internal/lsp/source: handle nil pointer in newBuiltinSignature

Fixes golang/go#40230 Change-Id: I457dd3ef009c9df9293f66871acdd90dcc6e1dcc Reviewed-on: https://go-review.googlesource.com/c/tools/+/242798 Run-TryBot: Rebecca Stambler <[email protected]> Reviewed-by: Robert Findley <[email protected]>
golang · Jul 15, 2020 · b42590c · b42590c
1 parent 9048b46
commit b42590c
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/internal/lsp/source/types_format.go b/internal/lsp/source/types_format.go
@@ -79,7 +79,11 @@ func newBuiltinSignature(ctx context.Context, view View, name string) (*signatur
 	if err != nil {
 		return nil, err
 	}
-	decl, ok := builtin.Package().Scope.Lookup(name).Decl.(*ast.FuncDecl)
+	obj := builtin.Package().Scope.Lookup(name)
+	if obj == nil {
+		return nil, fmt.Errorf("no builtin object for %s", name)
+	}
+	decl, ok := obj.Decl.(*ast.FuncDecl)
 	if !ok {
 		return nil, fmt.Errorf("no function declaration for builtin: %s", name)
 	}