`Repr::Nonfinite(&'a str)` could only be produced by a deserializer that
borrows from its input, so the new wire spelling round-tripped through
`from_str` and `from_slice` and through nothing else. Measured on the
pre-fix head:
from_str {"Number":"inf"} -> Ok
from_str {"Number":"inf"} -> Err (the SAME JSON document)
to_value then from_value -> Err (does not round-trip its own output)
from_reader -> Err
The escaped form is the serious half: escaping is not a distinction JSON
makes, so the wire accepted a subset of the encodings of the spelling it
claims to share with the file. `Cow<'a, str>` fixes all four; the serialized
form is unchanged.
The PR's own tests could not see this — both use `from_str` exclusively,
which is precisely the one path that borrows. A check adjacent to the
question it names, inside the change that defines the question.
Also tightened `a_string_that_is_not_one_of_the_three_tokens_is_refused`: its
second disjunct accepted `data did not match any variant`, which is exactly
the message the above bug produces, so it passed in both worlds.
Conflict was `context/test-evidence/core.md` only, against #143. Both entries
kept and verified line-by-line — neither test cites the file, so a dropped
entry would pass `--check-evidence`.
Gates on the merge: 1728 passed / 0 failed / 7 ignored over 38 binaries,
clippy -D warnings clean, fmt clean, and `cargo check --target
wasm32-unknown-unknown -p improvise-core` clean — the one gate the review
asked for and could not run.
Found by adversarial review (confirmed by injection, not reasoned).
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FC2jVn8Au7E9JPkw6bwXXH
Edward Langley
f94fbedb85