This fixes problems with the markdownify logic for indentation inside
list items.
This PR uses a branch building on that for #120, #150 and #151, so
those three PRs should be merged first before merging this one.
There is limited logic in markdownify for handling indentation in the
case of nested lists. There are two major problems with this logic:
* As it's in `convert_list`, causing a list to be indented when inside
another list, it does not add indentation for any other elements
such as paragraphs that may be found inside list items (or `<pre>`,
`<blockquote>`, etc.), so such elements are wrongly not indented and
terminate the list in the output.
* It uses fixed indentation of one tab. Following CommonMark, a tab
in Markdown is considered equivalent to four spaces, which is not
sufficient indentation in ordered list items with a number of three
or more digits.
Fix both of these issues by making `convert_li` handle indentation for
the contents of `<li>`, based on the length of the list item marker,
rather than doing it in `convert_list` at all.
There are various cases in which inline text fails to be separated by
(sufficiently many) newlines from adjacent block content. A paragraph
needs a blank line (two newlines) separating it from prior text, as
does an underlined header; an ATX header needs a single newline
separating it from prior text. A list needs at least one newline
separating it from prior text, but in general two newlines (for an
ordered list starting other than at 1, which will only be recognized
given a blank line before).
To avoid accumulation of more newlines than necessary, take care when
concatenating the results of converting consecutive tags to remove
redundant newlines (keeping the greater of the number ending the prior
text and the number starting the subsequent text).
This is thus an alternative to #108 that tries to avoid the excess
newline accumulation that was a concern there, as well as fixing more
cases than just paragraphs, and updating tests.
Fixes#92Fixes#98
