Fix initial value check on legacy sequence numbers#202
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A dumb bug, because the _comment_ in the code actually describes correct behavior. It just happened to work anyway because most OPC-UA servers set 1 as the initial value, because there's no apparent reason to pick any other number even if the standard allows it. This fixes it and also includes a proper test.
svanharmelen
approved these changes
Feb 23, 2026
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A dumb bug, because the comment in the code actually describes correct behavior. It just happened to work anyway
because most OPC-UA servers set 1 as the initial value, because there's no apparent reason to pick any other number even if the standard allows it. They even realized that this was stupid, and decided to fix it by introducing yet another way for sequence numbers to work, under the assumption that it will "eventually" get phased out as computing gets stronger and old security policies become deprecated.
This fixes it and also includes a proper test. The fix itself is trivial, just check
expected == self.min_value()instead ofincoming_sequence_number == self.min_value()... I also moved theis_legacycheck first, since technically that's more correct.Should fix #125.