3e9c736a26 test: fix accurate multisig sigop count (BIP16), add unit test (Sebastian Falbesoner)
Pull request description:
In the course of reviewing #29589 I noticed the following buggy call-site of `CScriptOp.decode_op_n` in the CScript's `GetSigOpCount` method:
4cc99df44a/test/functional/test_framework/script.py (L591-L593)
This should be `lastOpcode` rather than `opcode`. The latter is either OP_CHECKMULTISIG or OP_CHECKMULTISIGVERIFY at this point, so `decode_op_n` would result in an error. Also, in `CScript.raw_iter`, we have to return the op as `CScriptOp` type instead of a bare integer, otherwise we can't call the decode method on it. To prevent this in the future, add some simple unit tests for `GetSigOpCount`.
Note that this was unnoticed, as the code part was never hit so far in the test framework.
ACKs for top commit:
achow101:
ACK 3e9c736a26
Christewart:
ACK 3e9c736a26
rkrux:
tACK [3e9c736](3e9c736a26)
hernanmarino:
tACK 3e9c736a26
Tree-SHA512: 51647bb6d462fbd101effd851afdbd6ad198c0567888cd4fdcac389a9fb4bd3d7e648095c6944fd8875d36272107ebaabdc62d0e2423289055588c12294d05a7
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