Version: 15.0.1

Assuming a class instance like so

class Thing {
  aMethod() {}
}
const thing = new Thing();

and a spy like so

sinon.spy(thing, 'aMethod');

a global restore will error

sinon.restore();

This is because sinon attempts to directly set target[property] back to the original method, which is caught by the spy proxy.

Example Error:

TypeError: Cannot assign to read only property 'setRequestReviewers' of object '[object Object]'
         at Function.restore