Fixing failing tests.

Author: staudtMarius

src/main/java/edu/ie3/datamodel/io/IoUtil.java

@@ -37,7 +37,14 @@ public static String harmonizeFileSeparator(String in) {
    * @return the option for a harmonized path
    */
   public static Path harmonizeFileSeparator(Path path) {
-    return Path.of(IoUtil.harmonizeFileSeparator(path.toString()));
+    String in = path.toString();
+
+    if (in.length() > 0 && FILE_SEPARATOR_REGEX.contains(in.substring(0, 1))) {
+      in = in.replaceFirst("^" + IoUtil.FILE_SEPARATOR_REGEX, "");
+    }
+
+    return Path.of(
+        IoUtil.harmonizeFileSeparator(in.replaceAll(IoUtil.FILE_SEPARATOR_REGEX + "$", "")));
   }
 
   /**

src/test/groovy/edu/ie3/datamodel/io/source/csv/CsvTestDataMeta.groovy

@@ -51,6 +51,6 @@ trait CsvTestDataMeta {
   FileNamingStrategy fileNamingStrategy = new FileNamingStrategy()
 
   Path getResourceAbs(String directory) {
-    return Path.of(getClass().getResource(directory).toURI())
+    return Path.of(CsvTestDataMeta.getResource(directory).toURI())
   }
 }