdout. operation sys.stdout newstdout fd --------------------- ---------- --------- -------- newstdout.close() open closed closed os.dup2(stdoutfd, ..) open closed open del sys.stdout closed closed open [1] [1]: https://hg.python.org/cpython/file/v2.7.10/Python/sysmodule.c#l1391

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# progress.py show progress bars for some actions

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#

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# Copyright (C) 2010 Augie Fackler <durin42@gmail.com>

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#

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# This software may be used and distributed according to the terms of the

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# GNU General Public License version 2 or any later version.

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"""show progress bars for some actions (DEPRECATED)

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This extension has been merged into core, you can remove it from your config.

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See hg help config.progress for configuration options.

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"""

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# Note for extension authors: ONLY specify testedwith = 'internal' for

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# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should

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# be specifying the version(s) of Mercurial they are tested with, or

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# leave the attribute unspecified.

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testedwith = 'internal'