test(dash): G1 difficulty/vardiff parity KAT vs p2pool-dash oracle

.github/workflows/build.yml

@@ -102,7 +102,7 @@ jobs:
                     core_test sharechain_test share_test btc_share_test \
                     test_threading test_weights \
                     test_header_chain test_mempool test_template_builder \
-                    test_doge_chain test_compact_blocks test_dash_x11_kat \
+                    test_doge_chain test_compact_blocks test_dash_x11_kat test_dash_g1_difficulty_parity \
                     test_dash_header_chain test_dash_block_replay test_dash_conformance test_dash_subsidy test_dash_mempool test_dash_simplifiedmns test_dash_quorum test_dash_quorum_root test_dash_mn_state test_dash_embedded_gbt test_dash_smldiff test_dash_p2p_messages test_dash_p2p_connection test_dash_p2p_node test_dash_node_interface test_dash_config test_dash_broadcaster test_dash_broadcaster_full test_dash_share_hash_link test_dash_block_relay test_dash_rpc_request test_dash_rpc_conf test_dash_block_producer test_dash_embedded_relay_e2e test_dash_block_relay_plan test_dash_version_activation_latch test_dash_block_relay_binding test_dash_block_relay_dual_arm test_dash_coinbase_parity test_dash_donation_combined test_dash_g3_assembled test_dash_work_target test_dash_work_job_targets test_dash_cb_payee test_dash_stratum_notify_roundtrip test_dash_poolnode_messages test_dash_peer test_dash_share_tracker test_dash_node test_dash_share_messages test_dash_stratum_extranonce_split \
                     test_multiaddress_pplns test_pplns_stress \
                     test_hash_link test_decay_pplns \

test/CMakeLists.txt

@@ -221,6 +221,19 @@ if (BUILD_TESTING AND GTest_FOUND)
     target_link_libraries(test_dash_x11_kat PRIVATE c2pool_payout c2pool_hashrate c2pool_merged_mining)  # OBJECT-lib SCC direct-naming (#22/#39): core stratum/web_server TUs
     gtest_add_tests(test_dash_x11_kat "" AUTO)
 
+    # DASH G1 difficulty/vardiff parity KAT (byte-parity vs oracle networks/dash.py).
+    # Links the same additive dash_x11 + core set as test_dash_x11_kat; pulls
+    # impl/dash/params.hpp + config_pool.hpp (sharechain SSOT); no ltc/pool SCC dep.
+    add_executable(test_dash_g1_difficulty_parity test_dash_g1_difficulty_parity.cpp)
+    target_link_libraries(test_dash_g1_difficulty_parity PRIVATE
+        GTest::gtest_main GTest::gtest
+        dash_x11 core
+        nlohmann_json::nlohmann_json
+        ${Boost_LIBRARIES}
+    )
+    target_link_libraries(test_dash_g1_difficulty_parity PRIVATE c2pool_payout c2pool_hashrate c2pool_merged_mining)  # OBJECT-lib SCC direct-naming (#22/#39)
+    gtest_add_tests(test_dash_g1_difficulty_parity "" AUTO)
+
     # DASH consensus known-answer test (PR-0 foundation, S3 slice): SPV
     # HeaderChain + DarkGravityWave v3 retarget. header_chain.hpp pulls in the
     # additive dash_x11 primitive (hash_x11.hpp) + core (uint256/leveldb/pack/log);

