# GitLab Markdown

This document is intended to be a comprehensive example of custom GitLab
Markdown usage. It will be parsed and then tested for accuracy. Let's get
started.

## Markdown

GitLab uses [Redcarpet](http://git.io/ld_NVQ) to parse all Markdown into
HTML.

It has some special features. Let's try 'em out!

### No Intra Emphasis

This string should have no emphasis: foo_bar_baz

### Tables

| Header   | Row  | Example |
| :------: | ---: | :------ |
| Foo      | Bar  | **Baz** |

### Fenced Code Blocks

```c
#include<stdio.h>

main()
{
    printf("Hello World");

}
```

```python
print "Hello, World!"
```

### Strikethrough

This text says this, ~~and this text doesn't~~.

### Superscript

This is my 1^(st) time using superscript in Markdown. Now this is my
2^(nd).

### Next step

After the Markdown has been turned into HTML, it gets passed through...

## HTML::Pipeline

### SanitizationFilter

GitLab uses <a href="http://git.io/vfW8a" class="sanitize" id="sanitize-link">HTML::Pipeline::SanitizationFilter</a>
to sanitize the generated HTML, stripping dangerous or unwanted tags.

Its default whitelist is pretty permissive. Check it:

<b id="manual-b">This text is bold</b> and <em id="manual-em">this text is emphasized</em>.

<code id="manual-code">echo "Hello, world!"</code>

Press <kbd>s</kbd> to search.

<strike>Emoji</strike> Plain old images! <img
src="http://www.emoji-cheat-sheet.com/graphics/emojis/smile.png" width="20"
height="20" id="manual-img" />

Here comes a line break:

<br id="manual-br" />

And a horizontal rule:

<hr id="manual-hr" />

As permissive as it is, we've allowed even more stuff:

<span class="light" id="span-class-light">Span elements</span>

<a href="#" rel="nofollow" id="a-rel-nofollow">This is a link with a defined rel attribute, which should be removed</a>

<a href="javascript:alert('Hi')" id="a-href-javascript">This is a link trying to be sneaky. It gets its link removed entirely.</a>

### Escaping

The problem with SanitizationFilter is that it can be too aggressive.

| Input       | Expected         | Actual    |
| ----------- | ---------------- | --------- |
| `1 < 3 & 5` | 1 &lt; 3 &amp; 5 | 1 < 3 & 5 |
| `<foo>`     | &lt;foo&gt;      | <foo>     |

### EmojiFilter

Because life would be :zzz: without Emoji, right? :rocket:

Get ready for the Emoji :bomb:: :+1::-1::ok_hand::wave::v::raised_hand::muscle:

### TableOfContentsFilter

All headers in this document should be linkable. Try it.

### AutolinkFilter

These are all plain text that should get turned into links:

- http://about.gitlab.com/
- https://google.com/
- ftp://ftp.us.debian.org/debian/
- smb://foo/bar/baz
- irc://irc.freenode.net/git
- http://localhost:3000

But it shouldn't autolink text inside certain tags:

- <code id="autolink-code">http://about.gitlab.com/</code>
- <a id="autolink-a">http://about.gitlab.com/</a>
- <kbd id="autolink-kbd">http://about.gitlab.com/</kbd>

### Reference Filters (e.g., #<%= issue.iid %>)

References should be parseable even inside _!<%= merge_request.iid %>_ emphasis.

#### UserReferenceFilter

- All: @all
- User: @<%= user.username %>
- Group: @<%= group.name %>
- Ignores invalid: @fake_user
- Ignored in code: `@<%= user.username %>`
- Ignored in links: [Link to @<%= user.username %>](#user-link)

#### IssueReferenceFilter

- Issue: #<%= issue.iid %>
- Issue in another project: <%= xref %>#<%= xissue.iid %>
- Ignored in code: `#<%= issue.iid %>`
- Ignored in links: [Link to #<%= issue.iid %>](#issue-link)

#### MergeRequestReferenceFilter

- Merge request: !<%= merge_request.iid %>
- Merge request in another project: <%= xref %>!<%= xmerge_request.iid %>
- Ignored in code: `!<%= merge_request.iid %>`
- Ignored in links: [Link to !<%= merge_request.iid %>](#merge-request-link)

#### SnippetReferenceFilter

- Snippet: $<%= snippet.id %>
- Snippet in another project: <%= xref %>$<%= xsnippet.id %>
- Ignored in code: `$<%= snippet.id %>`
- Ignored in links: [Link to $<%= snippet.id %>](#snippet-link)

#### CommitRangeReferenceFilter

- Range: <%= commit_range %>
- Range in another project: <%= xref %>@<%= xcommit_range %>
- Ignored in code: `<%= commit_range %>`
- Ignored in links: [Link to <%= commit_range %>](#commit-range-link)

#### CommitReferenceFilter

- Commit: <%= commit.id %>
- Commit in another project: <%= xref %>@<%= xcommit.id %>
- Ignored in code: `<%= commit.id %>`
- Ignored in links: [Link to <%= commit.id %>](#commit-link)

#### LabelReferenceFilter

- Label by ID: ~<%= simple_label.id %>
- Label by name: ~<%= simple_label.name %>
- Label by name in quotes: ~"<%= label.name %>"
- Ignored in code: `~<%= simple_label.name %>`
- Ignored in links: [Link to ~<%= simple_label.id %>](#label-link)