A comment terminates a plain scalar, so a multi-line plain scalar cannot
resume after one. The parser accepted 'key: word1' then a '#' line then
' word2', and 'a' then 'b # ...' then 'c', merging the trailing content
back into the value ('word1 word2', 'a b c').
The scanner folds a genuine multi-line plain scalar into a single token
and splits it into a value-line scalar, an indent, and a further scalar
only when a comment broke its continuation folding. That token shape
therefore always denotes a comment-interrupted scalar, so the parser now
rejects it rather than re-merging. The re-merge path and its helper are
removed as they only ever served this malformed shape. A real multi-line
plain scalar and a trailing comment after a value stay valid.
Measured against the official YAML test-suite, parse-level conformance
rises from 264/333 (79.3%) to 266/333 (79.9%) with no regression.
Mihaela M
8649f1722a