dash: add CbTx version 2 support (#794)

electrumx/lib/tx_dash.py

@@ -211,23 +211,30 @@ class DashProUpRevTx(namedtuple("DashProUpRevTx",
         )
 
 
-class DashCbTx(namedtuple("DashCbTx", "version height merkleRootMNList")):
+class DashCbTx(namedtuple("DashCbTx", "version height merkleRootMNList "
+                                      "merkleRootQuorums")):
     '''Class representing DIP4 coinbase special tx'''
     def serialize(self):
         assert len(self.merkleRootMNList) == 32
-        return (
+        res = (
             pack_le_uint16(self.version) +              # version
             pack_le_uint32(self.height) +               # height
             self.merkleRootMNList                       # merkleRootMNList
         )
+        if self.version > 1:
+            assert len(self.merkleRootQuorums) == 32
+            res += self.merkleRootQuorums               # merkleRootQuorums
+        return res
 
     @classmethod
     def read_tx_extra(cls, deser):
-        return DashCbTx(
-            deser._read_le_uint16(),                    # version
-            deser._read_le_uint32(),                    # height
-            deser._read_nbytes(32)                      # merkleRootMNList
-        )
+        version = deser._read_le_uint16()
+        height = deser._read_le_uint32()
+        merkleRootMNList = deser._read_nbytes(32)
+        merkleRootQuorums = b''
+        if version > 1:
+            merkleRootQuorums = deser._read_nbytes(32)
+        return DashCbTx(version, height, merkleRootMNList, merkleRootQuorums)
 
 
 class DashSubTxRegister(namedtuple("DashSubTxRegister",

tests/lib/test_tx_dash.py

@@ -29,6 +29,18 @@ CB_TX = (
     'c15e2d1aa337c942000000000000000000000000260100c407040076629a6e42fb5191'
     '88f65889fd3ac0201be87aa227462b5643e8bb2ec1d7a82a')
 
+CB_TX_V2 = (
+    '0300050001000000000000000000000000000000000000000000000000000000000000'
+    '0000ffffffff1303c407040e2f5032506f6f6c2d74444153482fffffffff0448d6a73d'
+    '000000001976a914293859173a34194d445c2962b97383e2a93d7cb288ac22fc433e00'
+    '0000001976a914bf09c602c6b8f1db246aba5c37ad1cfdcb16b15e88ace9259c000000'
+    '00004341047559d13c3f81b1fadbd8dd03e4b5a1c73b05e2b980e00d467aa9440b29c7'
+    'de23664dde6428d75cafed22ae4f0d302e26c5c5a5dd4d3e1b796d7281bdc9430f35ac'
+    '00000000000000002a6a28be61411c3c79b7fd45923118ba74d340afb248ae2edafe78'
+    'c15e2d1aa337c942000000000000000000000000460200c407040076629a6e42fb5191'
+    '88f65889fd3ac0201be87aa227462b5643e8bb2ec1d7a82a76629a6e42fb519188f658'
+    '89fd3ac0201be87aa227462b5643e8bb2ec1d7a82a')
+
 
 PRO_REG_TX = (
     '030001000335f1c2ca44a1eb72e59f589df2852caacba39b7c0a5e61967f6b71d7a763'
@@ -201,6 +213,25 @@ def test_dash_tx_cb_tx():
     assert ser == test
 
 
+def test_dash_tx_cb_tx_v2():
+    test = bfh(CB_TX_V2)
+    deser = lib_tx_dash.DeserializerDash(test)
+    tx = deser.read_tx()
+    assert tx.version == 3
+    assert tx.tx_type == 5
+    extra = tx.extra_payload
+    assert extra.version == 2
+    assert extra.height == 264132
+    assert len(extra.merkleRootMNList) == 32
+    assert extra.merkleRootMNList == bfh(
+        '76629a6e42fb519188f65889fd3ac0201be87aa227462b5643e8bb2ec1d7a82a')
+    assert len(extra.merkleRootQuorums) == 32
+    assert extra.merkleRootQuorums == bfh(
+        '76629a6e42fb519188f65889fd3ac0201be87aa227462b5643e8bb2ec1d7a82a')
+    ser = tx.serialize()
+    assert ser == test
+
+
 def test_dash_tx_pro_reg_tx():
     test = bfh(PRO_REG_TX)
     deser = lib_tx_dash.DeserializerDash(test)