alternative implementation for resolving the sibling

src/main/resources/io/viash/platforms/nextflow/channel/_parseParamList.nf

@@ -87,24 +87,14 @@ def _parseParamList(param_list, Map config) {
   // The paths of input files inside a param_list file may have been specified relatively to the
   // location of the param_list file. These paths must be made absolute.
   if (paramListPath) {
-
-    // functionality to resolve a single path (as String) relative to the param_list file
-    // but only if the file does not specify a remote path 
-    def resolveIfNotRemote = { path, parentPath -> 
-      if (path instanceof String && FileHelper.getUrlProtocol(path) == null) {
-        return parentPath.resolveSibling(path) 
-      }
-      return path
-    }
-
     paramSets = paramSets.collect({ id, data ->
       def new_data = data.collectEntries{ parName, parValue ->
         def par = config.functionality.allArguments.find{it.plainName == parName}
         if (par && par.type == "file" && par.direction == "input") {
           if (parValue instanceof Collection) {
-            parValue = parValue.collect{path -> resolveIfNotRemote(path, paramListPath)}
+            parValue = parValue.collect{path -> _resolveSiblingIfNotAbsolute(path, paramListPath)}
           } else {
-            parValue = resolveIfNotRemote(parValue, paramListPath) 
+            parValue = _resolveSiblingIfNotAbsolute(parValue, paramListPath) 
           }
         }
         [parName, parValue]

src/main/resources/io/viash/platforms/nextflow/functions/_resolveSiblingIfNotAbsolute.nf

@@ -0,0 +1,19 @@
+/**
+  * Resolve a path relative to the current file.
+  * 
+  * @param str The path to resolve, as a String.
+  * @param parentPath The path to resolve relative to, as a Path.
+  *
+  * @return The path that may have been resovled, as a Path.
+  */
+
+def _resolveSiblingIfNotAbsolute(str, parentPath) {
+  if (str !instanceof String) {
+    return str
+  }
+  strAsPath = file(str, hidden: true, relative: true)
+  if (!strAsPath.isAbsolute()) {
+    return parentPath.resolveSibling(str) 
+  }
+  return strAsPath
+}