`nf-core schema build` changes default value from `null` to `"None"`

[Midnighter]

Description of the bug

Title mostly says it. I have a defined schema with a parameter that has "default": null. When I run nf-core schema build this default gets replaced with "None" which looks like it comes from Python.

My nextflow.config has the following entry which probably confuses the logic in the nf-core tool leading to the above result.

params {
    notify_slack = true
    slack_hook_info = params.notify_slack ? "$SLACK_HOOK_INFO" : null
}

The environment variable SLACK_HOOK_INFO is not defined when I run this.

Command used and terminal output

nf-core schema build

System information

• Linux 5.17.5-76051705-generic
• nf-core, version 2.5.1
• Python 3.9.5