Capabilities

Auto Detection

If your handler implements HoverHandler, go-lsp advertises hover support. If it implements CompletionResolveHandler, completion resolve support is included.

Capability Options

Use server options when editors need more detail than an interface can express.

srv := server.NewServer(h,
    server.WithCompletionOptions(lsp.CompletionOptions{
        TriggerCharacters: []string{".", ":"},
    }),
    server.WithSignatureHelpOptions(lsp.SignatureHelpOptions{
        TriggerCharacters:   []string{"("},
        RetriggerCharacters: []string{","},
    }),
    server.WithCodeActionOptions(lsp.CodeActionOptions{
        CodeActionKinds: []lsp.CodeActionKind{lsp.CodeActionQuickFix},
    }),
)

Commands

Advertise command IDs for workspace/executeCommand. This pairs well with extension actions such as generating a debug bundle.

srv := server.NewServer(h,
    server.WithExecuteCommandOptions(lsp.ExecuteCommandOptions{
        Commands: []string{"mylang.generateDebugBundle"},
    }),
)

Semantic Tokens

Semantic tokens need a legend so clients can decode token type and modifier indexes.

srv := server.NewServer(h,
    server.WithSemanticTokensOptions(lsp.SemanticTokensOptions{
        Legend: lsp.SemanticTokensLegend{
            TokenTypes:     []string{"type", "function", "variable"},
            TokenModifiers: []string{"declaration", "readonly"},
        },
    }),
)

File Operation Filters

srv := server.NewServer(h,
    server.WithFileOperationFilters([]lsp.FileOperationFilter{
        {Pattern: lsp.FileOperationPattern{Glob: "**/*.mylang"}},
    }),
)

Position Encoding

LSP defaults to UTF-16 positions. If your server deliberately uses another LSP 3.17 position encoding, advertise it explicitly.

srv := server.NewServer(h,
    server.WithPositionEncoding(lsp.PositionEncodingUTF8),
)