hgext/git/TODO.md
author Raphaël Gomès <rgomes@octobus.net>
Mon, 23 Mar 2020 12:07:45 +0100
changeset 44605 f451a347d21a
parent 44489 ad718271a9eb
child 44625 c5653cf2811d
permissions -rw-r--r--
rust: update micro-timer dependency The new version uses a much more robust technique and should remove any existing risk of bad compiler error or performance hit. Differential Revision: https://phab.mercurial-scm.org/D8319
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
44489
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     1
Octopus Merge Support
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     2
=====================
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     3
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     4
This will be moderately complicated, as we'll need to synthesize phony
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     5
changeset entries to explode the octopus into "revisions" that only
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     6
have two parents each. For today, we can probably just do something like
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     7
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     8
    aaaaaaaaaaaaaaaaaaXX{20 bytes of exploded node's hex sha}
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
     9
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    10
where XX is a counter (so we could have as many as 255 parents in a
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    11
git commit - more than I think we'd ever see.) That means that we can
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    12
install some check in this extension to disallow checking out or
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    13
otherwise interacting with the `aaaaaaaaaaaaaaaaaa` revisions.
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    14
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    15
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    16
Interface Creation
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    17
====================
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    18
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    19
We at least need an interface definition for `changelog` in core that
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    20
this extension can satisfy, and again for `basicstore`.
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    21
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    22
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    23
Reason About Locking
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    24
====================
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    25
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    26
We should spend some time thinking hard about locking, especially on
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    27
.git/index etc. We're probably adequately locking the _git_
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    28
repository, but may not have enough locking correctness in places
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    29
where hg does locking that git isn't aware of (notably the working
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    30
copy, which I believe Git does not lock.)
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    31
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    32
Clean up requirements
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    33
=====================
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    34
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    35
Right now (for historical reasons, mainly) hgext.git uses a
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    36
.hg/this-is-git file to detect repositories that should be treated as
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    37
git. We should look in the .hg/requires for the "git" requirement
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    38
instead (we already set this requirement, so it's mostly keying off
ad718271a9eb git: skeleton of a new extension to _directly_ operate on git repos
Augie Fackler <augie@google.com>
parents:
diff changeset
    39
that instead of using an empty file.)