ExpressionTools loadContents how to load from array

CWL Questions
1

Hello!
I’m trying to concatenate the content of some small files using the ExpressionTool, but it seems that the loadContents doesn’t work on arrays, despite in the doc it includes arrays of files.

Here’s a small example to reproduce the error:

cwlVersion: v1.2

class: ExpressionTool
requirements:
  InlineJavascriptRequirement: {}
inputs:
  input_files: 
    type: File[]
    loadContents: true
  single_file:
    type: File
    loadContents: true
outputs:
  output_file:
    type: File
expression: |
 ${
   var out = { output_file :  { class : "File", basename : "test.txt" , contents : "" } }
   for (var i = 0; i < inputs.input_files.length; i++) {
       if ( inputs.input_files[i] ){
         if ( inputs.input_files[i].contents.match(out.output_file.contents) ){
             continue
         }
         out.output_file.contents += inputs.input_files[i].contents + "\n"
       }
   }
   return out 
 }

test.yaml:

input_files:
  - class: File
    location: test1.txt 
  - class: File
    location: test2.txt 
single_file:
  class: File
  location: test3.txt