'use strict'; require('../common'); const assert = require('assert'); const spawn = require('child_process').spawn; const args = ['-i']; const child = spawn(process.execPath, args); const input = '(function(){"use strict"; const y=1;y=2})()\n'; const expectOut = /^> TypeError: Assignment to constant variable.\n/; child.stderr.setEncoding('utf8'); child.stderr.on('data', function(c) { throw new Error('child.stderr be silent'); }); child.stdout.setEncoding('utf8'); let out = ''; child.stdout.on('data', function(c) { out += c; }); child.stdout.on('end', function() { assert(expectOut.test(out)); console.log('ok'); }); child.stdin.end(input);