MD027: handle anchor elements correctly

[marquiz]

Description

Fixex false positives of MD027 multiple-spaces-after-blockquote-symbol if quote lines begin with a link, e.g.

> This is a
> [link](link) to somewhere

Related Issues

Types of changes

• [ x Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (non-breaking change that does not add functionality but updates documentation)
• Chore (non-breaking change that does not add functionality or fix an issue)

Checklist:

• I have read the CONTRIBUTING document.
• Wrote good commit messages
• Feature branch is up-to-date with master, if not - rebase it
• Added tests for all new/changed functionality, including tests for positive and negative scenarios
• The PR relates to only one subject with a clear title and description in grammatically correct, complete sentences

[jaymzh]

Nice, thanks!

[jaymzh]

Looks like there's some tests failing @marquiz

[marquiz]

Looks like there's some tests failing @marquiz

Argh, looks like I somehow messed up running tests locally.

In order to fix that I now specified a new doc.extract_as_text function in order to not break MD036 :/ I'm not much of an expert on ruby or this codebase so suggestions how to fix this in nicer way are welcome (tbh, this whole extract_text business looks flaky and fragile and not so well-defined).

I also changed the commit message title (and the title of this PR, accordingly).

[danie1k]

@marquiz & @jaymzh, sadly there is still something broken IMHO.
For example:

raises M027:

> lorem
> -- ipsum

not raises M027:

> lorem
> --ipsum

not raises M027:

> lorem
> - ipsum

In general, it looks like false-positive when there is two or more dashes.

[jaymzh]

That's a different (but related) bug, @danie1k. Can you please file a separate issue?