Frontier scan tests

nano/core_test/CMakeLists.txt

@@ -11,6 +11,7 @@ add_executable(
   block_store.cpp
   block_processor.cpp
   bootstrap.cpp
+  bootstrap_frontier_scan.cpp
   bootstrap_server.cpp
   bucketing.cpp
   cli.cpp

nano/core_test/bootstrap_frontier_scan.cpp

@@ -0,0 +1,242 @@
+#include <nano/lib/blocks.hpp>
+#include <nano/lib/logging.hpp>
+#include <nano/lib/stats.hpp>
+#include <nano/lib/tomlconfig.hpp>
+#include <nano/node/bootstrap/bootstrap_service.hpp>
+#include <nano/node/bootstrap/frontier_scan.hpp>
+#include <nano/test_common/system.hpp>
+#include <nano/test_common/testutil.hpp>
+
+#include <gtest/gtest.h>
+
+#include <sstream>
+
+using namespace std::chrono_literals;
+
+namespace
+{
+struct test_context
+{
+	nano::stats stats;
+	nano::frontier_scan_config config;
+	nano::bootstrap::frontier_scan frontier_scan;
+
+	explicit test_context (nano::frontier_scan_config config_a = {}) :
+		stats{ nano::default_logger () },
+		config{ config_a },
+		frontier_scan{ config, stats }
+	{
+	}
+};
+}
+
+TEST (bootstrap_frontier_scan, construction)
+{
+	test_context ctx{};
+	auto & frontier_scan = ctx.frontier_scan;
+}
+
+TEST (bootstrap_frontier_scan, next_basic)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 2; // Two heads for simpler testing
+	config.consideration_count = 3;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	// First call should return first head, account number 1 (avoiding burn account 0)
+	auto first = frontier_scan.next ();
+	ASSERT_EQ (first.number (), 1);
+
+	// Second call should return second head, account number 0x7FF... (half the range)
+	auto second = frontier_scan.next ();
+	ASSERT_EQ (second.number (), nano::account{ "7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF" });
+
+	// Third call should return first head again, sequentially iterating through heads
+	auto third = frontier_scan.next ();
+	ASSERT_EQ (third.number (), 1);
+}
+
+TEST (bootstrap_frontier_scan, process_basic)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 1; // Single head for simpler testing
+	config.consideration_count = 3;
+	config.candidates = 5;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	// Get initial account to scan
+	auto start = frontier_scan.next ();
+	ASSERT_EQ (start.number (), 1);
+
+	// Create response with some frontiers
+	std::deque<std::pair<nano::account, nano::block_hash>> response;
+	response.push_back ({ nano::account{ 2 }, nano::block_hash{ 1 } });
+	response.push_back ({ nano::account{ 3 }, nano::block_hash{ 2 } });
+
+	// Process should not be done until consideration_count is reached
+	ASSERT_FALSE (frontier_scan.process (start, response));
+	ASSERT_FALSE (frontier_scan.process (start, response));
+
+	// Head should not advance before reaching `consideration_count` responses
+	ASSERT_EQ (frontier_scan.next (), 1);
+
+	// After consideration_count responses, should be done
+	ASSERT_TRUE (frontier_scan.process (start, response));
+
+	// Head should advance to next account and start subsequent scan from there
+	ASSERT_EQ (frontier_scan.next (), 3);
+}
+
+TEST (bootstrap_frontier_scan, range_wrap_around)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 1;
+	config.consideration_count = 1;
+	config.candidates = 1;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	auto start = frontier_scan.next ();
+
+	// Create response that would push next beyond the range end
+	std::deque<std::pair<nano::account, nano::block_hash>> response;
+	response.push_back ({ nano::account{ std::numeric_limits<nano::uint256_t>::max () }, nano::block_hash{ 1 } });
+
+	// Process should succeed and wrap around
+	ASSERT_TRUE (frontier_scan.process (start, response));
+
+	// Next account should be back at start of range
+	auto next = frontier_scan.next ();
+	ASSERT_EQ (next.number (), 1);
+}
+
+TEST (bootstrap_frontier_scan, cooldown)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 1;
+	config.consideration_count = 1;
+	config.cooldown = 250ms;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	// First call should succeed
+	auto first = frontier_scan.next ();
+	ASSERT_NE (first.number (), 0);
