Martin Waitz <tali@xxxxxxxxxxxxxx> writes: > On Mon, May 21, 2007 at 06:59:38PM +0200, Jan Hudec wrote: >> Here is one possible idea: >> >> We could store the GIT_DIR of submodule within the GIT_DIR of the >> superproject instead of the submodule directory itself. So instead of: >> / >> /.git >> /subdir >> /subdir/.git >> >> There would be: >> / >> /.git >> /subdir >> /.git/submodules/submodule-name.git >> >> This would require changes to the logic how git finds GIT_DIR (which would be >> really deep change), but it would provide place to store the submodule data >> while the submodule is not being checked out. > > I agree that we need something like that. > > We don't have to move the entire subproject.git into the superproject, > but we need to have all _referenced_ objects in the .git dir of the > superproject. > > There are several possibilities to do so: > > * move the entire .git dir > * move .git/objects > * explicitly copy all referenced objects I was hoping that we can start from an initial cut that supports only a superproject that had its subprojects in their places from its initial commit, and did not have to worry about this from day one, and deal with this kind of "more advanced" stuff incrementally. Unfortunately it's more fun to talk about more advanced stuff than starting with small but solid stuff. And we would need to make sure whatever we do as the "small but solid" initial round can later support more advanced arrangements later, so we would need to think about the issues now anyway to a certain degree. How about doing something like this, instead? (1) superproject .gitmodules (in-tree) and .git/config (local repository) use the three-level naming in $gmane/47567. Namely, (1a) .gitmodules says which subdirectory has a checkout of what project, and names the project in logical/abstract terms, not with a URL (e.g. "kernel26"); (1b) .gitmodules also associates a set of suggested URLs for each of the logical/abstract project name; (1c) .git/config records which project are of interest. (2) In superproject .git/, we would have a bare repository for each project used by the superproject. .git/subproject/kernel26/{objects,refs,...} This is created by making a bare clone from the upstream URL, decided by the user with the help from suggested URL described in the superproject .gitmodules. The idea is to use this repository as a long-term subproject state across branch switching. (3) When we need to check out a revision of superproject whose .gitmodules has "kernel-src/ -> kernel26", and when we haven't done so (perhaps we are doing an initial checkout, perhaps we are switching from a different revision of the superproject that did not have "kernel26" project at kernel-src/ directory), we rm -f kernel-src/ and then "git-clone -l -s" from the repository we keep in (2) to populate kernel-src/ directory. (4) Before performing the above step (3), we need to make sure we are not losing anything in kernel-src/ if exists. Three cases plus one: (4a) The path kernel-src/ in the old checkout was not a subproject (either it did not exist, it was a blob, or it was a directory with files that are tracked as part of the superproject). The usual "don't lose local modification" rule we use try to carry local changes forward across branch switching, but in this case we shouldn't do so. (4b) It has the same logical/abstract project checked out; the commit recorded in the superproject tree may or may not be the same as what its HEAD points at. In this case we do not have to worry about swapping the git repository at kernel-src/ directory, although we would need to check out the correct revision, and worry about what to do with any local modification (I think the usual "don't lose local modification but carry them forward" rule would be Ok in this case). (4c) It has a different project checked out; we need to be careful to keep local changes, and also we need to make sure the local changes in this subproject repository are pushed back to (2). It could be that automated "git push" after making sure everything is committed is sufficient and have the user handle failure cases. (4d) This applies not just "before step (3)", but in cases where we need to replace a checked out subproject directory with something else (e.g. blob or directory that belong to the superproject, or noneness). We would need to make sure no local change is lost, and the repository is synched up with (2). I think an arrangement like this would solve "symlink is a bitch for MinGW" problem Johannes Sixt brought up today with Sven's RFC as well. - To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html