A shell function to run a docker command to check if package.json contains a specific script name

package_has_script.sh

package_has_script () {
    script_name="${1}"

    # Check if package.json contains a script of the given name
    docker run \
        --volume `pwd`:`pwd` --workdir `pwd`  `# Use the current directory`  \
        --entrypoint node                     `# Run plain old node`  \
        canonicalwebteam/yarn:v0.2.0          `# Run a short inline node script to check the package.json`  \
            --eval "
                process.exit(
                    ! JSON.parse(
                        fs.readFileSync('package.json', 'utf8')
                    ).scripts.hasOwnProperty('${script_name}')
                )
            "
}