move getAnInstanceMemberAccess to ClassNode

Author: erik-krogh

javascript/ql/src/semmle/javascript/dataflow/Nodes.qll

@@ -1007,6 +1007,31 @@ class ClassNode extends DataFlow::SourceNode {
     result = getAnInstanceReference(DataFlow::TypeTracker::end())
   }
 
+  /**
+   * Gets a property read that accesses the property `name` on an instance of this class.
+   *
+   * Concretely, this holds when the base is an instance of this class or a subclass thereof.
+   */
+  pragma[nomagic]
+  DataFlow::PropRead getAnInstanceMemberAccess(string name, DataFlow::TypeTracker t) {
+    result = this.getAnInstanceReference(t.continue()).getAPropertyRead(name)
+    or
+    exists(DataFlow::ClassNode subclass |
+      result = subclass.getAnInstanceMemberAccess(name, t) and
+      not exists(subclass.getInstanceMember(name, _)) and
+      this = subclass.getADirectSuperClass()
+    )
+  }
+
+  /**
+   * Gets a property read that accesses the property `name` on an instance of this class.
+   *
+   * Concretely, this holds when the base is an instance of this class or a subclass thereof.
+   */
+  DataFlow::PropRead getAnInstanceMemberAccess(string name) {
+    result = this.getAnInstanceMemberAccess(name, DataFlow::TypeTracker::end())
+  }
+
   /**
    * Gets an access to a static member of this class.
    */

javascript/ql/src/semmle/javascript/dataflow/internal/CallGraphs.qll

@@ -57,7 +57,7 @@ module CallGraph {
     exists(DataFlow::ClassNode cls |
       exists(string name |
         function = cls.getInstanceMethod(name) and
-        getAnInstanceMemberAccess(cls, name, t.continue()).flowsTo(result)
+        cls.getAnInstanceMemberAccess(name, t.continue()).flowsTo(result)
         or
         function = cls.getStaticMethod(name) and
         cls.getAClassReference(t.continue()).getAPropertyRead(name).flowsTo(result)
@@ -133,26 +133,6 @@ module CallGraph {
     )
   }
 
-  /**
-   * Gets a property read that accesses the property `name` on an instance of this class.
-   *
-   * Concretely, this holds when the base is an instance of this class or a subclass thereof.
-   *
-   * This predicate may be overridden to customize the class hierarchy analysis.
-   */
-  pragma[nomagic]
-  private DataFlow::PropRead getAnInstanceMemberAccess(
-    DataFlow::ClassNode cls, string name, DataFlow::TypeTracker t
-  ) {
-    result = cls.getAnInstanceReference(t.continue()).getAPropertyRead(name)
-    or
-    exists(DataFlow::ClassNode subclass |
-      result = getAnInstanceMemberAccess(subclass, name, t) and
-      not exists(subclass.getInstanceMember(name, _)) and
-      cls = subclass.getADirectSuperClass()
-    )
-  }
-
   /**
    * Gets a possible callee of `node` with the given `imprecision`.
    *