script.runInContext()

script.runInContext(contextifiedSandbox[, options])

Similar to vm.runInContext() but a method of a precompiled Script object. script.runInContext() runs script's compiled code in contextifiedSandbox and returns the result. Running code does not have access to local scope.

script.runInContext() takes the same options as script.runInThisContext().

Example: compile code that increments a global variable and sets one, then execute the code multiple times. These globals are contained in the sandbox.

const util = require('util');
const vm = require('vm');

var sandbox = {
  animal: 'cat',
  count: 2
};

var context = new vm.createContext(sandbox);
var script = new vm.Script('count += 1; name = "kitty"');

for (var i = 0; i < 10; ++i) {
  script.runInContext(context);
}

console.log(util.inspect(sandbox));

// { animal: 'cat', count: 12, name: 'kitty' }

Note that running untrusted code is a tricky business requiring great care. script.runInContext() is quite useful, but safely running untrusted code requires a separate process.