Regular expression for matching a shebang line
$ npm install shebang-regex
const shebangRegex = require('shebang-regex');
const string = '#!/usr/bin/env node\nconsole.log("unicorns");';
shebangRegex.test(string);
//=> true
shebangRegex.exec(string)[0];
//=> '#!/usr/bin/env node'
shebangRegex.exec(string)[1];
//=> '/usr/bin/env node'MIT © Sindre Sorhus