FFS-MD for Visual Studio Code

Highlighting for FFS-MD — the FFS in-house Markdown dialect. This extension does not replace VS Code's Markdown support; it injects the FFS-specific tokens on top of the built-in Markdown grammar, so your .md files keep all their normal Markdown highlighting and additionally light up the FFS constructs.

Features

Injected on top of text.html.markdown:

• Block directives [IMAGE:…], [VIDEO: …], [SVG: …], [LIST:…] — the directive keyword, the inner path/label, and the | / , field separators each get their own scope. Prefixes are matched exactly ([IMAGE: has no space, [VIDEO: has one).
• Status marks (/) (x) (!) (?) (y) (n) (on) (off) — only these exact literals, never an arbitrary (word).
• Emoji shortcodes :name: (curated set plus ISO country-code flags).
• Footnotes [^label] references and [^label]: definitions.
• fson fenced code: inside a fson block the code is highlighted with the FSON grammar (source.fson) when the companion **FSON** extension (vscode-fson`) is installed.

Install

Marketplace (publisher Fedem): search FFS-MD in the Extensions view, or

code --install-extension Fedem.vscode-ffsmd

From a .vsix (e.g. the one hosted on <https://fson.fedem.eu>): download it, then code --install-extension vscode-ffsmd-<version>.vsix, or in VS Code use the Extensions view → ⋯ → Install from VSIX….

For FSON fenced-code colors, also install the FSON extension (Fedem.vscode-fson).

For development, open this folder and press <kbd>F5</kbd>, then open a .md file from corpus/ffsmd/.

How the injection is scoped

The grammar's injectionSelector targets Markdown content and avoids comments, strings, and already-embedded blocks. FFS directives are left-injected (L:) so they take priority over Markdown's generic [link] parsing. The injection only adds FFS token scopes — it never overrides the base Markdown highlighting, so headings, emphasis, lists, code, and VS Code's own YAML front-matter coloring all keep working exactly as they do in a plain Markdown file.

Formatting

FFS-MD has no canonical Markdown writer (the FFS renderer only produces HTML), so this formatter is deliberately conservative and render-neutral: format(x) renders to the same HTML as x. It normalizes only what is provably safe and never rewrites Markdown structure.

What it normalizes:

• FFS directive fields — [IMAGE:…], [VIDEO: …], [SVG: …], [LIST:…] have their |/,-separated fields trimmed to the compact canonical form (e.g. [IMAGE: a | b | c ] → [IMAGE:a|b|c]). This is exactly what the FFS renderer parses — it trims these fields itself — so the output is unchanged. Empty fields (||) and the exact prefixes ([IMAGE: no space, [VIDEO: one space) are preserved.
• Front-matter — key: value → key: value in the top-of-file --- block.
• Trailing whitespace — removed (outside fenced code).
• Blank-line runs — three or more blank lines collapse to two.
• Final newline — the file ends with exactly one.

What it never touches: fenced-code content (kept byte-for-byte, including inner whitespace and blank lines), GFM table rows, and all Markdown structure — heading style, list markers, ordered numbering, emphasis markers, blockquotes, indentation, and line wrapping.

Use it via the FFS-MD: Format Document (FFS-MD) command, or turn on ffsmd.format.enable to make it the Markdown document formatter for Format Document / format-on-save. It is off by default so it does not affect every Markdown file automatically.

Notes

• MD→FSON embedding (Markdown highlighted inside an FSON |-block) is intentionally out of scope; only fson→Markdown (fenced blocks) is handled here.
• Because this is an injection into every Markdown file, all .md files will recognize FFS tokens. If that is too broad for your workspace, you can disable the extension per-workspace.

Development

npm install
npm test              # formatter tests + inline scope tests + corpus snapshots
npm run test:formatter   # formatter golden + corpus idempotency only
npm run test:update   # regenerate corpus snapshots after grammar changes

Tests use vscode-tmgrammar-test against the project's real corpus/ffsmd/ files. The base Markdown and FSON grammars used by the tests live under test/grammars/.

License

MIT