After `client.files_upload`, `message.file.size != message.file["size"]`

      message = client.files_upload(
        channels: '\#dev',
        as_user: true,
        file: UploadIO.new('./test.txt', 'text/plain'),
        title: 'test.txt',
        filename: 'test.txt',
        initial_comment: 'testing'
      )
      File.open('./test.txt').size # 27
      message.file.size # 35
      message.file["size"] # 27

message.file.size is then different from message.file["size"]. The latter is both what is shown when printing message.file to the console, and appears to be the actual size of the file. Not sure what the former actually is.

What's going on? Should this be what's going on?

Start by reproducing the client.files_upload example with UploadIO and inspect the returned message.file object, comparing its size method with the "size" value. Trace how the upload response is represented and determine whether both access paths should report the same size; done means the discrepancy is explained and the expected behavior is covered by a regression check.