Why doesn't setting GIT_WORK_TREE work in a post-commit hook?

Question

I\'m trying to use the following post-commit hook to deploy to a particular directory after each successful commit:

#!/bin/sh
export GIT_WORK_TR         


        

Answer 1

The problem here is that in post-commit hooks (and also pre-commit, prepare-commit-msg and commit-msgt) the GIT_INDEX_FILE environment variable is set to .git/index. (This isn't documented in the githooks documentation, but I've posted elsewhere about the settings of environment variables and the current directory in git hooks.)

The effect of the GIT_INDEX_FILE environment variable is described in the ENVIRONMENT VARIABLES section of the git man page as:

GIT_INDEX_FILE

This environment [variable] allows the specification of an alternate index file. If not specified, the default of $GIT_DIR/index is used.

... and for some reason, in this situation, GIT_INDEX_FILE is being used relative to GIT_WORK_TREE.

To make the hook work as you would expect, you just need to unset GIT_INDEX_FILE, so your hook would look like:

 #!/bin/sh
 unset GIT_INDEX_FILE
 export GIT_WORK_TREE=/var/www/example/
 export GIT_DIR=/home/mark/test/.git/
 git checkout -f