Extracted from https://github.com/facebook/react/issues/12643.

We're currently diff a host node in the complete phase even if it has bailed out in the begin phase. By itself, this just means we're doing a little bit more work than necessary. But it also has some observable effects. In particular, https://github.com/facebook/react/issues/13424 (which by itself would be very rare and probably not worth fixing) is made worse because we end up committing update to inputs from another component.

I have a fix for this in https://github.com/facebook/react/pull/13423. Filing this for posterity.
)}
        </div>,
        container,
      );
      expect(portal.tagName).toBe('DIV');
      portal.click();
      expect(ops).toEqual(['portal clicked', 'parent clicked']);
    } finally {
      document.body.removeChild(portalContainer);
    }
  });
  it('should not onMouseLeave when staying in the portal', () => {
    const portalContainer = document.createElement('div');
    document.body.appendChild(container);
    document.body.appendChild(portalContainer);
    let ops = [];
    let firstTarget = null;
    let secondTarget = null;
    let thirdTarget = null;
    function simulateMouseMove(from, to) {
      if (from) {
        from.dispatchEvent(
          new MouseEvent('mouseout', {
            bubbles: true,
            cancelable: true,
            relatedTarget: to,
          }),
        );
      }
      if (to) {