TOON Tools for VS Code

Token-Oriented Object Notation support: syntax highlighting, formatting, linting, intelligent editing, previews, table viewer, and dual-marketplace publishing.

TOON Tools turns .toon files into a first-class VS Code editing experience for compact tabular data. It supports authoring, diagnostics, JSON conversion, data inspection, size analysis, and CSV export without leaving the editor.

Features

Feature	Description
Syntax highlighting	TextMate grammar for block names, row counts, fields, comments, quoted strings, empty values, and separators.
Formatter	Normalizes headers, row indentation, comma spacing, and trailing whitespace.
Linter	Reports row-count mismatches, duplicate fields, and rows with the wrong number of values.
Hover	Shows block metadata on headers and field names on data-row cells.
Inlay hints	Displays field-name hints before row values, controlled by `toon.inlayHints.enabled`.
Rename and definition	Rename block or field names from headers, and jump from rows back to the block header.
JSON conversion	Convert JSON arrays or objects of arrays to TOON, and convert TOON back to JSON.
Table Viewer	Inspect blocks as sortable, filterable tables in a VS Code-themed webview.
Size Analyzer	Compare TOON and JSON byte counts, line counts, and token estimates.
CSV export	Export any TOON block to a CSV file from the command palette or context menu.

Preview

Syntax Highlighting & Inlay Hints

Syntax highlighting and inlay hints

Table Viewer

Sortable, filterable table viewer

Hover & Diagnostics

Hover tooltips and live diagnostics

Install

Install from the VS Code Marketplace or Open VSX. To install a local VSIX build, run:

code --install-extension toon-tools-vsx-1.0.0.vsix

Usage

Open a .toon file to enable syntax highlighting, diagnostics, hover, inlay hints, formatting, and navigation. Use the command palette for conversion, preview, table inspection, token-size analysis, and CSV export commands.

TOON Format Specification

TOON stores tabular records as named blocks:

users[3]{id,name,role}:
  1,Alice,admin
  2,Bob,user
  3,Charlie,user

Header syntax:

BlockName[rowCount]{field1,field2,...}:

Rows are indented comma-separated values. Empty values are allowed. Double-quoted values may contain commas, and embedded quotes are escaped by doubling them:

users[2]{id,name,note}:
  1,"Bob, Jr.","Says ""hello"""
  2,Alice,

Comments start with # when the line begins with optional whitespace. See docs/toon-spec.md for the complete grammar and examples.

Configuration

Setting	Default	Description
`toon.linter.enabled`	`true`	Enable real-time TOON linting.
`toon.linter.debounceMs`	`300`	Debounce delay in milliseconds for linting on document changes.
`toon.formatter.indentWidth`	`2`	Number of spaces for row indentation. Allowed values: `2`, `4`.
`toon.formatter.fieldSpacing`	`compact`	Header field separator style: `compact` or `spaced`.
`toon.conversion.toJsonValueMode`	`strings`	TOON-to-JSON value mode: `strings` or `typed`.
`toon.inlayHints.enabled`	`true`	Show field-name inlay hints in data rows.
`toon.statusBar.enabled`	`true`	Show the current TOON block count in the VS Code status bar.

.toonrc files are validated against schemas/toon-config.schema.json.

Commands

Command	Description	Default shortcut
`TOON: Convert JSON to TOON`	Convert the active JSON document or selection into a TOON preview.	None
`TOON: Convert TOON to JSON`	Convert the active TOON document or selection into formatted JSON.	None
`TOON: Open JSON Preview (side)`	Open a side-by-side JSON preview for the active TOON document.	None
`TOON: Open TOON Preview (side)`	Open a side-by-side TOON preview for the active JSON document.	None
`TOON: Open Table Viewer`	Open the active TOON document in a sortable table viewer.	None
`TOON: Analyze Size / Tokens`	Compare TOON and JSON byte counts and token estimates.	None
`TOON: Export Block as CSV`	Export a selected TOON block to CSV.	None

Extension Development

git clone https://github.com/oaslananka/toon-tools-vsx.git
cd toon-tools-vsx
corepack enable
pnpm install --frozen-lockfile
pnpm run build

Launch the extension with F5 and the Launch TOON Extension configuration.

Useful local gates:

pnpm run format:check
pnpm run lint
pnpm run typecheck
pnpm run test:unit:coverage
pnpm run build
pnpm run package

Automation and scheduled repository checks are documented in docs/automation.md.

Workspace Trust and Security

TOON Tools declares limited untrusted-workspace support. Linting, formatting, syntax highlighting, hover, and inlay hints work in untrusted workspaces. The extension metadata marks conversion commands as trust-sensitive because they read document content and can create derived documents. Preview, table-viewer, size analysis, and CSV export commands also process active document content and can create webviews or files; use them only for workspace content you trust.

Webviews use VS Code theme variables, localResourceRoots, a restrictive Content-Security-Policy, and nonces generated with Node crypto.

Known Limitations

This extension implements a strict TOON table-block subset. Quoted row values support commas and escaped double quotes. TOON-to-JSON conversion keeps values as strings by default; opt into typed primitive inference with toon.conversion.toJsonValueMode. JSON-to-TOON conversion expects arrays of objects or objects containing arrays of objects, and object keys must be valid TOON block and field names.

Support

Open bugs, feature requests, and security-adjacent hardening requests in GitHub Issues. For private vulnerability reports, use GitHub private vulnerability reporting or a private security advisory.

Contributing

See docs/contributing.md.

License

MIT. See LICENSE.

TOON Tools VSX

oaslananka