Merge pull request #21429 from github/tausbn/fix-bad-join-in-method-call-order

Python: Fix bad join in method call order computation

Author: tausbn

python/ql/src/Classes/CallsToInitDel/MethodCallOrder.qll

@@ -152,18 +152,23 @@ predicate missingCallToSuperclassMethod(Class base, Function shouldCall, string
  */
 predicate missingCallToSuperclassMethodRestricted(Class base, Function shouldCall, string name) {
   missingCallToSuperclassMethod(base, shouldCall, name) and
-  not exists(Class superBase |
-    // Alert only on the highest base class that has the issue
-    superBase = getADirectSuperclass+(base) and
-    missingCallToSuperclassMethod(superBase, shouldCall, name)
-  ) and
+  not superclassAlsoMissesCall(base, shouldCall, name) and
   not exists(Function subShouldCall |
     // Mention in the alert only the lowest method we're missing the call to
     subShouldCall.getScope() = getADirectSubclass+(shouldCall.getScope()) and
     missingCallToSuperclassMethod(base, subShouldCall, name)
   )
 }
 
+/**
+ * Holds if a strict superclass of `base` is also missing a call to `shouldCall` named `name`,
+ * indicating that `base` is not the highest class in the hierarchy with this issue.
+ */
+pragma[nomagic]
+private predicate superclassAlsoMissesCall(Class base, Function shouldCall, string name) {
+  missingCallToSuperclassMethod(getADirectSuperclass+(base), shouldCall, name)
+}
+
 /**
  * If `base` contains a `super()` call, gets a method in the inheritance hierarchy of `name` in the MRO of `base`
  * that does not contain a `super()` call, but would call `shouldCall` if it did, which does not otherwise get called