Make VariableAccess "abstract"

ql/src/codeql_ruby/ast/Variable.qll

@@ -60,15 +60,13 @@ class LocalVariable extends Variable {
 }
 
 /** An access to a variable. */
-class VariableAccess extends Expr, @token_identifier {
+class VariableAccess extends Expr {
   override VariableAccess::Range range;
 
   /** Gets the variable this identifier refers to. */
   Variable getVariable() { result = range.getVariable() }
 
   final override string toString() { result = this.getVariable().getName() }
-  // TODO uncomment this and fix the params test
-  //override string getAPrimaryQlClass() { result = "VariableAccess" }
 }
 
 /** An access to a local variable. */

ql/src/codeql_ruby/ast/internal/Variable.qll

@@ -227,20 +227,18 @@ module LocalVariable {
 }
 
 module VariableAccess {
-  class Range extends Expr::Range, @token_identifier {
-    override Generated::Identifier generated;
-    Variable variable;
-
-    Range() { access(this, variable) }
-
-    Variable getVariable() { result = variable }
+  abstract class Range extends Expr::Range {
+    abstract Variable getVariable();
   }
 }
 
 module LocalVariableAccess {
-  class Range extends VariableAccess::Range {
-    override LocalVariable variable;
+  class Range extends VariableAccess::Range, @token_identifier {
+    override Generated::Identifier generated;
+    LocalVariable variable;
 
-    override LocalVariable getVariable() { result = variable }
+    Range() { access(this, variable) }
+
+    final override LocalVariable getVariable() { result = variable }
   }
 }