What: git-new-workdir [1] with submodule support.

Why: you want to have multiple full trees (checkouts) of your repository, so that if you have a full build of a certain branch in checkout1, you don't have to do any rebuilding when you switch back and forth to another branch in checkout2.

There is logically only one local repository, and just many checkouts of it, so it's very easy to share patches between various checkouts and your branches are all in one centralized place.

How: it uses git-new-workdir under the hood. In addition to calling git-new-workdir for the parent repository, it also recursively calls git-new-workdir for all its (initialised and updated) submodules.

Usage:

• Make sure git-new-workdir is on your path
• Run ./git-new-workdir-recursive <repository> <new_workdir> [<branch>]

Example usage:

ghc-pristine is an ordinary Git clone of the main GHC repository, the one that you've been working on sofar. It has a master branch (currently checked out) and a some-bugfix branch.

Create a new working directory to validate some-bugfix.

$ git-new-workdir-recursive ghc-pristine ghc-validate-some-bugfix some-bugfix
Creating 'ghc-validate-some-bugfix' <- 'ghc-pristine'
Previous HEAD position was 4c9620f... TrieMap: Minor documentation fix
Switched to branch 'some-bugfix'
Creating 'ghc-validate-some-bugfix/.arc-linters/arcanist-external-json-linter' <- 'ghc-pristine/.arc-linters/arcanist-external-json-linter'
Creating 'ghc-validate-some-bugfix/libffi-tarballs' <- 'ghc-pristine/libffi-tarballs'
Creating 'ghc-validate-some-bugfix/libraries/Cabal' <- 'ghc-pristine/libraries/Cabal'
Creating 'ghc-validate-some-bugfix/libraries/Win32' <- 'ghc-pristine/libraries/Win32'
Creating 'ghc-validate-some-bugfix/libraries/array' <- 'ghc-pristine/libraries/array'
Creating 'ghc-validate-some-bugfix/libraries/binary' <- 'ghc-pristine/libraries/binary'
Creating 'ghc-validate-some-bugfix/libraries/bytestring' <- 'ghc-pristine/libraries/bytestring'
Creating 'ghc-validate-some-bugfix/libraries/containers' <- 'ghc-pristine/libraries/containers'
Creating 'ghc-validate-some-bugfix/libraries/deepseq' <- 'ghc-pristine/libraries/deepseq'
Creating 'ghc-validate-some-bugfix/libraries/directory' <- 'ghc-pristine/libraries/directory'
Creating 'ghc-validate-some-bugfix/libraries/filepath' <- 'ghc-pristine/libraries/filepath'
Creating 'ghc-validate-some-bugfix/libraries/haskeline' <- 'ghc-pristine/libraries/haskeline'
Creating 'ghc-validate-some-bugfix/libraries/hoopl' <- 'ghc-pristine/libraries/hoopl'
Creating 'ghc-validate-some-bugfix/libraries/hpc' <- 'ghc-pristine/libraries/hpc'
Creating 'ghc-validate-some-bugfix/libraries/parallel' <- 'ghc-pristine/libraries/parallel'
Creating 'ghc-validate-some-bugfix/libraries/pretty' <- 'ghc-pristine/libraries/pretty'
Creating 'ghc-validate-some-bugfix/libraries/primitive' <- 'ghc-pristine/libraries/primitive'
Creating 'ghc-validate-some-bugfix/libraries/process' <- 'ghc-pristine/libraries/process'
Creating 'ghc-validate-some-bugfix/libraries/random' <- 'ghc-pristine/libraries/random'
Creating 'ghc-validate-some-bugfix/libraries/stm' <- 'ghc-pristine/libraries/stm'
Creating 'ghc-validate-some-bugfix/libraries/terminfo' <- 'ghc-pristine/libraries/terminfo'
Creating 'ghc-validate-some-bugfix/libraries/time' <- 'ghc-pristine/libraries/time'
Creating 'ghc-validate-some-bugfix/libraries/transformers' <- 'ghc-pristine/libraries/transformers'
Creating 'ghc-validate-some-bugfix/libraries/unix' <- 'ghc-pristine/libraries/unix'
Creating 'ghc-validate-some-bugfix/libraries/vector' <- 'ghc-pristine/libraries/vector'
Creating 'ghc-validate-some-bugfix/libraries/xhtml' <- 'ghc-pristine/libraries/xhtml'
Creating 'ghc-validate-some-bugfix/nofib' <- 'ghc-pristine/nofib'
Creating 'ghc-validate-some-bugfix/utils/haddock' <- 'ghc-pristine/utils/haddock'
Creating 'ghc-validate-some-bugfix/utils/hsc2hs' <- 'ghc-pristine/utils/hsc2hs'

$ cd ghc-validate-some-bugfix && ./validate

Caveat: Make sure you don't checkout the same branch from different working directories. It will confuse git if you commit to that branch from one working directory, as the other working directory will now be out date.

I usually name my working directories after the branch that they have checked out.

Bugs:

• git-new-workdir-recursive unsets core.worktree for each submodule in the original repo. Certain scripts (e.g. vim-fugitive) will become unusable in the submodules of the original repository, but work fine in the new work directories.

Author: Thomas Miedema Homepage: https://github.com/thomie/git-new-workdir-recursive

[1] https://github.com/git/git/blob/master/contrib/workdir/git-new-workdir