SLua LSP for VS Code

Language tooling for Second Life SLua (Luau), with a bundled language server:

• Syntax, supported type, builtin call, and common-mistake diagnostics.
• Completion, hover, signatures, symbols, and semantic highlighting.
• Definitions for locals, known members, and literal source modules.
• Local references, capture-safe rename, and quick fixes.
• Read-only preprocessing previews with navigation back to source.

Getting started

Use VS Code 1.90 or later. Install the built VSIX using Extensions: Install from VSIX…, then open a .lua, .luau, or .slua file. No separate server installation is needed.

Definitions and settings

Official Second Life definitions are bundled for offline use. Failed updates retain the last accepted definitions and are logged in SLua LSP.

Custom definitions take precedence; relative paths resolve from the workspace. Use SLua: Update LSL Definitions to refresh explicitly and SLua: Show Active LSL Definitions to inspect the selected file.

Source previews

SLua: Preview Preprocessed Source opens a read-only generated snapshot, including supported unsaved imports. F12 or SLua: Go to Original Source returns to a mapped source location. Changed/missing originals need a fresh preview; generated helpers have no source target.

Set slua.preprocessor.context to {} for file/line macros, or supply explicit agentId, agentName, and UTC ISO timestamp for identity/time macros. The default null disables macros. Invalid updates retain the last accepted context. Generation never uploads, executes, or saves your source.

Diagnostics

Quick Fix can repair supported dot/colon call separators or suppress one semantic diagnostic code on the next line. Existing directives are preserved. Suppression does not repair a program; parse errors cannot be suppressed.

truthy-literal explains that zero/empty text are true in Luau. ipairs-literal-hole identifies provably skipped entries in a literal table. Both are suppressible advice; valid iteration is not rejected.

Analysis covers a bounded SLua profile rather than the complete Luau type solver. Experimental syntax can require simulator flags. Known-member definitions are supported; arbitrary field references/rename and cross-file rename are not.

The extension does not synchronize with a viewer or execute scripts. See the repository CLI and compatibility guides for detailed boundaries.