From f81fad5e0f3be1f7aed59f9da00396c75c2a6406 Mon Sep 17 00:00:00 2001 From: Sebastian Falbesoner Date: Mon, 1 Apr 2024 14:03:35 +0200 Subject: test: introduce and use `calculate_input_weight` helper Rather than manually estimating an input's weight by adding up all the involved components (fixed-size skeleton, compact-serialized lengths, and the actual scriptSig / witness stack items) we can simply take use of the serialization classes `CTxIn` / `CTxInWitness` instead, to achieve the same with significantly less code. The new helper is used in the functional tests rpc_psbt.py and wallet_send.py, where the previous manual estimation code was duplicated. --- test/functional/rpc_psbt.py | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) (limited to 'test/functional/rpc_psbt.py') diff --git a/test/functional/rpc_psbt.py b/test/functional/rpc_psbt.py index 016aa3ba11..897cb51b18 100755 --- a/test/functional/rpc_psbt.py +++ b/test/functional/rpc_psbt.py @@ -16,8 +16,6 @@ from test_framework.messages import ( CTxIn, CTxOut, MAX_BIP125_RBF_SEQUENCE, - WITNESS_SCALE_FACTOR, - ser_compact_size, ) from test_framework.psbt import ( PSBT, @@ -42,6 +40,7 @@ from test_framework.util import ( find_vout_for_address, ) from test_framework.wallet_util import ( + calculate_input_weight, generate_keypair, get_generate_key, ) @@ -752,17 +751,9 @@ class PSBTTest(BitcoinTestFramework): input_idx = i break psbt_in = dec["inputs"][input_idx] - # Calculate the input weight - # (prevout + sequence + length of scriptSig + scriptsig) * WITNESS_SCALE_FACTOR + len of num scriptWitness stack items + (length of stack item + stack item) * N stack items - # Note that occasionally this weight estimate may be slightly larger or smaller than the real weight - # as sometimes ECDSA signatures are one byte shorter than expected with a probability of 1/128 - len_scriptsig = len(psbt_in["final_scriptSig"]["hex"]) // 2 if "final_scriptSig" in psbt_in else 0 - len_scriptsig += len(ser_compact_size(len_scriptsig)) - len_scriptwitness = (sum([(len(x) // 2) + len(ser_compact_size(len(x) // 2)) for x in psbt_in["final_scriptwitness"]]) + len(ser_compact_size(len(psbt_in["final_scriptwitness"])))) if "final_scriptwitness" in psbt_in else 0 - len_prevout_txid = 32 - len_prevout_index = 4 - len_sequence = 4 - input_weight = ((len_prevout_txid + len_prevout_index + len_sequence + len_scriptsig) * WITNESS_SCALE_FACTOR) + len_scriptwitness + scriptsig_hex = psbt_in["final_scriptSig"]["hex"] if "final_scriptSig" in psbt_in else "" + witness_stack_hex = psbt_in["final_scriptwitness"] if "final_scriptwitness" in psbt_in else None + input_weight = calculate_input_weight(scriptsig_hex, witness_stack_hex) low_input_weight = input_weight // 2 high_input_weight = input_weight * 2 -- cgit v1.2.3