`epiphany-textproj` projects a bundle to its canonical text and reads it back:
the header, identity, profile, extension, canonical-base and blob productions,
plus the pipeline that joins them to the operation layer already in place.
Free functions, not `TextValue` impls. `epiphany-bundle` does not depend on
`epiphany-core`, so the trait and the manifest types are both foreign to this
crate and the orphan rule forbids the impls. That looked like it would force a new
dependency edge until the productions were read properly: no document line
contains a `value` position, so none is needed. The bundle stays independent of
the music model, as designed.
Blobs are handled on both sides and neither is the obvious one. The emit side
filters `blob_roots` through a real reachability predicate that today provably
returns empty -- never the field wholesale, which is the plausible wrong answer.
The parse side rejects any blob line outright, while still parsing the production
in isolation so both halves are ready together. A trip-wire source-scans
epiphany-core and epiphany-ops for `BlobId` and names both obligations when it
fires; it asserts it actually scanned files, so it cannot pass vacuously.
Two rejections were added on the agents' own reading of the spec rather than the
brief, and both are right. Envelopes must already be in canonical reduction order
(text_projection.tex:458) -- without that, two texts differing only in envelope
order would denote one document. And a hand-built `TextDocument` carrying blobs is
refused rather than silently dropped, since serializing it would produce a bundle
whose next projection loses those bytes.
Section order is enforced as a sequence, not a set: a repeated or out-of-order
section is a rejection, never something the parser sorts back into place.
`derived-ordering` sorts and de-duplicates blob lines and extension chunk roots by
*rendered* form, proved against fixtures that are unsorted in memory rather than
already canonical -- the blind spot that let five outbound normalizations ship
untested in the operation layer.
Serialization stages payloads and lets `commit` assign every offset, hash and
chunk id, which is exactly what `req:textproj:derive-or-carry` assumes; nothing is
hashed by hand. The emitted bundle deliberately carries no accelerators.
And the three directions compose: `project(serialize(parse(T))) == T` holds
end-to-end over the companion's own worked example. Eight checks re-mutated
independently of the agents' reports, each killed by its own named test; all eight
document productions diffed against the grammar.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Levi Neuwirth
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