Footnotes are squished together by rustdoc when there's no empty line between them

[CJKay]

Problem

Footnote lines, when written on adjacent lines, squish into a single footnote:

//! [^1]: Footnote A.
//! [^2]: Footnote B.
//! [^3]: Footnote C.

Steps

1. Copy-paste the following snippet at the top of a new module:

   //! Reference to footnotes A[^1], B[^2] and C[^3].
   //!
   //! [^1]: Footnote A.
   //! [^2]: Footnote B.
   //! [^3]: Footnote C.
   

2. Run cargo doc.

3. Observe that the footnotes have been incorrectly rendered as a single footnote.

Possible Solution(s)

No response

Notes

One workaround is to separate the footnotes with empty lines:

//! [^1]: Footnote A.
//! 
//! [^2]: Footnote B.
//! 
//! [^3]: Footnote C.

It's not pretty, though.

Version

cargo 1.64.0-nightly (b1dd22e66 2022-07-09)
release: 1.64.0-nightly
commit-hash: b1dd22e668af5279e13a071ad4b17435bd6bfa4c
commit-date: 2022-07-09
host: x86_64-apple-darwin
libgit2: 1.4.2 (sys:0.14.2 vendored)
libcurl: 7.79.1 (sys:0.4.55+curl-7.83.1 system ssl:(SecureTransport) LibreSSL/3.3.6)
os: Mac OS 12.5.0 [64-bit]

[Eh2406]

Transferring to Rust as it is an issue with doc generation.

[ehuss]

I think this is somewhat working as intended. Footnote definitions need to be separated by blank lines.

That is not ideal, and I think pulldown-cmark/pulldown-cmark#20 is the closest thing tracking this issue.

[GuillaumeGomez]

This is the expected behaviour from commonmark as you can see here.

Closing then.

[CJKay]

This is the expected behaviour from commonmark as you can see here.

Closing then.

Hi @GuillaumeGomez, CommonMark does not support footnotes at all. RustDoc is very explicit that it does, so the behaviour of RustDoc's footnotes should probably be based on whatever library it uses for Markdown parsing rather than actual CommonMark.

You can see from this simple example that CommonMark does not support footnotes:

Reference to footnote A[^1].

[^1]: Footnote A.

<p>Reference to footnote A[^1].</p>
<p>[^1]: Footnote A.</p>

But CommonMark with "extensions" does:

<p>Hello, World<a href="#fn1" class="footnote-ref" id="fnref1"
role="doc-noteref"><sup>1</sup></a>!</p>
<section id="footnotes" class="footnotes footnotes-end-of-document"
role="doc-endnotes">
<hr />
<ol>
<li id="fn1"><p>The world is big!<a href="#fnref1" class="footnote-back"
role="doc-backlink">↩︎</a></p></li>
</ol>
</section>

[GuillaumeGomez]

Oh I see, my apologies. Reopening the issue then.

[fmease]

Triage: Still an issue.

[GuillaumeGomez]

Taking a look.