Backport notice:
- data have real blocks from testnet
- due to big gap in blocks before checkpoints (half-year) for sack of this test is added one more checkpoint, otherwise blocks are not accepted due to non-mockable time for other chains except regtest
- data for 2 blocks in split chain are generated locally for testnet
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333317ce6b67aa92f7363d48cd750712190b4b6b test: Test that low difficulty chain fork is rejected (MarcoFalke)
fa31dc1bf4ee471c4641eef8de02702ba0619ae7 test: Pass down correct chain name in tests (MarcoFalke)
Pull request description:
To prevent OOM, Bitcoin Core will reject chain forks at low difficulty by default. This is the only use-case of checkpoints, so add a test for it to make sure the feature works as expected. If it didn't work, checkpoints would have no use-case and we might as well remove them
ACKs for top commit:
Sjors:
Thanks for adding the node 1 example. Code review ACK 333317c
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