Raffle fulfilRandomWords unit test: why is the winner always at index 2???

[techybolek]

in Raffle.test.js the winner picked handler reads:

...

 try {
                              // Now lets get the ending values...
                              const recentWinner = await raffle.getRecentWinner()
                              const raffleState = await raffle.getRaffleState()
                              const winnerBalance = await accounts[2].getBalance()

Why is the winner supposed to be at index 2? And how come the test passes with the winner hardcoded to index 2?

[alymurtazamemon]

@techybolek It is the mock of the actual implementation, it will always returns the same first account as winner.