#!/bin/sh -e

err() { echo 1>&2 "$@"; exit 1; }

[ -n "$1" -a -z "$2" ]          || err 'Usage: cover <filename>'
[ -r "$1" ]                     || err "Cannot read $1."
coverage erase           || err 'Cannot run coverage.'
coverage run "$1"
rm -rf htmlcov
coverage html
xdg-open htmlcov/