Ruby: factor out isProcCreationCall

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

@@ -1333,16 +1333,20 @@ predicate lambdaCreation(Node creation, LambdaCallKind kind, DataFlowCallable c)
     creation.asExpr() =
       any(CfgNodes::ExprNodes::MethodCallCfgNode mc |
         c.asCallable() = mc.getBlock().getExpr() and
-        (
-          mc.getExpr().getMethodName() = ["lambda", "proc"]
-          or
-          mc.getExpr().getMethodName() = "new" and
-          mc.getReceiver().getExpr().(ConstantReadAccess).getAQualifiedName() = "Proc"
-        )
+        isProcCreationCall(mc.getExpr())
       )
   )
 }
 
+/** Holds if `call` is a call to `lambda`, `proc`, or `Proc.new` */
+pragma[nomagic]
+private predicate isProcCreationCall(MethodCall call) {
+  call.getMethodName() = ["proc", "lambda"]
+  or
+  call.getMethodName() = "new" and
+  call.getReceiver().(ConstantReadAccess).getAQualifiedName() = "Proc"
+}
+
 /**
  * Holds if `call` is a from-source lambda call of kind `kind` where `receiver`
  * is the lambda expression.