package: don't run shellHook in nested nix-shells

If a nested nix-shell is run inside a nix-shell, then the outer shell's
shellHook will be passed through and run again, unless the nested shell
defines its own.

With lix's hook, this can be annoying: forgetting to exit its nix-shell,
cd'ing to another repository & entering a nested nix-shell will happily
install lix's pre-commit hook in it.

This change makes lix's hook return early in such cases.

Change-Id: I91cb6eb6668f3a8eace36ecbdb01eb367861d77b

0 files changed, 0 insertions, 0 deletions