Run FlowCal (macOS)

#!/bin/sh

# Run FlowCal using Python. The Python version should be the one installed by
# Anaconda. As with the `Install FlowCal (macOS)` script, look up the current
# default shell, run it as an interactive login shell with a clean
# environment, and use it to run the FlowCal Excel UI.

# Look up default shell for current user using the directory service command
# line utility (dscl).
default_shell="$(dscl . -read Users/$(whoami) UserShell \
                 | sed 's/UserShell: //')"

# Commands that run FlowCal. (Commands are collected via a here document,
# which is input to a `tr` command that removes the newline characters.) The
# export command changes the default matplotlib backend, which is necessary
# to properly show the open file dialog.
run_flowcal="$(tr -d '\012' <<END
export MPLBACKEND='TkAgg';
python -m FlowCal.excel_ui -v -p -H;
END
)"

# Run commands in the default shell run as an interactive ("-i") login ("-l")
# shell with a clean environment ("env -i", so the PATH variable is not
# inherited from this shell and mangled). (Getting zsh to source .zshrc
# requires an interactive shell; getting bash to source .bash_profile
# requires a login shell.)
env -i $default_shell -i -l -c "${run_flowcal}"