outgoing: rework the handling of the `missingroots` case to be faster The previous implementation was slow, to the point it was taking a significant amount of `hg bundle --type none-streamv2` call. We rework the code to compute the same value much faster, making the operation disappear from the `hg bundle --type none-streamv2` profile. Someone would remark that producing a streamclone does not requires an `outgoing` object. However that is a matter for another day. There is other user of `missingroots` (non stream `hg bundle` call for example), and they will also benefit from this rework. We implement an old TODO in the process, directly computing the missing and common attribute as we have most element at hand already. ### benchmark.name = hg.command.bundle # bin-env-vars.hg.flavor = default # bin-env-vars.hg.py-re2-module = default # benchmark.variants.revs = all # benchmark.variants.type = none-streamv2 ## data-env-vars.name = heptapod-public-2024-03-25-zstd-sparse-revlog before: 7.750458 after: 6.665565 (-14.00%, -1.08) ## data-env-vars.name = mercurial-public-2024-03-22-zstd-sparse-revlog before: 0.700229 after: 0.496050 (-29.16%, -0.20) ## data-env-vars.name = mozilla-try-2023-03-22-zstd-sparse-revlog before: 346.508952 after: 316.749699 (-8.59%, -29.76) ## data-env-vars.name = pypy-2024-03-22-zstd-sparse-revlog before: 3.401700 after: 2.915810 (-14.28%, -0.49) ## data-env-vars.name = tryton-public-2024-03-22-zstd-sparse-revlog before: 1.870798 after: 1.461583 (-21.87%, -0.41) note: this whole `missingroots` of outgoing has a limited number of callers and could likely be replace by something simpler (like taking an explicit "missing_revs" set for example). However this is a wider change and we focus on a small impact, quick rework that does not change the API for now.

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# scmutil.py - Mercurial core utility functions

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#

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#  Copyright Olivia Mackall <olivia@selenic.com> and other

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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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from . import repoview

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def cachetocopy(srcrepo):

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    """return the list of cache file valuable to copy during a clone"""

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    # In local clones we're copying all nodes, not just served

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    # ones. Therefore copy all branch caches over.

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    cachefiles = [b'branch2']

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    cachefiles += [b'branch2-%s' % f for f in repoview.filtertable]

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    cachefiles += [b'branch3']

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    cachefiles += [b'branch3-%s' % f for f in repoview.filtertable]

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    cachefiles += [b'rbc-names-v1', b'rbc-revs-v1']

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    cachefiles += [b'tags2']

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    cachefiles += [b'tags2-%s' % f for f in repoview.filtertable]

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    cachefiles += [b'hgtagsfnodes1']

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    return cachefiles