add more conditions for inherit compatible

Author: chen ruixiang

Diff for: src/types.ts

@@ -6,7 +6,8 @@
 import {
   Class,
   Program,
-  DecoratorFlags
+  DecoratorFlags,
+  ElementKind
 } from "./program";
 
 import {
@@ -475,6 +476,26 @@ export class Type {
     return false;
   }
 
+  /** Tests if a value of this class is compatible to the target class / interface in the multi extends / implements situation. */
+  isInheritCompatibleTo(target: Type | null): bool {
+    if (target) {
+      if (this.isInternalReference && target.isInternalReference && this.isManaged && target.isManaged) {
+        let thisClass = this.getClass();
+        let targetClass = target.getClass();
+        if (thisClass && targetClass) {
+          // extends ThisClass implements TargetInterface
+          // implements ThisInterface, TargetInterface
+          if (thisClass.kind == ElementKind.CLASS || thisClass.kind == ElementKind.INTERFACE) {
+            if (targetClass.kind == ElementKind.INTERFACE) {
+              return true;
+            }
+          }
+        }
+      }
+    }
+    return false;
+  }
+
   /** Tests if a value of this type is assignable to the target type excl. implicit conversion. */
   isStrictlyAssignableTo(target: Type, signednessIsRelevant: bool = false): bool {
     if (this.isReference) return this.isAssignableTo(target);
@@ -941,7 +962,7 @@ export class Signature {
     } else {
       // check kind of `this` type
       if (thisThisType) {
-        if (!targetThisType || thisThisType.kind != targetThisType.kind || thisThisType.isReference != targetThisType.isReference) {
+        if (!thisThisType.isInheritCompatibleTo(targetThisType)) {
           return false;
         }
       } else if (targetThisType) {