A sample files of Heroku CI

app.json

{
  "environments": {
    "test": {
      "scripts": {
        "test-setup": "./script/test-setup",
        "test": "./script/test"
      }
    }
  }
}

test

#!/bin/sh -eux

./hadolint Dockerfile*
./shellcheck script/*

test-setup

#!/bin/sh -eux

## hadolint

HADOLINT_VERSION=v1.15.0

curl -sLo hadolint https://github.com/hadolint/hadolint/releases/download/${HADOLINT_VERSION}/hadolint-Linux-x86_64
chmod 500 hadolint
./hadolint -v

## shellcheck

curl -s https://storage.googleapis.com/shellcheck/shellcheck-stable.linux.x86_64.tar.xz | \
  tar xvJf - --strip-components=1 shellcheck-stable/shellcheck
./shellcheck -V