It will only take a few seconds to mine all these blocks, which
certainly makes it easy for testing. If you check your wallet balance,
you will see that you earned reward for the first 400 blocks (coinbase
rewards must be 100 blocks deep before you can spend them):
rewards must be 100 blocks deep before you can ((("blockchain", "test blockchains", "regtest", startref="blockchain-test-regtest")))((("test blockchains", "regtest", startref="test-block-regtest")))((("regtest", startref="regtest")))spend them):