Check 'package.json' syntax

[zanerock]

Overview

Bash rollup looks for options in the local package.json, but if the file has syntax errors, you can get an erroneous error message. So, we should pro-actively check the syntax of the file as a preamble to other actions.

Deliverables

• Implement check of the local package.json before processing bash files. Exit and report any errors if found.