Hover support for local funcs

Implemented cache store in the server to handle hover for local
function.

internal/lsp/cache.go

@@ -0,0 +1,46 @@
+package lsp
+
+import (
+	cmap "github.com/orcaman/concurrent-map/v2"
+)
+
+type Cache struct {
+	pkgs cmap.ConcurrentMap[string, *Package]
+}
+
+func (c *Cache) lookupSymbol(pkgPath, symbol string) (*Symbol, bool) {
+	pkg, ok := c.pkgs.Get(pkgPath)
+	if !ok {
+		return nil, false
+	}
+
+	for _, s := range pkg.Symbols {
+		if s.Name == symbol {
+			return s, true
+		}
+	}
+	return nil, false
+}
+
+func NewCache() *Cache {
+	return &Cache{
+		pkgs: cmap.New[*Package](),
+	}
+}
+
+func (s *server) UpdateCache(pkgPath string) {
+	files, err := ListGnoFiles(pkgPath)
+	if err != nil {
+		// Ignore error
+		return
+	}
+	symbols := []*Symbol{}
+	for _, file := range files {
+		symbols = append(symbols, getSymbols(file)...)
+	}
+	s.cache.pkgs.Set(pkgPath, &Package{
+		Name:       pkgPath,
+		ImportPath: "",
+		Symbols:    symbols,
+	})
+}

internal/lsp/general.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"errors"
 	"log/slog"
+	"path/filepath"
 
 	"go.lsp.dev/jsonrpc2"
 	"go.lsp.dev/protocol"
@@ -24,6 +25,7 @@ func (s *server) DidOpen(ctx context.Context, reply jsonrpc2.Replier, req jsonrp
 	s.snapshot.file.Set(uri.Filename(), file)
 
 	slog.Info("open " + string(params.TextDocument.URI.Filename()))
+	s.UpdateCache(filepath.Dir(string(params.TextDocument.URI.Filename())))
 	notification := s.publishDiagnostics(ctx, s.conn, file)
 	return reply(ctx, notification, nil)
 }

internal/lsp/hover.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"go/ast"
 	"log/slog"
+	"path/filepath"
 	"strings"
 
 	"go.lsp.dev/jsonrpc2"
@@ -57,7 +58,22 @@ func (s *server) Hover(ctx context.Context, reply jsonrpc2.Replier, req jsonrpc2
 		slog.Info("hover - CALL_EXPR")
 		switch v := e.Fun.(type) {
 		case *ast.Ident:
-			// TODO: is a func? handle.
+			// TODO: don't show methods
+			pkgPath := filepath.Dir(params.TextDocument.URI.Filename())
+			sym, ok := s.cache.lookupSymbol(pkgPath, v.Name)
+			if !ok {
+				return reply(ctx, nil, nil)
+			}
+			return reply(ctx, protocol.Hover{
+				Contents: protocol.MarkupContent{
+					Kind:  protocol.Markdown,
+					Value: sym.String(),
+				},
+				Range: posToRange(
+					int(params.Position.Line),
+					[]int{0, 4},
+				),
+			}, nil)
 		case *ast.SelectorExpr:
 			// case pkg.Func
 			i, ok := v.X.(*ast.Ident)

internal/lsp/server.go

@@ -21,6 +21,7 @@ type server struct {
 
 	snapshot        *Snapshot
 	completionStore *CompletionStore
+	cache           *Cache
 
 	formatOpt tools.FormattingOption
 }
@@ -38,6 +39,7 @@ func BuildServerHandler(conn jsonrpc2.Conn, env *env.Env) jsonrpc2.Handler {
 
 		snapshot:        NewSnapshot(),
 		completionStore: InitCompletionStore(dirs),
+		cache:           NewCache(),
 
 		formatOpt: tools.Gofumpt,
 	}