example.js

const sinon = require('sinon')

class TestObject {
    someFunction() {
        console.error('sinon should stub me!');
    }
}

const sandbox = sinon.sandbox.create();

const instance = new TestObject();
const stub = sandbox.stub(instance, 'someFunction'); // This fails on Sinon 3.0, it worked on Sinon 2.x

example_output.log

accalia_de_elementia:~/workspace/sinon_issue_repro $ npm install sinon
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN chat-example@0.0.0 No repository field.
npm WARN chat-example@0.0.0 No license field.

+ sinon@3.0.0
added 13 packages in 6.57s
accalia_de_elementia:~/workspace/sinon_issue_repro $ node example.js 
/home/ubuntu/workspace/node_modules/sinon/lib/sinon/collection.js:90
            throw new TypeError("Cannot stub non-existent own property " + valueToString(property));
            ^

TypeError: Cannot stub non-existent own property someFunction
    at Object.stub (/home/ubuntu/workspace/node_modules/sinon/lib/sinon/collection.js:90:19)
    at Object.<anonymous> (/home/ubuntu/workspace/sinon/example.js:12:22)
    at Module._compile (module.js:569:30)
    at Object.Module._extensions..js (module.js:580:10)
    at Module.load (module.js:503:32)
    at tryModuleLoad (module.js:466:12)
    at Function.Module._load (module.js:458:3)
    at Function.Module.runMain (module.js:605:10)
    at startup (bootstrap_node.js:158:16)
    at bootstrap_node.js:575:3
accalia_de_elementia:~/workspace/sinon_issue_repro $