Create FreshNameGenerator class

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/astcreation/AstCreator.scala

@@ -27,7 +27,6 @@ class AstCreator(
     with AstForExpressionsCreator
     with AstForFunctionsCreator
     with AstForTypesCreator
-    with FreshVariableCreator
     with AstSummaryVisitor
     with AstNodeBuilder[RubyNode, AstCreator] {
 

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/astcreation/AstForExpressionsCreator.scala

@@ -7,9 +7,12 @@ import io.joern.x2cpg.{Ast, Defines as XDefines, ValidationMode}
 import io.joern.rubysrc2cpg.passes.Defines
 import io.shiftleft.codepropertygraph.generated.nodes.*
 import io.shiftleft.codepropertygraph.generated.{ControlStructureTypes, DispatchTypes, Operators, PropertyNames}
+import io.joern.rubysrc2cpg.utils.FreshNameGenerator
 
 trait AstForExpressionsCreator(implicit withSchemaValidation: ValidationMode) { this: AstCreator =>
 
+  val tmpGen = FreshNameGenerator(i => s"<tmp-$i>")
+
   protected def astForExpression(node: RubyNode): Ast = node match
     case node: StaticLiteral            => astForStaticLiteral(node)
     case node: HereDocNode              => astForHereDoc(node)
@@ -176,7 +179,7 @@ trait AstForExpressionsCreator(implicit withSchemaValidation: ValidationMode) {
     val block = blockNode(node)
     scope.pushNewScope(BlockScope(block))
 
-    val tmp = SimpleIdentifier(Option(className))(node.span.spanStart(freshVariableName()))
+    val tmp = SimpleIdentifier(Option(className))(node.span.spanStart(tmpGen.fresh))
     def tmpIdentifier = {
       val tmpAst = astForSimpleIdentifier(tmp)
       tmpAst.root.collect { case x: NewIdentifier => x.typeFullName(receiverTypeFullName) }
@@ -393,7 +396,7 @@ trait AstForExpressionsCreator(implicit withSchemaValidation: ValidationMode) {
     val block = blockNode(node)
     scope.pushNewScope(BlockScope(block))
 
-    val tmp = freshVariableName()
+    val tmp = tmpGen.fresh
 
     val argumentAsts = node.elements.flatMap(elem =>
       elem match

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/astcreation/AstForFunctionsCreator.scala

@@ -7,9 +7,12 @@ import io.joern.x2cpg.utils.NodeBuilders.{newClosureBindingNode, newLocalNode, n
 import io.joern.x2cpg.{Ast, AstEdge, ValidationMode, Defines as XDefines}
 import io.shiftleft.codepropertygraph.generated.nodes.*
 import io.shiftleft.codepropertygraph.generated.{EdgeTypes, EvaluationStrategies, ModifierTypes, NodeTypes}
+import io.joern.rubysrc2cpg.utils.FreshNameGenerator
 
 trait AstForFunctionsCreator(implicit withSchemaValidation: ValidationMode) { this: AstCreator =>
 
+  val procParamGen = FreshNameGenerator(i => Left(s"<proc-param-$i>"))
+
   /** Creates method declaration related structures.
     * @param node
     *   the node to create the AST structure from.
@@ -40,7 +43,7 @@ trait AstForFunctionsCreator(implicit withSchemaValidation: ValidationMode) { th
     )
 
     if (methodName == XDefines.ConstructorMethodName) scope.pushNewScope(ConstructorScope(fullName))
-    else scope.pushNewScope(MethodScope(fullName, Left(freshVariableName(i => s"<proc-param-$i>"))))
+    else scope.pushNewScope(MethodScope(fullName, procParamGen.fresh))
 
     val parameterAsts = astForParameters(node.parameters)
 
@@ -271,7 +274,7 @@ trait AstForFunctionsCreator(implicit withSchemaValidation: ValidationMode) { th
           astParentFullName = scope.surroundingScopeFullName
         )
 
-        scope.pushNewScope(MethodScope(fullName, Left(freshVariableName(i => s"<proc-param-$i>"))))
+        scope.pushNewScope(MethodScope(fullName, procParamGen.fresh))
 
         val thisParameterAst = Ast(
           newThisParameterNode(

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/astcreation/AstForStatementsCreator.scala

@@ -160,7 +160,7 @@ trait AstForStatementsCreator(implicit withSchemaValidation: ValidationMode) { t
     }
     def generatedNode: StatementList = node.expression
       .map { e =>
-        val tmp = SimpleIdentifier(None)(e.span.spanStart(freshVariableName()))
+        val tmp = SimpleIdentifier(None)(e.span.spanStart(tmpGen.fresh))
         StatementList(
           List(SingleAssignment(tmp, "=", e)(e.span)) ++
             goCase(Some(tmp))

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/astcreation/AstForTypesCreator.scala

@@ -125,7 +125,7 @@ trait AstForTypesCreator(implicit withSchemaValidation: ValidationMode) { this:
       astParentType = scope.surroundingAstLabel,
       astParentFullName = scope.surroundingScopeFullName
     )
-    scope.pushNewScope(MethodScope(fullName, Left("")))
+    scope.pushNewScope(MethodScope(fullName, procParamGen.fresh))
     val block_ = blockNode(node)
     scope.pushNewScope(BlockScope(block_))
     // TODO: Should it be `return this.@abc`?
@@ -155,7 +155,7 @@ trait AstForTypesCreator(implicit withSchemaValidation: ValidationMode) { this:
       astParentType = scope.surroundingAstLabel,
       astParentFullName = scope.surroundingScopeFullName
     )
-    scope.pushNewScope(MethodScope(fullName, Left("")))
+    scope.pushNewScope(MethodScope(fullName, procParamGen.fresh))
     val parameter = parameterInNode(node, "x", "x", 1, false, EvaluationStrategies.BY_REFERENCE)
     val methodBody = {
       val block_ = blockNode(node)

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/parser/RubyNodeCreator.scala

@@ -8,19 +8,15 @@ import org.antlr.v4.runtime.tree.{ParseTree, RuleNode}
 import io.joern.x2cpg.Defines as XDefines;
 
 import scala.jdk.CollectionConverters.*
+import io.joern.rubysrc2cpg.utils.FreshNameGenerator
 
 /** Converts an ANTLR Ruby Parse Tree into the intermediate Ruby AST.
   */
 class RubyNodeCreator extends RubyParserBaseVisitor[RubyNode] {
 
-  private var classCounter: Int = 0
-
-  private def tmpClassTemplate(id: Int): String = s"<anon-class-$id>"
-
+  private val classNameGen = FreshNameGenerator(id => s"<anon-class-$id>")
   protected def freshClassName(span: TextSpan): SimpleIdentifier = {
-    val name = tmpClassTemplate(classCounter)
-    classCounter += 1
-    SimpleIdentifier(None)(span.spanStart(name))
+    SimpleIdentifier(None)(span.spanStart(classNameGen.fresh))
   }
 
   private def defaultTextSpan(code: String = ""): TextSpan = TextSpan(None, None, None, None, code)

joern-cli/frontends/rubysrc2cpg/src/main/scala/io/joern/rubysrc2cpg/utils/FreshNameGenerator.scala

@@ -0,0 +1,10 @@
+package io.joern.rubysrc2cpg.utils
+
+class FreshNameGenerator[T](template: Int => T) {
+  private var counter: Int = 0
+  def fresh: T = {
+    val name = template(counter)
+    counter += 1
+    name
+  }
+}