text: #!/usr/bin/env python3
  # Copyright (c) 2014-2016 The Bitcoin Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  """Test the invalidateblock RPC."""
  
  import time
  
  from test_framework.test_framework import BitcoinTestFramework
  from test_framework.util import assert_equal, connect_nodes, wait_until
  
  class InvalidateTest(BitcoinTestFramework):
      def set_test_params(self):
          self.setup_clean_chain = True
          self.num_nodes = 3
  
      def setup_network(self):
          self.setup_nodes()
  
      def run_test(self):
          self.log.info("Make sure we repopulate setBlockIndexCandidates after InvalidateBlock:")
          self.log.info("Mine 4 blocks on Node 0")
          self.nodes[0].generatetoaddress(4, self.nodes[0].get_deterministic_priv_key().address)
          assert self.nodes[0].getblockcount() == 4
          besthash = self.nodes[0].getbestblockhash()
  
          self.log.info("Mine competing 6 blocks on Node 1")
          self.nodes[1].generatetoaddress(6, self.nodes[1].get_deterministic_priv_key().address)
          assert self.nodes[1].getblockcount() == 6
  
          self.log.info("Connect nodes to force a reorg")
          connect_nodes(self.nodes[0], 1)
          self.sync_blocks(self.nodes[0:2])
          assert self.nodes[0].getblockcount() == 6
          badhash = self.nodes[1].getblockhash(2)
  
          self.log.info("Invalidate block 2 on node 0 and verify we reorg to node 0's original chain")
          self.nodes[0].invalidateblock(badhash)
          newheight = self.nodes[0].getblockcount()
          newhash = self.nodes[0].getbestblockhash()
          if (newheight != 4 or newhash != besthash):
              raise AssertionError("Wrong tip for node0, hash %s, height %d"%(newhash,newheight))
  
          self.log.info("Make sure we won't reorg to a lower work chain:")
          connect_nodes(self.nodes[1], 2)
          self.log.info("Sync node 2 to node 1 so both have 6 blocks")
          self.sync_blocks(self.nodes[1:3])
          assert self.nodes[2].getblockcount() == 6
          self.log.info("Invalidate block 5 on node 1 so its tip is now at 4")
          self.nodes[1].invalidateblock(self.nodes[1].getblockhash(5))
          assert self.nodes[1].getblockcount() == 4
          self.log.info("Invalidate block 3 on node 2, so its tip is now 2")
          self.nodes[2].invalidateblock(self.nodes[2].getblockhash(3))
          assert self.nodes[2].getblockcount() == 2
          self.log.info("..and then mine a block")
          self.nodes[2].generatetoaddress(1, self.nodes[2].get_deterministic_priv_key().address)
          self.log.info("Verify all nodes are at the right height")
          time.sleep(5)
          assert_equal(self.nodes[2].getblockcount(), 3)
          assert_equal(self.nodes[0].getblockcount(), 4)
          node1height = self.nodes[1].getblockcount()
          if node1height < 4:
              raise AssertionError("Node 1 reorged to a lower height: %d"%node1height)
  
          self.log.info("Make sure ResetBlockFailureFlags does the job correctly")
          self.restart_node(0, extra_args=["-checkblocks=5"])
          self.restart_node(1, extra_args=["-checkblocks=5"])
          connect_nodes(self.nodes[0], 1)
          self.nodes[0].generate(10)
          self.sync_blocks(self.nodes[0:2])
          newheight = self.nodes[0].getblockcount()
          for j in range(2):
              self.restart_node(0, extra_args=["-checkblocks=5"])
              tip = self.nodes[0].generate(10)[-1]
              self.nodes[1].generate(9)
              connect_nodes(self.nodes[0], 1)
              self.sync_blocks(self.nodes[0:2])
              assert_equal(self.nodes[0].getblockcount(), newheight + 10 * (j + 1))
              assert_equal(self.nodes[1].getblockcount(), newheight + 10 * (j + 1))
              assert_equal(self.nodes[1].getbestblockhash(), tip)
  
          tip = self.nodes[1].getbestblockhash()
          self.nodes[1].invalidateblock(self.nodes[1].getblockhash(newheight + 1))
          self.nodes[1].invalidateblock(self.nodes[1].getblockhash(newheight + 1))
  
          assert_equal(self.nodes[1].getblockcount(), newheight)
          self.restart_node(1, extra_args=["-checkblocks=5"])
          wait_until(lambda: self.nodes[1].getblockcount() == newheight + 20)
          assert_equal(tip, self.nodes[1].getbestblockhash())
  
  
  if __name__ == '__main__':
      InvalidateTest().main()
  