Address Ian's feedback - v2

snowplow · Jul 18, 2022 · 5ae6397 · 5ae6397
1 parent 83af36f
commit 5ae6397
Showing 1 changed file with 12 additions and 11 deletions.
diff --git a/modules/common/src/main/scala/com/snowplowanalytics/snowplow/rdbloader/common/S3.scala b/modules/common/src/main/scala/com/snowplowanalytics/snowplow/rdbloader/common/S3.scala
@@ -49,18 +49,19 @@ object S3 {
      * parent path doesn't match with sub path.
      */
     def diff(parent: Folder): Option[String] = {
-      val parentSplit = parent.split("/")
-      val subSplit = f.split("/")
-      val zipped = parentSplit.zip(subSplit)
-      if (zipped.length != parentSplit.length || zipped.length == subSplit.length) None
-      else {
-        val matched = zipped.foldLeft(true) {
-          case (false, _) => false
-          case (true, (s1, s2)) => s1 == s2
+      def go(parentParts: List[String], subParts: List[String]): Option[String] =
+        (parentParts, subParts) match {
+          case (_, Nil) =>
+            None
+          case (Nil, s) =>
+            Some(s.mkString("/"))
+          case (pHead :: _, sHead :: _) if pHead != sHead =>
+            None
+          case (pHead :: pTail, sHead :: sTail) if pHead == sHead =>
+            go(pTail, sTail)
         }
-        if (matched) Some(subSplit.drop(zipped.length).mkString("/"))
-        else None
-      }
+
+      go(parent.split("/").toList, f.split("/").toList)
     }
   }