Make attributes visible in c-tips chapter

[austinglaser]

Fixes #211

[rust-highfive]

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[andre-richter]

In my browser (Firefox) they are rendered:

[adamgreig]

I also see them render OK in Chrome; what browser are you using @austinglaser ?

[austinglaser]

Firefox 70.0.1, on ubuntu. I don't have any custom styles enabled.

If you build from my branch, does the chapter mis-render on your browsers?

[andre-richter]

Firefox 70.0.1, on ubuntu. I don't have any custom styles enabled.

If you build from my branch, does the chapter mis-render on your browsers?

Same browser here, to the last digit. Ubuntu 64bit.

[austinglaser]

If I look at the page source for one of the offending examples, I see:

<pre><pre class="playpen"><code class="language-rust">
<span class="boring">#![allow(unused_variables)]
fn main() {
</span>/// In your top-level lib.rs

<span class="boring">[cfg(feature=&quot;FIR&quot;)]
</span>pub mod fir;

<span class="boring">[cfg(feature=&quot;IIR&quot;)]
</span>pub mod iir;
<span class="boring">}
</code></pre></pre>

What do you see there on your system?

[austinglaser]

I see the same behavior (and the same static html, including boring spans) when building master locally with mdbook v0.3.4. Do I need to provide any additional arguments/configuration to mdbook other than mdbook serve in the root directory?

I've tried explicitly clearing my browser's cache, and I see the same page.

I'm looking at https://rust-embedded.github.io/book/c-tips/index.html. Is there another hosting location for the book that could cause this confusion?

Are there other things I could check? Does mdbook use rustdoc internally -- could that be a source of version mismatches? The rendering you're seeing seems like it's likely to come from a newer version of the tool which is smarter about attributes -- but the fact that I see this on the public site would seem to indicate that it's unlikely to be solely an issue with tooling versions on my system.

[adamgreig]

Ah, I'm looking at https://docs.rust-embedded.org/book/c-tips/index.html which renders OK, whereas your link to rust-embedded.github.io does not render correctly (with the attributes missing).

docs.rust-embedded.org is a CNAME for rust-embedded.github.io though, so it's not immediately clear to me why they're different...

[austinglaser]

There it is! Your link renders fine for me as well.

That probably means we should hold off on merging this until verifying that the changes render correctly when they eventually get pushed to the rust-embedded.org site.

Also, I've found a couple other places in the book where attributes are mistakenly getting swallowed -- I'll add them to this PR as well.

[adamgreig]

This repository is configured to serve this repository's gh-pages branch at the rust-embedded.github.io link, and the gh-pages clearly has the boring spans: https://github.com/rust-embedded/book/blob/gh-pages/c-tips/index.html

Meanwhile the docs repository's gh-pages branch is hosted at docs.rust-embedded.org and also has CI build this repository, which does not have the boring tags: https://github.com/rust-embedded/docs/blob/gh-pages/book/c-tips/index.html

I suspect the problem is that docs uses mdbook 0.2.1:

https://github.com/rust-embedded/docs/blob/master/ci/install.sh

while book uses latest:

https://github.com/rust-embedded/book/blob/master/ci/install.sh

Edit: in fact it looks like I made the commit that stuck docs on 0.2.1, and the fix for book never made it through to docs.

So it looks like we should have docs start using latest mdbook, and we need to fix all the attributes in book (and perhaps in discovery) to keep them showing up.

[austinglaser]

I've opened a PR to make the mdbook on docs the same as book. Additionally, I've fixed what I think are all the occurrences of erroneously-swallowed code in examples (at least rg boring book after a build doesn't turn up any offenders)

[austinglaser]

It looks like this is fixed in mdbook v0.3.5: rust-lang/mdBook#1088

[adamgreig]

Thanks for chasing this down, @austinglaser!