VS Code Extension

The Tova VS Code extension provides full language support for .tova files, including syntax highlighting, real-time diagnostics, code completion, and navigation.

Installation

From the Marketplace

Search for "Tova Language" in the VS Code Extensions panel (Ctrl+Shift+X / Cmd+Shift+X) and click Install.

Local Installation

To install from the source repository:

# From the tova-lang repository root
cd editors/vscode
npm install
code --install-extension .

Or package it as a .vsix file:

cd editors/vscode
npx vsce package
code --install-extension tova-lang-0.1.0.vsix

Features

Syntax Highlighting

The extension uses a TextMate grammar (syntaxes/tova.tmLanguage.json) to provide syntax highlighting for all Tova constructs:

• Keywords (fn, let, if, elif, else, match, for, while, return, etc.)
• Block keywords (shared, server, browser)
• Types and type annotations
• String literals with interpolation
• Comments
• Operators and punctuation
• JSX elements

LSP Integration

The extension automatically starts the Tova Language Server when you open a .tova file. This provides:

• Diagnostics -- Real-time error and warning markers as you type. Syntax errors, type warnings, and unused variable warnings appear inline with squiggly underlines and in the Problems panel.

• Completion -- Context-aware suggestions for keywords, built-in functions (print, len, range, sorted, etc.), Result/Option constructors (Ok, Err, Some, None), and identifiers defined in the current file.

• Go to Definition -- Ctrl+Click or F12 on any identifier to jump to its definition within the file.

• Hover -- Hover over any identifier to see type information and documentation. Built-in functions display their signature and description.

• Signature Help -- When typing a function call, a popup shows the function's parameter list and highlights the current parameter.

• Document Formatting -- Format the current file via Shift+Alt+F (Windows/Linux) or Shift+Option+F (macOS), or enable format-on-save in VS Code settings.

• Rename -- Rename symbols across the document with F2.

• Find References -- Find all references to a symbol with Shift+F12.

• Workspace Symbols -- Search for symbols across the workspace with Ctrl+T.

File Association

The extension automatically associates .tova files with the Tova language. Files with the .tova extension will use Tova syntax highlighting and LSP features.

The language configuration (language-configuration.json) defines:

• Comment toggling (// for line comments)
• Bracket matching and auto-closing
• Auto-closing pairs for strings and brackets
• Indentation rules

Configuration

The extension works with default settings out of the box. The LSP server is located relative to the extension at src/lsp/server.js and is started automatically using Bun.

Requirements

• Bun must be installed and available on your PATH. The LSP server runs as a Bun process.
• VS Code 1.75.0 or later.

Troubleshooting

If the language server fails to start:

1. Verify Bun is installed: bun --version
2. Check the Output panel in VS Code (select "Tova Language Server" from the dropdown)
3. Ensure the tova-lang package is properly installed

The LSP server includes crash recovery -- uncaught exceptions are logged rather than crashing the server process, so the extension should remain responsive even when processing files with errors.

Architecture

The extension consists of:

File	Purpose
package.json	Extension manifest, language contribution points
extension.js	LSP client that spawns the Tova language server
language-configuration.json	Bracket matching, comment toggling, indentation
syntaxes/tova.tmLanguage.json	TextMate grammar for syntax highlighting

The LSP client communicates with the server via stdio using the standard Language Server Protocol.