Properly fetch pointer elements

pkg/tools/cidlc/check.go

@@ -336,7 +336,12 @@ func (chk *Checker) CheckIDLType(t types.Type, opts PropertyOptions) error {
 	case *types.Pointer:
 		// A pointer is OK so long as the field is either optional or a resource type.
 		if !opts.Optional {
-			if isres, _ := IsResource(nil, ft.Elem()); !isres {
+			elem := ft.Elem()
+			isres := false
+			if named, isnamed := elem.(*types.Named); isnamed {
+				isres, _ = IsResource(named.Obj(), named)
+			}
+			if !isres {
 				return errors.New("bad pointer; must be optional or a resource type")
 			}
 		}

pkg/tools/cidlc/types.go

@@ -7,6 +7,7 @@ import (
 	"reflect"
 
 	"github.com/pulumi/coconut/pkg/resource/idl"
+	"github.com/pulumi/coconut/pkg/util/contract"
 )
 
 func IsPrimitive(t types.Type) bool {
@@ -27,16 +28,18 @@ var (
 // IsResource checks whether a type is a special IDL resource.  If yes, it returns true for the first boolean, and the
 // second boolean indicates whether the resource is named or not.
 func IsResource(obj *types.TypeName, t types.Type) (bool, bool) {
-	// If a named type, fetch the underlying.
-	if n, is := t.(*types.Named); is {
-		t = n.Underlying()
-	}
+	contract.Assert(obj != nil)
 
 	// If this is a resource type itself, then we're done.
 	if isres, isname := isResourceObj(obj); isres {
 		return isres, isname
 	}
 
+	// If a named type, fetch the underlying.
+	if n, is := t.(*types.Named); is {
+		t = n.Underlying()
+	}
+
 	if s, is := t.(*types.Struct); is {
 		// Otherwise, it's a resource if it has an embedded resource field.
 		for i := 0; i < s.NumFields(); i++ {