stop() and onStop()

When the stop(runner) function is invoked, it will remove the effect associated with the runner from the dependencies.

The onStop function is the callback function of stop function.

Optimizing stop

We that changing obj.foo = 3 to obj.foo++ in the previous stop unit test causes the test to fail.

Why does this happen?

Firstly, let's distinguish between obj.foo++ and obj.foo = 3:

The former is equivalent to obj.foo = obj.foo + 1.

which involves two get operations and one set operation.

Whereas the latter involves only one set operation.

When a get operation is triggered, the dependencies will be re-collected, and that's why the unit test failed.