F1 (round 1) wrapped the image alt in escapeLinkText, and that helper also guards
the link-form media captions (attachment/pdf/embed). But its character class
covered only stock CommonMark — NOT the Docmost inline EXTENSIONS this same PR
registers on the marked instance: highlight `==x==` (canon #7), math `$x$`
(canon #6), footnote `^[x]` (canon #2). Their triggers `= $ ^` are not CommonMark
punctuation, so an alt or media filename like `x $A$ y`, `use ==bold==`, `^[fn]`,
or `data $A$.csv` was silently turned into a math/highlight/footnote node on
import — the same class of round-trip data loss F1 closed, reintroduced by this
PR's own canon.
Fix: add `= $ ^` to the escapeLinkText class (`/[\\`*_~[\]<&!()=$^]/g`). `\= \$ \^`
decode back to literals (all ASCII punctuation) AND, being escape tokens, stop
the extension tokenizer from matching — verified lossless byte-stable round-trip.
Updated the helper comment to name the two trigger sets (CommonMark + Docmost
inline extensions). Extended the adversarial round-trip tests: image alt gains
`x $A$ y` / `5$ and 10$` / `use ==bold==` / `^[fn]` / `cost $5 == price`; pdf name
gains `data $A$.csv` / `q3 ==final==.pdf` / `5$ and 10$.pdf` / `note ^[x].pdf` —
all byte-stable with the node intact, so the hole can't reopen.
package vitest: 658 passed; tsc clean. git-sync: 268. mcp: 454.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Ten media/embed node types move their TOP-LEVEL serialization off raw schema
HTML onto a readable markdown target plus an always-emitted discriminator
comment whose NAME selects the node type. The schema-HTML form is retained on
the raw-HTML/columns path (comments are dropped by the DOM parse stage there).
image-form <!--name …--> youtube, video, audio, drawio, excalidraw
link-form [text](src)<!--name …--> pdf, attachment, embed (text=filename/provider)
standalone <!--pageembed …--> / <!--transclusion …--> pageEmbed, transclusionReference
The comment NAME is the node-type discriminator and is ALWAYS emitted, even when
the attr JSON is empty (`<!--youtube-->`), so a bare `` is never
mistaken for an `image` and a bare `[t](u)` stays a plain link — no URL-sniffing.
src rides in the markdown target; every other non-default attr (incl. the id
links attachmentId/sourcePageId/transclusionId) rides in the comment JSON
(stable key order, numerics stringified, align="center" omitted).
New src/lib/media-html.ts: byte-exact builders reproducing the schema HTML each
old processNode case returned. Both the serializer's raw-HTML path (blockToHtml,
now de-delegated from `return processNode(block)` to explicit per-type cases)
and the importer call these, so serialize and parse cannot drift.
Import (applyCommentDirectives): image-form binds the preceding <img> (src from
it), link-form the preceding <a> (src=href, text=filename/provider), standalone
replaces the comment (same leading-doc-level handling as #5). Each rebuilds the
schema element via the media-html builder, then swaps it in; the empty-<p> hoist
is absorbed by stripEmptyParagraphs. Fail-open: wrong element/position/name or
malformed JSON -> inert, no throw.
Link-form visible text is escaped (escapeLinkText) for the FULL set of
CommonMark inline-active punctuation (\ ` * _ ~ [ ] < & ! ( )), not just [ ] \:
the label is parsed as inline content, so a filename/provider like
`report *v2*.pdf` or `.pdf` would otherwise lose the markup (or
fragment the parse) when the importer reads a.textContent back — a data-loss
regression vs the old data-attachment-name form. Adversarial round-trip fixtures
lock byte- and value-stability for emphasis/code/strike/autolink/entity/image
markers and nested-link names.
Tests: new media-comments.test.ts (40 cases: per-type exact md + lossless
byte-stable round-trip incl. id links, minimal-node discriminator-still-emitted,
in-column schema-HTML form, discriminator integrity, fail-open, active-punct
filenames). Goldens in media-roundtrip / markdown-converter-golden /
markdown-converter / diagram-roundtrip updated to the md+comment form (columns
stay schema-HTML). The former known-limitation image-diagrams fixture is now
byte- AND canonically-stable (canon #8 omits the diagram align="center" default)
and was promoted from an it.fails into the green corpus (11-image-diagrams.json).
git-sync stabilize.test.ts: the "diagram materializes data-align=center" fixpoint
moved into a column (where the raw-HTML asymmetry still holds), since top level
is now byte-stable.
package vitest: 540 passed; tsc clean. git-sync: 268 passed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>