@gridsome/cli/lib/utils/index.js

A command line tool for creating new Gridsome projects.

const execa = require('execa')
const semver = require('semver')

exports.hasYarn = async function () {
  try {
    const { stdout: version } = await execa('yarn', ['--version'])
    return semver.satisfies(version, '>= 1.4.0')
  } catch (err) {}
  return false
}

exports.isGridsomeProject = function (pkgPath) {
  const projectPkgJson = pkgPath ? require(pkgPath) : {}
  const { devDependencies = {}, dependencies = {}} = projectPkgJson
  const packages = { ...devDependencies, ...dependencies }

  return packages.hasOwnProperty('gridsome')
}