git pull and GIT_DIR

It appeared that

a) cd /path/to && git pull git/https://....

will fetch and checkout latest changes to working tree. This is as expected. On the contrary

b) GIT_DIR=/path/to/.git git pull git/https://....

will only update git repo, but leaving working tree untouched. Subsequent git status and git diff will indicate unstaged changes, apparently a commit that will revert the updated git repo. I have to do 'git reset --hard' to really update the working three.

I'm not sure if this is an intended behavior or I missed something. 

bill lam <cbill.lam@gmail.com> writes:

-ETOOLITTLEINFO.

When you do b)

 - is /path/to the working tree for /path/to/.git?

 - where is your $(pwd)?

 - if your $(pwd) is different from /path/to, how are you telling git
   where the working tree is?  are you using GIT_WORK_TREE or something?

It is non-bare and /path/to is the working tree. The git pull was run inside a shell and $(pwd) is $HOME. GIT_WORK_TREE is not used. This let me remember that there were some directories/files checkout under $HOME that should be under /path/to. I might recall incorrectly, but does it mean that it need to use the form

GIT_DIR=/path/to/.git GIT_WORK_TREE=/path/to git pull url

to make it to the samething as

cd /path/to && git pull url