Ruby: move OptionalContentSet to TypeTrackerSpecific.qll

Author: asgerf

ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowPublic.qll

@@ -336,23 +336,13 @@ module Content {
   AttributeNameContent getAttributeName(string name) { result.getName() = name }
 }
 
-class OptionalContentSet extends TOptionalContentSet {
-  /** Gets a textual representation of this content set. */
-  string toString() {
-    result = "no content" // overridden in `ContentSet`
-  }
-
-  /** Holds if this is the special "no content set" value. */
-  predicate isNoContentSet() { this instanceof TNoContentSet }
-}
-
 /**
  * An entity that represents a set of `Content`s.
  *
  * The set may be interpreted differently depending on whether it is
  * stored into (`getAStoreContent`) or read from (`getAReadContent`).
  */
-class ContentSet extends OptionalContentSet, TContentSet {
+class ContentSet extends TContentSet {
   /** Holds if this content set is the singleton `{c}`. */
   predicate isSingleton(Content c) { this = TSingletonContent(c) }
 
@@ -365,7 +355,8 @@ class ContentSet extends OptionalContentSet, TContentSet {
    */
   predicate isElementLowerBound(int lower) { this = TElementLowerBoundContent(lower) }
 
-  override string toString() {
+  /** Gets a textual representation of this content set. */
+  string toString() {
     exists(Content c |
       this.isSingleton(c) and
       result = c.toString()

ruby/ql/lib/codeql/ruby/typetracking/TypeTrackerSpecific.qll

@@ -17,7 +17,15 @@ class TypeTrackingNode = DataFlowPublic::LocalSourceNode;
 
 class TypeTrackerContent = DataFlowPublic::ContentSet;
 
-class OptionalTypeTrackerContent = DataFlowPublic::OptionalContentSet;
+class OptionalTypeTrackerContent extends DataFlowPrivate::TOptionalContentSet {
+  /** Gets a textual representation of this content set. */
+  string toString() {
+    this instanceof DataFlowPrivate::TNoContentSet and
+    result = "no content"
+    or
+    result = this.(DataFlowPublic::ContentSet).toString()
+  }
+}
 
 /**
  * Holds if a value stored with `storeContents` can be read back with `loadContents`.
@@ -28,7 +36,7 @@ predicate compatibleContents(TypeTrackerContent storeContents, TypeTrackerConten
 }
 
 /** Gets the "no content set" value to use for a type tracker not inside any content. */
-OptionalTypeTrackerContent noContent() { result.isNoContentSet() }
+OptionalTypeTrackerContent noContent() { result = DataFlowPrivate::TNoContentSet() }
 
 /** Holds if there is a simple local flow step from `nodeFrom` to `nodeTo` */
 predicate simpleLocalFlowStep = DataFlowPrivate::localFlowStepTypeTracker/2;