Markdown: store if list is loose or not in the List

[KristofferC]

Punt on updating the renders in base but do it for the Documenter HTML renderer: JuliaDocs/Documenter.jl#685

[mortenpi]

Lists with multiple child blocks don't get the loose flag at the moment:

julia> Markdown.md"""
       - a
       - b

         a
       - c
       """.content
1-element Array{Any,1}:
 Markdown.List(Any[Any[Markdown.Paragraph(Any["a"])], Any[Markdown.Paragraph(Any["b"]), Markdown.Paragraph(Any["a"])], Any[Markdown.Paragraph(Any["c"])]], -1, false)

Is there anything specific holding back updating the print/show methods in Base to using the .loose flag? (I haven't looked at the code myself.)

Would you consider it a fix for #21922? Also, just for reference, #22071.

I think this is a good way to get the tight/loose lists in. Having Paragraphs wrapped around list items is actually consistent with the AST from the CommonMark sample parser. It's then up to the renderer to display the paragraphs differently based on whether the list is loose or not (as you've done in Documenter).

[KristofferC]

Nothing preventing updating Base render methods but there is a need to thread a parent through every render call (like is done in Documenter) and getting Documenter output the correct HTML seems like the most important thing. I will fix and add a test for the bug you mentioned.

The next thing to fix is probably the terminal renderer.

[KristofferC]

Ooooooh, these two constructors below now create the List with the loose containing uninitialized memory. #24943 strikes again

[KristofferC]

Looks like the mac builder is trying to build gcc, presumably because some network error.