Spaces around info string?

[z0al]

The spec says:

The line with the opening code fence may optionally contain some text following the code fence; this is trimmed of leading and trailing spaces and called the info string.

I wonder what spaces actually means to in this context? spaces only? spaces and tabs?

I usually check my assumptions using GitHub Markdown API, but this time I got strange output!

Output:

<pre lang="hey"><code>print 'Hello world!'
</code></pre>

Input:

```·→hey
print 'Hello world!'
```

May someone explain what just happened?

---

NOTE
· represents space
→ represents tab

[kivikakk]

We use an option called CMARK_OPT_GITHUB_PRE_LANG in this fork to output code blocks in a style that github.com expects:

/~https://github.com/github/cmark/blob/07fe00f38e78846bc0760cb02a3b1441dffc9b6d/src/html.c#L186-L192

That aside, though, you're right that the spec is inconsistent; it says "trimmed of leading and trailing spaces" but the code calls cmark_strbuf_trim:

/~https://github.com/github/cmark/blob/07fe00f38e78846bc0760cb02a3b1441dffc9b6d/src/blocks.c#L312-L316

which trims anything matching cmark_isspace. I'll open a PR to the spec upstream to have this changed to "trimmed of leading and trailing whitespace" such that the code is correct.

[kivikakk]

▶️ commonmark/commonmark-spec#505

[z0al]

@kivikakk Thanks

Well, another space-related thing is this:
/~https://github.com/github/cmark/blob/07fe00f38e78846bc0760cb02a3b1441dffc9b6d/test/spec.txt#L542-L546
I think that "each followed optionally by any number of spaces" part isn't accurate, because AFAIK the source code actually accepts both spaces and tabs (I don't understand how re2c works, though 😄 )
/~https://github.com/github/cmark/blob/07fe00f38e78846bc0760cb02a3b1441dffc9b6d/src/scanners.re#L274-L278

P.S: should I open issues like this one in the original cmark repo?

[kivikakk]

You're right, this should say "spaces or tabs" specifically, not "spaces" (which is only U+0020 SPACE) nor "whitespace" (which would also newlines and other kinds of tabs/feeds). I'll add this to my PR at commonmark/commonmark-spec#505.

I think you definitely could open these on the upstream cmark repo, or directly on the CommonMark repo itself like I'm doing if you wanted to call it out as a problem with the spec.

[kivikakk]

commonmark/commonmark-spec#505 got merged, so these issues are hopefully fixed 👍