Saving node description property to the library

[kazuhitoyokoi]

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Proposed changes

To reuse node description in function node via the library, I added the function which saves the node description with other metadata and JavaScript code in a function node.

Checklist

• I have read the contribution guidelines
• For non-bugfix PRs, I have discussed this change on the forum/slack team.
• I have run grunt to verify the unit tests pass
• I have added suitable unit tests to cover the new/changed functionality

[coveralls]

Coverage increased (+0.06%) to 77.504% when pulling 08ef9ee on kazuhitoyokoi:dev-addinfo2lib into c9ad5be on node-red:dev.

[knolleary]

Thanks @kazuhitoyokoi

To summarise, this fix works by replacing any newline character, \n with the literal string "\n" when saving to the library. And when loading from the library, replacing any literal string "\n" with the newline character.

This does introduce an edge case where a node's info contains the string \n already. For example:

This node saves the data to c:\node-red\new-data.csv

When restored from the library, it would appear as:

This node saves the data to c:
ode-red
ew-data.csv

Can we add an extra step to replace "\n" with "\\n" before we replace \n with "\n"?

[kazuhitoyokoi]

@knolleary Thank you for the information. I did not care about backslash characters. I modified code to add the handling for backslash.