Git: Conversion of a Subdirectory to a Submodule

I have successfully been able to convert Submodules to Subdirectories using commands such as the methods outlined in these two examples:

Submodule->Subdir

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  • Subdir->Submodule

    The challenge is to successfully achieve this on a directory, preserving its history through each conversion.
    These two methods outlined above have worked fine on a trivial experimental repository, but does not handle a more complex repository. e.g, a repo with an arbitrary commit pattern.

    The problem exposes itself when executing

    git filter-branch --subdirectory-filter <lib-directory> -- --all

    when trying to convert a directory (that was previously a submodule) to a submodule. If I understand correctly. This was throwing:

    Rewrite c95281d27e4602e9af50146eefcf7c28f5bb4f35 
            (2/11)a989b207d3757f9803fd50fa2d77908a4dc1330e
    fatal: failed to unpack tree object 
           c95281d27e4602e9af50146eefcf7c28f5bb4f35:lib/test_submodule
    Could not initialize the index`
    

    of which there were absolutely no similar results online.
    It was figured this was occurring due to the recurring reference to the submodule within the INDEX, whereby when the submodule was converted, the above error would occur.

    Is there some way of performing a filter-branch that will allow the avoidance of these earlier references to the submodule??

    Edit: I’ve come back looking at this issue again, and I still haven’t found a way to solve it. Using the Subdir->Submodule method with git filter-branch works fine for a normal directory; but crashes when it hits a submodule.
    The crash that keeps happening at this section within git:

    https://github.com/github/git-msysgit/blob/master/git-filter-branch.sh#L300

    I can’t make much sense of it though.

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  • 2 Solutions collect form web for “Git: Conversion of a Subdirectory to a Submodule”

    For me it worked after adding a trailing slash to the directory:

    $ git filter-branch --subdirectory-filter htdocs/typo3_src -- --all
    Rewrite cbe03e13da071403a2632263f1760b560398cdd3 (1/12) (0 seconds passed, remaining 0 predicted)    004b20fc15023539484c7f5990b99780f54dc0ac
    fatal: failed to unpack tree object cbe03e13da071403a2632263f1760b560398cdd3:htdocs/typo3_src
    Could not initialize the index
    
    $ git filter-branch --subdirectory-filter htdocs/typo3_src/ -- --all
    Rewrite ec6e3c7212f1080fc052c87b1129335ab5bee524 (5/10) (1 seconds passed, remaining 1 predicted)    
    Ref 'refs/heads/master' was rewritten
    Ref 'refs/remotes/origin/master' was rewritten
    Ref 'refs/remotes/origin/develop' was rewritten
    WARNING: Ref 'refs/remotes/origin/master' is unchanged
    WARNING: Ref 'refs/tags/0.0.1' is unchanged
    

    Instead of using the rev-list option –all, try filtering by commit hash instead.

    git filter-branch --subdirectory-filter <lib-directory> <hash>...
    

    The commit that caused the problem in my case was the one containing the Subproject commit. Example:

    git filter-branch --subdirectory-filter <lib-directory> c95281d27e4...
    
    Git Baby is a git and github fan, let's start git clone.