branchcache: skip entries that are topological heads in the on disk file In the majority of cases, topological heads are also branch heads. We have efficient way to get the topological heads and efficient way to retrieve their branch information. So there is little value in putting them in the branch cache file explicitly. On the contrary, writing them explicitly tend to create very large cache file that are inefficient to read and update. So the branch cache v3 format is no longer including them. This changeset focus on the format aspect and have no focus on the performance aspect. We will cover that later.

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# __init__.py - Startup and module loading logic for Mercurial.

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#

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# Copyright 2015 Gregory Szorc <gregory.szorc@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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# Allow 'from mercurial import demandimport' to keep working.

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import hgdemandimport

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demandimport = hgdemandimport