// Stubs don't do any magical modifications to your namespace. They // just provide you a function that records what arguments get passed // to it. To use stubs as something more like "spies," use something // like set_global() to override your namespace. exports.make_stub = function () { const self = {}; self.num_calls = 0; self.f = function (...args) { self.last_call_args = args; self.num_calls += 1; return true; }; self.get_args = function (...param_names) { const result = {}; for (const [i, name] of param_names.entries()) { result[name] = self.last_call_args[i]; } return result; }; return self; }; exports.with_stub = function (f) { const stub = exports.make_stub(); f(stub); assert.equal(stub.num_calls, 1); }; (function test_ourselves() { exports.with_stub(function (stub) { stub.f('blue', 42); const args = stub.get_args('color', 'n'); assert.equal(args.color, 'blue'); assert.equal(args.n, 42); }); }());