Fix to prefer flow over definitions, setext headings

An undocumented part of CommonMark is how to deal with things in definition
labels or definition titles (which both can span multiple lines).
Can flow (or containers?) interrupt them?
They can according to the `cmark` reference parser, so this was implemented here.

This adds a new `Content` content type, which houses zero or more definitions,
and then zero-or-one paragraphs.
Content can be followed by a setext heading underline, which either turns
into a setext heading when the content ends in a paragraph, or turns into
the start of the following paragraph when it is followed by content that
starts with a paragraph, or turns into a stray paragraph.

1 files changed, 5 insertions, 2 deletions

diff --git a/src/construct/list_item.rs b/src/construct/list_item.rs
index 658c2c7..13b740b 100644
--- a/src/construct/list_item.rs
+++ b/src/construct/list_item.rs
@@ -62,13 +62,14 @@ use crate::construct::partial_space_or_tab::space_or_tab_min_max;
 use crate::event::{Kind, Name};
 use crate::resolve::Name as ResolveName;
 use crate::state::{Name as StateName, State};
+use crate::subtokenize::Subresult;
 use crate::tokenizer::Tokenizer;
 use crate::util::{
     constant::{LIST_ITEM_VALUE_SIZE_MAX, TAB_SIZE},
     skip,
     slice::{Position, Slice},
 };
-use alloc::{vec, vec::Vec};
+use alloc::{string::String, vec, vec::Vec};
 
 /// Start of list item.
 ///
@@ -370,7 +371,7 @@ pub fn cont_filled(tokenizer: &mut Tokenizer) -> State {
 }
 
 /// Find adjacent list items with the same marker.
-pub fn resolve(tokenizer: &mut Tokenizer) {
+pub fn resolve(tokenizer: &mut Tokenizer) -> Result<Option<Subresult>, String> {
     let mut lists_wip: Vec<(u8, usize, usize, usize)> = vec![];
     let mut lists: Vec<(u8, usize, usize, usize)> = vec![];
     let mut index = 0;
@@ -472,4 +473,6 @@ pub fn resolve(tokenizer: &mut Tokenizer) {
 
         index += 1;
     }
+
+    Ok(None)
 }