test: check BlockStatus when InvalidateBlock is used

when a block is invalidated using InvalidateBlock, check that:
1. it's status is BLOCK_FAILED_VALID
2. it's children's status is BLOCK_FAILED_CHILD
   and not BLOCK_FAILED_VALID
3. it's ancestors are valid

Author: stratospher

src/test/blockchain_tests.cpp

@@ -117,4 +117,36 @@ BOOST_AUTO_TEST_CASE(num_chain_tx_max)
     BOOST_CHECK_EQUAL(block_index.m_chain_tx_count, std::numeric_limits<uint64_t>::max());
 }
 
+BOOST_FIXTURE_TEST_CASE(invalidate_block, TestChain100Setup)
+{
+    const CChain& active{*WITH_LOCK(Assert(m_node.chainman)->GetMutex(), return &Assert(m_node.chainman)->ActiveChain())};
+
+    // Check BlockStatus when doing InvalidateBlock()
+    BlockValidationState state;
+    auto* orig_tip = active.Tip();
+    int height_to_invalidate = orig_tip->nHeight - 10;
+    auto* tip_to_invalidate = active[height_to_invalidate];
+    m_node.chainman->ActiveChainstate().InvalidateBlock(state, tip_to_invalidate);
+
+    // tip_to_invalidate just got invalidated, so it's BLOCK_FAILED_VALID
+    WITH_LOCK(::cs_main, assert(tip_to_invalidate->nStatus & BLOCK_FAILED_VALID));
+    WITH_LOCK(::cs_main, assert((tip_to_invalidate->nStatus & BLOCK_FAILED_CHILD) == 0));
+
+    // check all ancestors of the invalidated block are validated up to BLOCK_VALID_TRANSACTIONS and are not invalid
+    auto pindex = tip_to_invalidate->pprev;
+    while (pindex) {
+        WITH_LOCK(::cs_main, assert(pindex->IsValid(BLOCK_VALID_TRANSACTIONS)));
+        WITH_LOCK(::cs_main, assert((pindex->nStatus & BLOCK_FAILED_MASK) == 0));
+        pindex = pindex->pprev;
+    }
+
+    // check all descendants of the invalidated block are BLOCK_FAILED_CHILD
+    pindex = orig_tip;
+    while (pindex && pindex != tip_to_invalidate) {
+        WITH_LOCK(::cs_main, assert((pindex->nStatus & BLOCK_FAILED_VALID) == 0));
+        WITH_LOCK(::cs_main, assert(pindex->nStatus & BLOCK_FAILED_CHILD));
+        pindex = pindex->pprev;
+    }
+}
+
 BOOST_AUTO_TEST_SUITE_END()