[MacPorts] #50708: Base should support fetching git submodules (git submodule update)

[MacPorts]

#50708: Base should support fetching git submodules (git submodule update)
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  Reporter:  mojca@…  |      Owner:  macports-tickets@…
      Type:  defect   |     Status:  new
  Priority:  Normal   |  Milestone:
 Component:  base     |    Version:  2.3.4
Resolution:           |   Keywords:
      Port:           |
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Comment (by rjvbertin@…):

 The problem I've faced at several occasions is that a simple checkout of a
 known commit followed by the standard submodule fetch left me with a
 mismatch between the main and the sub modules. So what I do now is a `git
 clone --recursive` followed by a `git checkout -q ${git.branch}` in the
 working copy. That takes care of the main source tree. In order to get the
 known & tested submodule version I need to do some extra work in the post-
 fetch. If we ignore the reinplace in the .git/config file which is there
 for other reasons, I do `git submodule update --init ; git submodule
 update` in the toplevel working copy followed by a series of git commands
 in the submodule working copy that leave me with the known commit. It
 might be possible to do that in less than the 3 commands I'm using, but if
 so I haven't yet found out how.

 Part of this complexity may stem from the fact that I've been trying to
 support the use of a local working copy as the git, something I clearly
 dropped when it became impossible. I probably ought to revisit the
 submodule post-fetch code to see if it cannot be simplified, but that's
 got a bit too much of a fixing something that ain't broke thing (and the
 repo is big so takes a bit too much time to check out repeatedly).

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Ticket URL: <https://trac.macports.org/ticket/50708#comment:9>
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