+
+	// Immediate second call should fail (return 0)
+	auto second = frontier_scan.next ();
+	ASSERT_EQ (second.number (), 0);
+
+	// After cooldown, should succeed again
+	std::this_thread::sleep_for (500ms);
+	auto third = frontier_scan.next ();
+	ASSERT_NE (third.number (), 0);
+}
+
+TEST (bootstrap_frontier_scan, candidate_trimming)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 1;
+	config.consideration_count = 2;
+	config.candidates = 3; // Only keep the lowest candidates
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	auto start = frontier_scan.next ();
+	ASSERT_EQ (start.number (), 1);
+
+	// Create response with more candidates than limit
+	// Response contains: 1, 4, 7, 10
+	std::deque<std::pair<nano::account, nano::block_hash>> response1;
+	for (int i = 0; i <= 9; i += 3)
+	{
+		response1.push_back ({ nano::account{ start.number () + i }, nano::block_hash{ static_cast<uint64_t> (i) } });
+	}
+	ASSERT_FALSE (frontier_scan.process (start, response1));
+
+	// Response contains: 1, 3, 5, 7, 9
+	std::deque<std::pair<nano::account, nano::block_hash>> response2;
+	for (int i = 0; i <= 8; i += 2)
+	{
+		response2.push_back ({ nano::account{ start.number () + i }, nano::block_hash{ static_cast<uint64_t> (i) } });
+	}
+	ASSERT_TRUE (frontier_scan.process (start, response2));
+
+	// After processing replies candidates should be ordered and trimmed
+	auto next = frontier_scan.next ();
+	ASSERT_EQ (next.number (), 5);
+}
+
+TEST (bootstrap_frontier_scan, heads_distribution)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 4;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	// Collect initial accounts from each head
+	std::vector<nano::account> initial_accounts;
+	for (int i = 0; i < 4; i++)
+	{
+		initial_accounts.push_back (frontier_scan.next ());
+	}
+
+	// Verify accounts are properly distributed across the range
+	for (size_t i = 1; i < initial_accounts.size (); i++)
+	{
+		ASSERT_GT (initial_accounts[i].number (), initial_accounts[i - 1].number ());
+	}
+}
+
+TEST (bootstrap_frontier_scan, invalid_response_ordering)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 1;
+	config.consideration_count = 1;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	auto start = frontier_scan.next ();
+
+	// Create response with out-of-order accounts
+	std::deque<std::pair<nano::account, nano::block_hash>> response;
+	response.push_back ({ nano::account{ start.number () + 2 }, nano::block_hash{ 1 } });
+	response.push_back ({ nano::account{ start.number () + 1 }, nano::block_hash{ 2 } }); // Out of order
+
+	// Should still process successfully
+	ASSERT_TRUE (frontier_scan.process (start, response));
+	ASSERT_EQ (frontier_scan.next (), start.number () + 2);
+}
+
+TEST (bootstrap_frontier_scan, empty_responses)
+{
+	nano::frontier_scan_config config;
+	config.head_parallelism = 1;
+	config.consideration_count = 2;
+	test_context ctx{ config };
+	auto & frontier_scan = ctx.frontier_scan;
+
+	auto start = frontier_scan.next ();
+
+	// Empty response should not advance head even after receiving `consideration_count` responses
+	std::deque<std::pair<nano::account, nano::block_hash>> empty_response;
+	ASSERT_FALSE (frontier_scan.process (start, empty_response));
+	ASSERT_FALSE (frontier_scan.process (start, empty_response));
+	ASSERT_EQ (frontier_scan.next (), start);
+
+	// Let the head advance
+	std::deque<std::pair<nano::account, nano::block_hash>> response;
+	response.push_back ({ nano::account{ start.number () + 1 }, nano::block_hash{ 1 } });
+	ASSERT_TRUE (frontier_scan.process (start, response));
+	ASSERT_EQ (frontier_scan.next (), start.number () + 1);
+
+	// However, after receiving enough empty responses, head should wrap around to the start
+	ASSERT_FALSE (frontier_scan.process (start, empty_response));
+	ASSERT_FALSE (frontier_scan.process (start, empty_response));
+	ASSERT_FALSE (frontier_scan.process (start, empty_response));
+	ASSERT_EQ (frontier_scan.next (), start.number () + 1);
+	ASSERT_TRUE (frontier_scan.process (start, empty_response));
+	ASSERT_EQ (frontier_scan.next (), start); // Wraps around
+}