Merge #15238: [QA] remove some magic mining constants in functional tests

b651ef7e1c submitheader: more directly test missing prev block header (Gregory Sanders)
1e7f741745 remove some magic mining constants in functional tests (Gregory Sanders)

Pull request description:

  The fewer magic numbers the better.

  Also more directly tested a `submitheader` case of bad previous blockhash.

Tree-SHA512: 52b01a6aa199fa909eea4e9e84409a901933e545724e33149cc4132c82168199fd678809b6d94d95c9ff6ad02238a9552363620d13b8beaa5d4b67ade9ef425c

3 files changed, 18 insertions, 14 deletions

diff --git a/test/functional/interface_rest.py b/test/functional/interface_rest.py
index f850a54462..a47a556406 100755
--- a/test/functional/interface_rest.py
+++ b/test/functional/interface_rest.py
@@ -22,6 +22,8 @@ from test_framework.util import (
     hex_str_to_bytes,
 )
 
+from test_framework.messages import BLOCK_HEADER_SIZE
+
 class ReqType(Enum):
     JSON = 1
     BIN = 2
@@ -214,26 +216,26 @@ class RESTTest (BitcoinTestFramework):
 
         # Check binary format
         response = self.test_rest_request("/block/{}".format(bb_hash), req_type=ReqType.BIN, ret_type=RetType.OBJ)
-        assert_greater_than(int(response.getheader('content-length')), 80)
+        assert_greater_than(int(response.getheader('content-length')), BLOCK_HEADER_SIZE)
         response_bytes = response.read()
 
         # Compare with block header
         response_header = self.test_rest_request("/headers/1/{}".format(bb_hash), req_type=ReqType.BIN, ret_type=RetType.OBJ)
-        assert_equal(int(response_header.getheader('content-length')), 80)
+        assert_equal(int(response_header.getheader('content-length')), BLOCK_HEADER_SIZE)
         response_header_bytes = response_header.read()
-        assert_equal(response_bytes[:80], response_header_bytes)
+        assert_equal(response_bytes[:BLOCK_HEADER_SIZE], response_header_bytes)
 
         # Check block hex format
         response_hex = self.test_rest_request("/block/{}".format(bb_hash), req_type=ReqType.HEX, ret_type=RetType.OBJ)
-        assert_greater_than(int(response_hex.getheader('content-length')), 160)
+        assert_greater_than(int(response_hex.getheader('content-length')), BLOCK_HEADER_SIZE*2)
         response_hex_bytes = response_hex.read().strip(b'\n')
         assert_equal(binascii.hexlify(response_bytes), response_hex_bytes)
 
         # Compare with hex block header
         response_header_hex = self.test_rest_request("/headers/1/{}".format(bb_hash), req_type=ReqType.HEX, ret_type=RetType.OBJ)
-        assert_greater_than(int(response_header_hex.getheader('content-length')), 160)
-        response_header_hex_bytes = response_header_hex.read(160)
-        assert_equal(binascii.hexlify(response_bytes[:80]), response_header_hex_bytes)
+        assert_greater_than(int(response_header_hex.getheader('content-length')), BLOCK_HEADER_SIZE*2)
+        response_header_hex_bytes = response_header_hex.read(BLOCK_HEADER_SIZE*2)
+        assert_equal(binascii.hexlify(response_bytes[:BLOCK_HEADER_SIZE]), response_header_hex_bytes)
 
         # Check json format
         block_json_obj = self.test_rest_request("/block/{}".format(bb_hash))
diff --git a/test/functional/mining_basic.py b/test/functional/mining_basic.py
index 661d9f4c97..5dafb11ac5 100755
--- a/test/functional/mining_basic.py
+++ b/test/functional/mining_basic.py
@@ -15,6 +15,7 @@ from test_framework.blocktools import create_coinbase
 from test_framework.messages import (
     CBlock,
     CBlockHeader,
+    BLOCK_HEADER_SIZE
 )
 from test_framework.mininode import (
     P2PDataStore,
@@ -131,10 +132,9 @@ class MiningTest(BitcoinTestFramework):
 
         self.log.info("getblocktemplate: Test bad tx count")
         # The tx count is immediately after the block header
-        TX_COUNT_OFFSET = 80
         bad_block_sn = bytearray(block.serialize())
-        assert_equal(bad_block_sn[TX_COUNT_OFFSET], 1)
-        bad_block_sn[TX_COUNT_OFFSET] += 1
+        assert_equal(bad_block_sn[BLOCK_HEADER_SIZE], 1)
+        bad_block_sn[BLOCK_HEADER_SIZE] += 1
         assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {'data': b2x(bad_block_sn), 'mode': 'proposal', 'rules': ['segwit']})
 
         self.log.info("getblocktemplate: Test bad bits")
@@ -164,9 +164,9 @@ class MiningTest(BitcoinTestFramework):
         assert_submitblock(bad_block, 'prev-blk-not-found', 'prev-blk-not-found')
 
         self.log.info('submitheader tests')
-        assert_raises_rpc_error(-22, 'Block header decode failed', lambda: node.submitheader(hexdata='xx' * 80))
-        assert_raises_rpc_error(-22, 'Block header decode failed', lambda: node.submitheader(hexdata='ff' * 78))
-        assert_raises_rpc_error(-25, 'Must submit previous header', lambda: node.submitheader(hexdata='ff' * 80))
+        assert_raises_rpc_error(-22, 'Block header decode failed', lambda: node.submitheader(hexdata='xx' * BLOCK_HEADER_SIZE))
+        assert_raises_rpc_error(-22, 'Block header decode failed', lambda: node.submitheader(hexdata='ff' * (BLOCK_HEADER_SIZE-2)))
+        assert_raises_rpc_error(-25, 'Must submit previous header', lambda: node.submitheader(hexdata=super(CBlock, bad_block).serialize().hex()))
 
         block.nTime += 1
         block.solve()
diff --git a/test/functional/test_framework/messages.py b/test/functional/test_framework/messages.py
index 356a45d6d0..4bd58519c5 100755
--- a/test/functional/test_framework/messages.py
+++ b/test/functional/test_framework/messages.py
@@ -28,7 +28,7 @@ import struct
 import time
 
 from test_framework.siphash import siphash256
-from test_framework.util import hex_str_to_bytes, bytes_to_hex_str
+from test_framework.util import hex_str_to_bytes, bytes_to_hex_str, assert_equal
 
 MIN_VERSION_SUPPORTED = 60001
 MY_VERSION = 70014  # past bip-31 for ping/pong
@@ -591,6 +591,8 @@ class CBlockHeader:
             % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
                time.ctime(self.nTime), self.nBits, self.nNonce)
 
+BLOCK_HEADER_SIZE = len(CBlockHeader().serialize())
+assert_equal(BLOCK_HEADER_SIZE, 80)
 
 class CBlock(CBlockHeader):
     __slots__ = ("vtx",)