Make SelfVariableAccess a sub type of LocalVariableAccess

Author: hvitved

ruby/ql/lib/codeql/ruby/ast/Variable.qll

@@ -130,7 +130,7 @@ class VariableReadAccess extends VariableAccess {
 
 /** An access to a local variable. */
 class LocalVariableAccess extends VariableAccess instanceof LocalVariableAccessImpl {
-  final override string getAPrimaryQlClass() { result = "LocalVariableAccess" }
+  override string getAPrimaryQlClass() { result = "LocalVariableAccess" }
 
   /**
    * Holds if this access is a captured variable access. For example in
@@ -190,7 +190,7 @@ class ClassVariableWriteAccess extends ClassVariableAccess, VariableWriteAccess
 class ClassVariableReadAccess extends ClassVariableAccess, VariableReadAccess { }
 
 /** An access to the `self` variable */
-class SelfVariableAccess extends VariableAccess instanceof SelfVariableAccessImpl {
+class SelfVariableAccess extends LocalVariableAccess instanceof SelfVariableAccessImpl {
   final override string getAPrimaryQlClass() { result = "SelfVariableAccess" }
 }
 

ruby/ql/lib/codeql/ruby/ast/internal/AST.qll

@@ -698,7 +698,8 @@ class TVariableAccess =
   TLocalVariableAccess or TGlobalVariableAccess or TInstanceVariableAccess or
       TClassVariableAccess or TSelfVariableAccess;
 
-class TLocalVariableAccess = TLocalVariableAccessReal or TLocalVariableAccessSynth;
+class TLocalVariableAccess =
+  TLocalVariableAccessReal or TLocalVariableAccessSynth or TSelfVariableAccess;
 
 class TGlobalVariableAccess = TGlobalVariableAccessReal or TGlobalVariableAccessSynth;
 

ruby/ql/lib/codeql/ruby/ast/internal/Variable.qll

@@ -618,7 +618,7 @@ private class ClassVariableAccessSynth extends ClassVariableAccessRealImpl,
   final override string toString() { result = v.getName() }
 }
 
-abstract class SelfVariableAccessImpl extends VariableAccessImpl, TSelfVariableAccess { }
+abstract class SelfVariableAccessImpl extends LocalVariableAccessImpl, TSelfVariableAccess { }
 
 private class SelfVariableAccessReal extends SelfVariableAccessImpl, TSelfReal {
   private Ruby::Self self;

ruby/ql/lib/codeql/ruby/controlflow/internal/ControlFlowGraphImpl.qll

@@ -956,8 +956,6 @@ module Trees {
     final override ControlFlowTree getChildElement(int i) { result = this.getValue() and i = 0 }
   }
 
-  private class SelfTree extends LeafTree, Self { }
-
   private class SimpleParameterTree extends NonDefaultValueParameterTree, SimpleParameter { }
 
   // Corner case: For duplicated '_' parameters, only the first occurence has a defining