I’ve had some issues with 4gate pushes in my time, but I’ve come up with a decent solution that was working before the patch, and is now even more effective since the patch.
Check out the video:
The majority of the strategy is to match his gateways with a barracks, and go heavy on marauders. In the case, I went with 4 barracks to directly counter his 4 warpgates. I began to transition into ghosts for the EMP bonus, but also an easy way to deal with immortals and sentries if he decides to bring more of them. It also helps negate large amounts of zealots, between the damage that ghosts do to light(20), EMP, snipe and concussive shell from the Marauders, it makes the Zealots easy enough to deal with, provided they do not have charge.