activeFork
Signature
function activeFork() external returns (uint256);
Description
Returns the identifier for the currently active fork. Reverts if no fork is currently active.
Examples
Get the currently active fork id:
uint256 mainnetForkId = vm.createFork(MAINNET_RPC_URL);
uint256 optimismForkId = vm.createFork(OPTIMISM_RPC_URL);
assert(mainnetForkId != optimismForkId);
vm.selectFork(mainnetForkId);
assertEq(vm.activeFork(), mainnetForkId);
vm.selectFork(optimismForkId);
assertEq(vm.activeFork(), optimismForkId);