Any specific reason where you see  -  global.reportFolder = this.argv.reportFolder;  - not working ? 

a) absolute path
If user specifies an absolute path - reportFolder=/Users/a/b/c/report i.e absolute path, its anyways going to ignore global.workingDirectory.

b) relative path
If user specifies a relative path e.g reportFolder=a/b/c/report , it will create directory wrt global.workingDirectory anyways.