cycling between two hashes leads to incorrect location stack

[hedgepigdaniel]

const  action1 = {
  type: 'HOME',
  hash: 's1',
}
const action2 = {
  type: 'HOME',
  hash: 's2',
}

If you render links corresponding to these actions and then click on them in the following order:

dispatch(action1);
dispatch(action2);
dispatch(action1);

Then the kind of the 3rd action when it hits the reducers is back rather than push, and the browser stack has 2 entries instead of three.

[hedgepigdaniel]

Cycling between three actions is fine - the bug only occurs when transitioning to the previous hash.

[hedgepigdaniel]

Reproduceable on the repro/scroll branch. Try using the section links in the sidebar. A pattern of 0-1-4-0-1-4 etc works fine, but a pattern like 0-1-0-1 etc does not.