lib/index.js
function checkNpmVersion() {
  return execa.shell('npm -v')
    .then(({ stdout }) => stdout)
    .then((v) => {
      if (v && !(v.indexOf('3') === 0)) {
        log('Use npm v3.10.10 for unobtrusive symlinks: npm i -g npm@3.10.10');
      }
    });
}
function checkNpmVersion() {
  return execa.shell('npm -v')
    .then(({ stdout }) => stdout)
    .then((v) => {
      if (v && !(v.indexOf('3') === 0)) {
        log('Use npm v3.10.10 for unobtrusive symlinks: npm i -g npm@3.10.10');
      }
    });
}
function checkNpmVersion ( ) { return execa . shell ( 'npm -v' ) . then ( ( { stdout } ) => stdout ) . then ( ( v ) => { if ( v && ! ( v . indexOf ( '3' ) === 0 ) ) { log ( 'Use npm v3.10.10 for unobtrusive symlinks: npm i -g npm@3.10.10' ) ; } } ) ; }
check npm version and show warning if needed
check npm version and show warning if needed