Use sysconfcpus to simulate CPU count on Travis, for use with Elm

install-sysconfcpus-elm.sh

#!/usr/bin/env bash

# https://github.com/elm-lang/elm-compiler/issues/1473#issuecomment-245704142
#
# Put these lines in your .travis.yml
#
#     install:
#       - source <(curl -sSL https://gist.githubusercontent.com/hkgumbs/a434d214628147955f73ff7a7ce4c22c/raw)
#       - npm install -g elm elm-test elm-format  # etc
#
# Then use `elm2` instead of `elm` (or `elm2 test`, etc)

if [ ! -d sysconfcpus/bin ]
then
  git clone https://github.com/obmarg/libsysconfcpus.git
  pushd libsysconfcpus
  ./configure --prefix=$TRAVIS_BUILD_DIR/sysconfcpus
  make
  make install
  popd
fi

elm2() {
  $TRAVIS_BUILD_DIR/sysconfcpus/bin/sysconfcpus -n 2 elm "$@"
}

export -f elm2