Language Server

Language Server

Wippy includes a built-in LSP (Language Server Protocol) server that provides IDE features for Lua code. The server runs as part of the Wippy runtime and connects to editors via TCP or HTTP.

Features

• Code completion with type-aware suggestions
• Hover information showing types and signatures
• Go to definition
• Find references
• Document and workspace symbols
• Call hierarchy (incoming and outgoing calls)
• Real-time diagnostics (parse errors, type errors)
• Signature help for function parameters

Configuration

Enable the LSP server in .wippy.yaml:

version: "1.0"

lua:
  type_system:
    enabled: true

lsp:
  enabled: true
  address: ":7777"

Configuration Fields

Field	Default	Description
enabled	false	Enable the TCP server
address	:7777	TCP listen address
http_enabled	false	Enable the HTTP transport
http_address	:7778	HTTP listen address
http_path	/lsp	HTTP endpoint path
http_allow_origin	*	CORS allowed origin
max_message_bytes	8388608	Max incoming message size (bytes)

TCP Transport

The TCP server speaks JSON-RPC 2.0 with standard LSP message framing (Content-Length headers). This is the primary transport for editor integrations.

HTTP Transport

The HTTP transport accepts POST requests with JSON-RPC payloads. Useful for browser-based editors and web tools. CORS headers are included for cross-origin access.

lsp:
  enabled: true
  http_enabled: true
  http_address: ":7778"
  http_path: "/lsp"
  http_allow_origin: "*"

Document URI Scheme

The LSP server uses the wippy:// URI scheme to identify registry entries:

wippy://namespace:entry_name

Editors map these URIs to entry IDs in the registry. Both wippy:// scheme and raw namespace:entry_name formats are accepted.

Indexing

The LSP server maintains an index of all code entries for fast lookups. Indexing happens in the background using multiple workers.

Key behaviors:

• Entries are indexed in dependency order (dependencies first)
• Changes trigger re-indexing of affected entries
• Unsaved editor changes are stored in an overlay
• Index is incremental - only changed entries are re-processed

Supported LSP Methods

Method	Description
initialize	Capability negotiation
textDocument/didOpen	Track opened documents
textDocument/didChange	Full document sync
textDocument/didClose	Release documents
textDocument/hover	Type info at cursor
textDocument/definition	Jump to definition
textDocument/references	Find all references
textDocument/completion	Code completion
textDocument/signatureHelp	Function signatures
textDocument/diagnostic	File diagnostics
textDocument/documentSymbol	File symbols
workspace/symbol	Global symbol search
textDocument/prepareCallHierarchy	Call hierarchy
callHierarchy/incomingCalls	Find callers
callHierarchy/outgoingCalls	Find callees

Completion

The completion engine resolves types through the code graph. It provides:

• Member completion after . and : (fields, methods)
• Local variable completion
• Module-level symbol completion
• Trigger characters: ., :

Diagnostics

Diagnostics are computed during indexing and include:

• Parse errors (syntax problems)
• Type checking errors (mismatches, undefined symbols)
• Severity levels: error, warning, information, hint

Diagnostics update as you type through the document overlay system.

See Also

• Linter - CLI-based code checking
• Types - Type system documentation
• Configuration - Runtime configuration