Merge bitcoin/bitcoin#22378: test: remove confusing `MAX_BLOCK_BASE_SIZE`

607076d01bf23c69ac21950c17b01fb4e1130774 test: remove confusing `MAX_BLOCK_BASE_SIZE` (Sebastian Falbesoner)
4af97c74edcda56cd15523bf3a335adea2bad14a test: introduce `get_weight()` helper for CBlock (Sebastian Falbesoner)
a084ebe1330bcec15715e08b0f65319142927ad1 test: introduce `get_weight()` helper for CTransaction (Sebastian Falbesoner)

Pull request description:

  This is a very late follow-up PR to #10618, which removed the constant `MAX_BLOCK_BASE_SIZE` from the core implementation about four years ago (see also #10608 in why it was considered confusing and superfluous).
  Since there is also no point in still keeping it in the functional test framework, the PR switches to weight-based accounting on the relevant test code parts and use `MAX_BLOCK_WEIGHT` instead for the block limit checks. To prepare that, the first two commits introduce `get_weight()` helpers for the classes CTransaction and CBlock, respectively.

ACKs for top commit:
  MarcoFalke:
    review ACK 607076d01bf23c69ac21950c17b01fb4e1130774 🚴

Tree-SHA512: d59aa0b6b3dfd0a849b8063e66de275d252f705f99e25cd3bf6daec028b47d946777ee5b42a060f5283cb18e917ac073119c2c0e11bbc21211f69ef0a6ed335a

1 files changed, 14 insertions, 4 deletions

diff --git a/test/functional/test_framework/messages.py b/test/functional/test_framework/messages.py
index 0523627cef..57a2c7da47 100755
--- a/test/functional/test_framework/messages.py
+++ b/test/functional/test_framework/messages.py
@@ -33,7 +33,7 @@ from test_framework.siphash import siphash256
 from test_framework.util import assert_equal
 
 MAX_LOCATOR_SZ = 101
-MAX_BLOCK_BASE_SIZE = 1000000
+MAX_BLOCK_WEIGHT = 4000000
 MAX_BLOOM_FILTER_SIZE = 36000
 MAX_BLOOM_HASH_FUNCS = 50
 
@@ -608,12 +608,15 @@ class CTransaction:
                 return False
         return True
 
-    # Calculate the virtual transaction size using witness and non-witness
+    # Calculate the transaction weight using witness and non-witness
     # serialization size (does NOT use sigops).
-    def get_vsize(self):
+    def get_weight(self):
         with_witness_size = len(self.serialize_with_witness())
         without_witness_size = len(self.serialize_without_witness())
-        return math.ceil(((WITNESS_SCALE_FACTOR - 1) * without_witness_size + with_witness_size) / WITNESS_SCALE_FACTOR)
+        return (WITNESS_SCALE_FACTOR - 1) * without_witness_size + with_witness_size
+
+    def get_vsize(self):
+        return math.ceil(self.get_weight() / WITNESS_SCALE_FACTOR)
 
     def __repr__(self):
         return "CTransaction(nVersion=%i vin=%s vout=%s wit=%s nLockTime=%i)" \
@@ -761,6 +764,13 @@ class CBlock(CBlockHeader):
             self.nNonce += 1
             self.rehash()
 
+    # Calculate the block weight using witness and non-witness
+    # serialization size (does NOT use sigops).
+    def get_weight(self):
+        with_witness_size = len(self.serialize(with_witness=True))
+        without_witness_size = len(self.serialize(with_witness=False))
+        return (WITNESS_SCALE_FACTOR - 1) * without_witness_size + with_witness_size
+
     def __repr__(self):
         return "CBlock(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x nTime=%s nBits=%08x nNonce=%08x vtx=%s)" \
             % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,