document_from_bundle refused a base-bearing bundle, but the public
project_text_document did not. A caller holding a directly constructed
TextDocument could therefore emit a (canonical-base ...) line that
parse_document then rejects — a projector able to produce what the
parser refuses, which is precisely the asymmetry pin 3b exists to close
and which req:textproj:roundtrip's second equation quantifies over.
The guard had been placed on the path the pin happened to name rather
than on every path a caller can reach, and the unguarded one was the
only reachable half: no live Bundle can carry a canonical base during
the S28 -> P13-S27 interval, so the bundle-side refusal cannot fire
today, while the document-side path is one public call away. The new
corpus vector proved the hole existed rather than closing it — it is
built by projecting a base-bearing document.
project_text_document now returns Result and refuses. A crate-private
render_text_document keeps the unchecked formatter for its one
legitimate caller, the canonical_base_present negative vector: a
negative vector still has to contain the spelling it asserts is
refused, and producing those bytes is not the same as permitting them.
Every other vector goes through the checked projector.
projecting_a_base_bearing_text_document_is_refused locks both halves —
that the public projector refuses, and that the private renderer still
emits the section, since the reject vector silently stops carrying its
spelling otherwise. Mutation-verified: removing the refusal fails that
test and nothing else. Restored by hand.
The corpus is byte-identical, so no vector regenerated. Workspace green
at 1570.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QjsEnYhm1gPpf6ii2iFxFV