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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);

SEE ALSO