Sinon - ensure object does not have property

There isn't currently a built-in matcher for that.

Sinon allows you to create custom matchers so you could create your own, here is one for doesNotHave based on the built-in has matcher:

import * as sinon from 'sinon';

const doesNotHave = (prop) => sinon.match(function (actual) {
  if(typeof value === "object") {
    return !(prop in actual);
  }
  return actual[prop] === undefined;
}, "doesNotHave");

test('properties', () => {
  const obj = { foo: 'bar' };
  sinon.assert.match(obj, sinon.match.has('foo'));  // SUCCESS
  sinon.assert.match(obj, doesNotHave('baz'));  // SUCCESS
})

I've just realized that it's possible to specify undefined in the object's shape to make the check:

sinon.assert.match(actual, {
  shouldNotExists: undefined
});

Not completely sure if it's 100% valid, but seems to do the job.

You cannot use sinon for this, you have to use something like chai.

You would do:

cont { expect } = require("chai");

expect({ foo: true }).to.not.have.keys(['bar']);

https://runkit.com/embed/w9qwrw2ltmpz