Re: [PATCH] allow setting GIT_WORK_TREE to "no work tree"

> Johannes Schindelin schrieb:
> 
> > On Wed, 6 Feb 2008, Johannes Sixt wrote:
> > 
> >> Jeff King schrieb:
> >>> In setup_git_directory_gently, we have a special rule that says "if 
> >>> GIT_DIR is set but GIT_WORK_TREE is not, then use the current 
> >>> working directory as the work tree." This is the intended behavior 
> >>> for the user perspective.
> >>>
> >>> However, setup_git_directory_gently sets GIT_DIR itself, meaning 
> >>> that further setups (either because we are executing a command via 
> >>> alias, or in a subprocess) will see the non-existent GIT_WORK_TREE 
> >>> and assume we fall into the "current working directory is the 
> >>> working tree" codepath.
> >>>
> >>> Instead, we now use a special value of GIT_WORK_TREE to indicate 
> >>> that we have already checked for a worktree and that there isn't 
> >>> one, setting it when we set GIT_DIR and checking for it in the 
> >>> special case path.
> >>>
> >>> The special value is a blank GIT_WORK_TREE; it could be any value, 
> >>> but this should not conflict with any user values (and as a bonus, 
> >>> you can now tell git "I don't have a work tree" with "GIT_WORK_TREE= 
> >>> git", though I suspect the use case for that is limited).
> >>
> >> Hrm. Unfortunately, on Windows there is no such thing as an empty 
> >> environment string. setenv(x, "") *removes* the environment variable.
> > 
> > That might be a shortcoming of our implementation of setenv():
> 
> No, it is not. It's Windows's putenv(), and it's even documented.