Initial whitespace in href causes validation error

[westonruter]

Bug Description

Given HTML like this:

<p>Powered by <a href=" https://wordpress.org/">WordPress</a></p>

A INVALID_URL_PROTOCOL validation error is raised:

Notice the initial whitespace before the URL in the href attribute. The link works properly in the non-AMP version, and the above markup causes no validation error in the AMP validator.

So it seems the URL needs to be trimmed before checking whether it is valid.

Expected Behaviour

Steps to reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Screenshots

Additional context

• WordPress version:
• Plugin version:
• Gutenberg plugin version (if applicable):
• AMP plugin template mode:
• PHP version:
• OS:
• Browser: [e.g. chrome, safari]
• Device: [e.g. iPhone6]

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Acceptance criteria

Implementation brief

QA testing instructions

Demo

Changelog entry

[kienstra]

Implementation Brief

It looks like trim( $url ) will fix this, but adding test cases for this will also be important.

[kienstra]

Testing Steps

1. Create a new post
2. Add a Custom HTML block with:

<p><a href=" https://foo.com">Leading Space In href</a></p>
<p><a href="https://foo.com ">Trailing Space In href</a></p>

3. Save, and go to the front-end of the AMP URL
4. Expected: there's no validation error

[csossi]

Verified in QA

[kienstra]

Thanks, Claudio!