test: add Taproot support to script_builder #34473

1. 
   kannapoix commented at 6:30 am on February 2, 2026: none

   Make the script_builder used in unit tests compatible with Taproot by adding a PushSchnorrSig helper. Add a few tests that cover boundary values for Taproot SIGHASH flags in SignatureHashSchnorr (including values at and above 84, which were not covered by existing unit tests). This slightly improves unit test coverage of SignatureHashSchnorr, as suggested in issue #23279. Current unit test coverage for src/script/interpreter.cpp can be seen here: https://maflcko.github.io/b-c-cov/test_bitcoin.coverage/src/script/interpreter.cpp.gcov.html

   We also have Taproot tests in bip341_keypath_test_vectors, but extending those tests would require preparing a test data. Making script_builder Taproot-compatible is a simpler way to add edge-case tests for SignatureHashSchnorr and to add more Taproot unit tests later.

2. test: add Taproot support to script_builder

   Make the script_builder used in unit tests compatible with Taproot by
   adding a PushSchnorrSig helper. This is a simpler way to add edge-case
   tests than extending bip341_keypath_test_vectors, which would require
   preparing additional test data.
   
   Add tests for boundary values of Taproot SIGHASH flags in
   SignatureHashSchnorr, including cases where the SIGHASH value is
   greater than or equal to 84 that were not previously tested in unit tests.
   
   Addresses #23279.

   810228b76a
3. DrahtBot added the label Tests on Feb 2, 2026
4. 
   DrahtBot commented at 6:31 am on February 2, 2026: contributor

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   LLM Linter (✨ experimental)

   Possible places where named args for integral literals may be used (e.g. func(x, /*named_arg=*/0) in C++, and func(x, named_arg=0) in Python):

   • TestBuilder(CScript() « ToByteVector(keys.outputPubkey0.first), “Taproot key path spending”, SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_TAPROOT, false, WitnessMode::TAPROOT, 1, 1) in src/test/script_tests.cpp
   • TestBuilder(CScript() « ToByteVector(keys.outputPubkey0.first), “Taproot key path spending with unknown sighash 0x04”, SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_TAPROOT, false, WitnessMode::TAPROOT, 1, 1) in src/test/script_tests.cpp
   • TestBuilder(CScript() « ToByteVector(keys.outputPubkey0.first), “Taproot key path spending with unknown sighash 0x80”, SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_TAPROOT, false, WitnessMode::TAPROOT, 1, 1) in src/test/script_tests.cpp
   • TestBuilder(CScript() « ToByteVector(keys.outputPubkey0.first), “Taproot key path spending with unknown sighash 0x84”, SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_TAPROOT, false, WitnessMode::TAPROOT, 1, 1) in src/test/script_tests.cpp

   2026-02-02 06:31:33

5. DrahtBot added the label Needs rebase on Feb 2, 2026
6. 
   DrahtBot commented at 7:17 am on February 2, 2026: contributor

   🐙 This pull request conflicts with the target branch and needs rebase.

Contributors
kannapoix DrahtBot

Labels
Tests Needs rebase