Describe the bug

When opening a new terminal window in a directory with a Pipfile, a sub shell is not activated in the same way as if I cd into that directory.

To Reproduce

1. cd /some/dir/with/pipenv. Note that pipenv shell is activated.
2. Open a new terminal window in that same directory. Note that pipenv shell is not activated.
3. cd ../pipenv. Note that the shell is now activated.

Expected behavior

The shell should be activated when a new terminal window is opened.

Desktop

• OS / Distro: macOS 10.15.5 (19F101)
• Latest ohmyzsh update?: Yes
• ZSH Version: zsh 5.7.1 (x86_64-apple-darwin19.0)
• Terminal emulator: Apple Terminal.app