Merge pull request #596 from moosq/hover-for-functionlike-obj

Hover for functions, altsteps and testcases

internal/lsp/hover.go

@@ -1,37 +1,77 @@
 package lsp
 
 import (
+	"bytes"
 	"context"
 	"strings"
 
 	"github.com/nokia/ntt/internal/lsp/protocol"
 	"github.com/nokia/ntt/ttcn3"
 	"github.com/nokia/ntt/ttcn3/ast"
+	"github.com/nokia/ntt/ttcn3/printer"
 )
 
+func getSignature(def *ttcn3.Definition) string {
+	var sig bytes.Buffer
+	switch node := def.Node.(type) {
+	case *ast.FuncDecl:
+		sig.WriteString(node.Kind.Lit + " " + node.Name.String())
+		printer.Print(&sig, def.FileSet, node.Params)
+		if node.RunsOn != nil {
+			sig.WriteString("\n  ")
+			printer.Print(&sig, def.FileSet, node.RunsOn)
+		}
+		if node.System != nil {
+			sig.WriteString("\n  ")
+			printer.Print(&sig, def.FileSet, node.System)
+		}
+		if node.Return != nil {
+			sig.WriteString("\n  ")
+			printer.Print(&sig, def.FileSet, node.Return)
+		}
+	}
+	return sig.String()
+}
+
 func (s *Server) hover(ctx context.Context, params *protocol.HoverParams) (*protocol.Hover, error) {
 	var (
-		file    = string(params.TextDocument.URI.SpanURI())
-		line    = int(params.Position.Line) + 1
-		col     = int(params.Position.Character) + 1
-		comment string
+		file      = string(params.TextDocument.URI.SpanURI())
+		line      = int(params.Position.Line) + 1
+		col       = int(params.Position.Character) + 1
+		comment   string
+		signature string
+		defFound  = false
 	)
 
 	tree := ttcn3.ParseFile(file)
 	x := tree.ExprAt(tree.Pos(line, col))
 	if x == nil {
 		return nil, nil
 	}
+
 	for _, def := range tree.LookupWithDB(x, &s.db) {
+		defFound = true
+
 		if firstTok := ast.FirstToken(def.Node); firstTok == nil {
 			continue
 		} else {
 			// make line breaks conform to markdown spec
 			comment = strings.ReplaceAll(firstTok.Comments(), "\n", "  \n")
+			signature = getSignature(def)
 		}
 	}
-
-	hoverContents := protocol.MarkupContent{Kind: "markdown", Value: comment}
+	if !defFound {
+		// look for predefined functions
+		if id := ast.Name(x); len(id) > 0 {
+			for _, predef := range PredefinedFunctions {
+				if predef.Label == id+"(...)" {
+					comment = predef.Documentation
+					signature = predef.Signature
+				}
+			}
+		}
+	}
+	hoverContents := protocol.MarkupContent{Kind: "markdown", Value: "```typescript\n" + string(signature) + "\n```\n - - -\n" + comment}
 	hover := &protocol.Hover{Contents: hoverContents}
 
 	return hover, nil