Expose Document's source and source_lines properties

[abelsromero]

Thank you for opening a pull request and contributing to AsciidoctorJ!

Please take a bit of time giving some details about your pull request:

Kind of change

• [ ] Bug fix
• [x] New non-breaking feature
• [ ] New breaking feature
• [ ] Documentation update
• [ ] Build improvement

Description

What is the goal of this pull request? Expose Document's source and source_lines properties. This is required to be able to use other asciidoctor components like asciidoctor-reducer.

How does it achieve that? Using already present AsciidoctorJ APIs and practices, nothing special.

Are there any alternative ways to implement this? Not that I know.

Are there any implications of this pull request? Anything a user must know? No

Issue

If this PR fixes an open issue, please add a line of the form:

Fixes #1143

Release notes

Please add a corresponding entry to the file CHANGELOG.adoc

[abelsromero]

Btw, I assume this is fine going to 3.0.0? Or a 2.5.8 is planned? No issue at all backporting it if necessary.

[robertpanzer]

Yes, main would be 3.0.0. We can also do a 2.5.8, that contains this change.

[abelsromero]

We can also do a 2.5.8, that contains this change.

If people do not ask for it, I would not do it.

[abelsromero]

Changes done, anything else needs improving? :eyes:

[robertpanzer]

Thank you! Looks good!