• Jens Lehmann's avatar
    fetch/pull: recurse into submodules when necessary · 88a21979
    Jens Lehmann authored
    To be able to access all commits of populated submodules referenced by the
    superproject it is sufficient to only then let "git fetch" recurse into a
    submodule when the new commits fetched in the superproject record new
    commits for it. Having these commits present is extremely useful when
    using the "--submodule" option to "git diff" (which is what "git gui" and
    "gitk" do since 1.6.6), as all submodule commits needed for creating a
    descriptive output can be accessed. Also merging submodule commits (added
    in 1.7.3) depends on the submodule commits in question being present to
    work. Last but not least this enables disconnected operation when using
    submodules, as all commits necessary for a successful "git submodule
    update -N" will have been fetched automatically. So we choose this mode as
    the default for fetch and pull.
    
    Before a new or changed ref from upstream is updated in update_local_ref()
    "git rev-list <new-sha1> --not --branches --remotes" is used to determine
    all newly fetched commits. These are then walked and diffed against their
    parent(s) to see if a submodule has been changed. If that is the case, its
    path is stored to be fetched after the superproject fetch is completed.
    
    Using the "--recurse-submodules" or the "--no-recurse-submodules" option
    disables the examination of the fetched refs because the result will be
    ignored anyway.
    
    There is currently no infrastructure for storing deleted and new
    submodules in the .git directory of the superproject. That's why fetch and
    pull for now only fetch submodules that are already checked out and are
    not renamed.
    
    In t7403 the "--no-recurse-submodules" argument had to be added to "git
    pull" to avoid failure because of the moved upstream submodule repo.
    
    Thanks-to: Jonathan Nieder <[email protected]>
    Thanks-to: Heiko Voigt <[email protected]>
    Signed-off-by: default avatarJens Lehmann <[email protected]>
    Signed-off-by: default avatarJunio C Hamano <[email protected]>
    88a21979
t7403-submodule-sync.sh 1.63 KB