test: make assumeUTXO test capture the expected fatal error

The test is exercising the error, so it can capture it before
the test framework displays it on the console as an unforeseen
fatal error.

Author: furszy

src/test/validation_chainstatemanager_tests.cpp

@@ -10,6 +10,7 @@
 #include <rpc/blockchain.h>
 #include <sync.h>
 #include <test/util/chainstate.h>
+#include <test/util/logging.h>
 #include <test/util/random.h>
 #include <test/util/setup_common.h>
 #include <timedata.h>
@@ -659,8 +660,11 @@ BOOST_FIXTURE_TEST_CASE(chainstatemanager_snapshot_completion_hash_mismatch, Sna
     fs::path snapshot_chainstate_dir = gArgs.GetDataDirNet() / "chainstate_snapshot";
     BOOST_CHECK(fs::exists(snapshot_chainstate_dir));
 
-    res = WITH_LOCK(::cs_main, return chainman.MaybeCompleteSnapshotValidation());
-    BOOST_CHECK_EQUAL(res, SnapshotCompletionResult::HASH_MISMATCH);
+    {
+        ASSERT_DEBUG_LOG("failed to validate the -assumeutxo snapshot state");
+        res = WITH_LOCK(::cs_main, return chainman.MaybeCompleteSnapshotValidation());
+        BOOST_CHECK_EQUAL(res, SnapshotCompletionResult::HASH_MISMATCH);
+    }
 
     auto all_chainstates = chainman.GetAll();
     BOOST_CHECK_EQUAL(all_chainstates.size(), 1);