Working with time on Virtual TestNets

For certain types of tests it’s useful to skip through time. This is possible by relying on 2 Admin RPC methods available on Virtual TestNets: evm_setNextBlockTimestamp and evm_setNextBlockTimestamp.

Getting the correct time

During execution of a transaction or eth_call accesses block.timestamp within a contract, the value will depend on whether the target block (latest or pending) block:

• For pending block: block.timestamp == time.now() + adjustment_offset. This represents the current time adjusted by the time-adjustment methods.
• For latest block: block.timestamp == latest_block.timestamp. This is the timestamp of the most recently mined block.

The adjustment_offset comes from time-adjustment methods:

1. evm_setNextBlockTimestamp: Skips time to the timestamp for the next block: adjustment_offset = timestamp - time.now().

2. evm_increaseTime: Advances time by a relative amount. adjustment_offset += increase_value

Examples

Increase time by an offset

VIRTUAL_TESTNET_RPC=https://YOUR-RPC-URL-HERE
curl -s -X POST \
  -H "Content-Type: application/json" \
  --data '{
    "jsonrpc": "2.0",
    "method": "evm_increaseTime",
    "params": ["0xe10"],
    "id": 2
  }' "$VIRTUAL_TESTNET_RPC"

Set timestamp for pending block

VIRTUAL_TESTNET_RPC=https://YOUR-RPC-URL-HERE
 
# Get the current date in Unix timestamp format
current_date=$(date +%s)
 
# Use evm_setTime to set the block time to today (current timestamp)
curl -s -X POST \
  -H "Content-Type: application/json" \
  --data '{
    "jsonrpc": "2.0",
    "method": "evm_setNextBlockTimestamp",
    "params": ["'"$current_date"'"],
    "id": 3
  }' "$VIRTUAL_TESTNET_RPC"