PGP Dash-Escaped Text is still parsed for pgp

[bwbroersma]

PGP Dash-Escaped Text is still parsed for the PGP signature. Note that the File Format Description and ABNF Grammar of RFC 9116 explicitly only allows - in the cleartext part, not the signature. Specific problematic code that currently only checks if it's signed and not still reading the hash-header:

sectxt/sectxt/__init__.py

Lines 135 to 137 in 79bb386

	# signed content might be dash escaped
	if self._signed and not self._reading_sig and line.startswith("- "):
	line = line[2:]

Solution would be some cleartext variable to be set and reset per line if - is parsed, not to parse - -----END PGP SIGNATURE----- as valid, which is currently the case. There seems to be no need to ever use - escaping in sectxt, since all lined should either start with a field name or # comment. Probably it is there to be compatible with other PGP tooling.

[DigitalTrustCenter]

With the new release a pgp formatter checker is added using the PGPy module which checks the OpenPGP message specification in accordance with RFC 4880.
A dash escape within the signature will result in a pgp_data_error