Can timecop be used to override the native functions for all requests?

[WillGibson]

We have some Behat scenarios which revolve around what happens just before and just after midday.

So we need to specify the time in a step, then make a request to a URL to see what happens.

I thought timecop might cover this, but it seems to only affect the process where you call timecop_freeze().

Am I missing something, or do I need to look for another approach.

[IonBazan]

You should save the specified time in filesystem or other storage. Then load this time in the second request and freeze the time using timecop.
Better solution would be to use a time provider to mock the time in a more elegant way.