test/test_dash_g1_difficulty_parity.cpp

@@ -0,0 +1,94 @@
+// G1 difficulty/vardiff parity KAT — DASH sharechain target byte-parity vs the
+// DASH oracle frstrtr/p2pool-dash (networks/dash.py).
+//
+// FENCED conformance test (no production code touched). Test-form artifact of
+// greenlight gate G1 for the DASH difficulty/vardiff surface, mirroring the
+// dgb/bch g1_oracle_byte_parity KATs but scoped to the target math the DASH
+// migration plan calls out as independently-landable byte-parity groundwork
+// (integrator 2026-07-04: proceed on the G1 difficulty/vardiff parity KAT ahead
+// of the operator GO on the consensus-bearing flip).
+//
+// NON-CIRCULAR posture: the difficulty-target and coin-level (net.PARENT)
+// expected values below are typed from the oracle python source
+// (p2pool/dash/networks/dash.py), NOT re-read from the C++ SUT constant. A drift
+// in config_pool.hpp / params.hpp that silently diverges from the oracle fails
+// here even though sibling dash tests (which source the same SUT constant on both
+// sides) stay green.
+//
+// SCOPE LINE: the p2pool *sharechain* namespacing constants (IDENTIFIER/PREFIX)
+// are c2pool-chosen bucket-1 isolation primitives, ABSENT from the oracle PARENT.
+// They are pinned in IsolationPrimitivesRegressionGuard as a pure drift guard and
+// are explicitly NOT asserted as oracle-conformance.
+//
+// MUST appear in BOTH the ctest registration (test/CMakeLists.txt) AND the
+// build.yml --target allowlist, or it becomes a #143-style NOT_BUILT sentinel.
+
+#include <impl/dash/params.hpp>
+#include <impl/dash/config_pool.hpp>
+
+#include <core/coin_params.hpp>
+
+#include <gtest/gtest.h>
+
+namespace {
+
+// Oracle networks/dash.py:31  _DIFF1_TARGET = 0xFFFF * 2**208  (standard bdiff
+// difficulty-1 target). 0xFFFF left-shifted 208 bits, big-endian 256-bit:
+// 8 hex zeros + "ffff" + 52 hex zeros. Derived from the oracle FORMULA, not the
+// SUT literal, so a hand-edit of config_pool.hpp max_target() fails this pin.
+uint256 oracle_diff1_target()
+{
+    uint256 t;
+    t.SetHex("00000000ffff0000000000000000000000000000000000000000000000000000");
+    return t;
+}
+
+// max_target parity: the sharechain SSOT max_target() AND the plumbed CoinParams
+// field both equal the oracle bdiff-1 target.
+TEST(DashG1DifficultyParity, MaxTargetIsBdiff1_OracleDash)
+{
+    EXPECT_EQ(dash::SharechainConfig::max_target(), oracle_diff1_target());
+    core::CoinParams p = dash::make_coin_params(/*testnet=*/false);
+    EXPECT_EQ(p.max_target, oracle_diff1_target());
+}
+
+// SANE_TARGET_RANGE = (_DIFF1_TARGET//10000, _DIFF1_TARGET) (oracle dash.py:33).
+// Non-circular structural pins: easiest sane == max_target (oracle SANE[1]),
+// hardest sane is non-zero and strictly tighter than the easiest.
+TEST(DashG1DifficultyParity, SaneTargetRangeMatchesOracle)
+{
+    EXPECT_EQ(dash::SharechainConfig::sane_target_max(), dash::SharechainConfig::max_target());
+    EXPECT_NE(dash::SharechainConfig::sane_target_min(), uint256());
+    EXPECT_NE(dash::SharechainConfig::sane_target_min(), dash::SharechainConfig::max_target());
+}
+
+// Coin-level net.PARENT parity (oracle networks/dash.py mainnet).
+TEST(DashG1DifficultyParity, CoinLevelParentParity)
+{
+    core::CoinParams p = dash::make_coin_params(/*testnet=*/false);
+    EXPECT_EQ(p.symbol, "DASH");                 // dash.py:22 SYMBOL
+    EXPECT_EQ(p.block_period, 150u);             // dash.py:21 BLOCK_PERIOD
+    EXPECT_EQ(p.address_version, 76u);           // dash.py:12 ADDRESS_VERSION (X...)
+    EXPECT_EQ(p.address_p2sh_version, 16u);      // dash.py:13 SCRIPT_ADDRESS_VERSION (7...)
+    EXPECT_EQ(p.dust_threshold, 100000u);        // dash.py DUST_THRESHOLD = 0.001e8
+}
+
+// Testnet address divergence (oracle networks/dash_testnet.py), isolation
+// primitives shared — but this KAT only asserts the address versions here.
+TEST(DashG1DifficultyParity, TestnetAddressDiverges)
+{
+    core::CoinParams p = dash::make_coin_params(/*testnet=*/true);
+    EXPECT_EQ(p.address_version, 140u);          // testnet PUBKEY_ADDRESS (y...)
+    EXPECT_EQ(p.address_p2sh_version, 19u);      // testnet SCRIPT_ADDRESS
+}
+
+// Bucket-1 isolation-primitive REGRESSION GUARD — NOT oracle-conformance.
+// IDENTIFIER/PREFIX are c2pool-chosen sharechain namespacing (absent from the
+// oracle PARENT); pinned purely to catch silent namespace drift.
+TEST(DashG1DifficultyParity, IsolationPrimitivesRegressionGuard)
+{
+    EXPECT_EQ(dash::SharechainConfig::IDENTIFIER_HEX, "7242ef345e1bed6b");
+    EXPECT_EQ(dash::SharechainConfig::PREFIX_HEX,     "3b3e1286f446b891");
+}
+
+} // namespace