Improve Markdown Support - blockquotes with special markers parse wrongly

[igormironchik]

Describe the bug

Blockquote with special mark for highlighting (like [!NOTE]) parses wrongly.

Warning

Have a look at emphasis in second paragraph too. You have there issue too.

Screenshots

To Reproduce

Doxygen.zip

Expected behavior

I'd like to see all other stuff from highlighted blockquote parsed and rendered correctly in it.

Version

1.12.0 (3d494140a674a8344c165a559d841166bbf3b80f*)

No LSB modules are available.
Distributor ID: Neon
Description:    KDE neon 6.0
Release:        22.04
Codename:       jammy

I've built Doxygen from sources.

[albert-github]

So you would like to have something like:

(the fact that *`markdown-it (Rust)` measurement done with `markdown_it::plugins::extra`* is not as emphasis text is already mentioned in another issue).

The problem is that the construction is replaced by a \note command and this ends with an empty line ( in this case this is the line with just > in the example).

I see 2 workarounds:

> [!NOTE]
> *This measurement done with test file in [markdown-it (Rust)](https://github.com/markdown-it-rust/markdown-it)*

> [!NOTE]
> *`markdown-it (Rust)` measurement done with `markdown_it::plugins::extra`*

> [!NOTE]
> **Keep in mind that `markdown-it (Rust)` doesn't support all GFM extensions, so it's not honest
> to compare. `md4qt` supports GitHub's autolinks extension, that `markdown-it (Rust)` doesn't, and
> this requires ~500 microseconds, for example...**

note: the extra real empty line and the replacement of the > line with a new > [!NOTE]

and

> [!NOTE]
> *This measurement done with test file in [markdown-it (Rust)](https://github.com/markdown-it-rust/markdown-it)*<br>
> *`markdown-it (Rust)` measurement done with `markdown_it::plugins::extra`*<br>
> **Keep in mind that `markdown-it (Rust)` doesn't support all GFM extensions, so it's not honest
> to compare. `md4qt` supports GitHub's autolinks extension, that `markdown-it (Rust)` doesn't, and
> this requires ~500 microseconds, for example...**

note: the missing "empty lines" and the addition of <br>

Though I still think this is something doxygen should fix.

[albert-github]

I've just pushed a proposed patch, pull request #10903

[albert-github]

Code has been integrated in master on GitHub (please don't close the issue as this will be done at the moment of an official release).

[igormironchik]

I confirm that this issue is solved. But after Note mark you have extra <br> that is not needed. Look at the screenshot. First time there should be one <br> in HTML.

It will be better with one <br> after Note...

[albert-github]

• How did you obtain the 2nd image?

I ran the version with master (2 <br>) and got:

I ran a version with just 1 <br> in the adjusted code and got:

When we compare the 2 images we see that the version with 2 <br> has a lot of space but obeys the fact that there is a separation between the parts of the notes and shows them more as individual parts.
The version with 1 <br> shows the also the different parts but it all look a bit like a running text.

Probably a matter of taste but in my opinion I think the version with 2 <br> is better although less space would be better.

[igormironchik]

Think more complex. 1 <br> should be only after first string with Note, but all other separators should be with 2 <br>. In this case highlighted blockquotes will be delicious.

[albert-github]

In your comment you already wrote:

But after Note mark you have extra
that is not needed.

I unfortunately missed that and indeed I think the output improves when having the 2 <br> layout except for the part after the Note.

[igormironchik]

You will get:

Mmmmmmm.....

[albert-github]

I now had a look in the input file:

> [!NOTE]
>
> *This measurement done with test file in [markdown-it (Rust)](https://github.com/markdown-it-rust/markdown-it)*
>
> *`markdown-it (Rust)` measurement done with `markdown_it::plugins::extra`*
>
> **Keep in mind that `markdown-it (Rust)` doesn't support all GFM extensions, so it's not honest
> to compare. `md4qt` supports GitHub's autolinks extension, that `markdown-it (Rust)` doesn't, and
> this requires ~500 microseconds, for example...**

and here we see an explicit empty line after the > [!NOTE], so I think the 2 <br> is justified here. When we would remove the "empty line" after the > [!NOTE] you will get:

which in my opinion is even nicer.

Still I think 1 <br> after the note would also be nice.