Feature request: Expose line number index for color highlighting

[Apostolique]

Feature request

What problem does this feature solve?

It makes it possible to start the lines numbers to something else than 1.

What does the proposed API look like?

Exposed in a similar way to the current line highlighting in the markdown.

How should this be implemented in your opinion?

saber/packages/saber/src/markdown/highlight-plugin.js

Line 66 in ec2cbac

const lineNumber = index + 1

Are you willing to work on this yourself?

I could if no one else does.

[egoist]

We are using CSS counters in saber-highlight-css:

saber/packages/saber-highlight-css/default.css

Line 74 in ec2cbac

counter-reset: linenumber;

So probably we should inline that style into this line instead:

saber/packages/saber/src/markdown/highlight-plugin.js

Line 14 in ec2cbac

'<span aria-hidden="true" class="saber-highlight-line-numbers">' +

Like this:

<span 
  aria-hidden="true" 
  class="saber-highlight-line-numbers" 
  style="counter-reset: linenumber 0">

And make that 0 customizable.