Inserting media with multiple newlines in caption breaks HTML

[jonieske]

Steps to reproduce:

1. Open add media dialog in editor to insert image
2. Select image, enter caption with multiple newlines, eg:

"one
two
three"

3. Leave alt text field empty
4. Insert image into post
5. Save/Update

As a result, HTML code breaks and image isn't displayed. This happens because caption is inserted to alt attribute in case it's empty, and newlines break the markup. Toggling between text and visual modes before initial post save fixes the code though.

Proposed fix:
Remove newlines from content that is automatically inserted to alt attribute.

[kovshenin]

I can reproduce this against trunk. Here's the HTML code that gets generated when inserting the image with a multi-line caption and no alt tag: ​http://cl.ly/image/3c0d253C3O3a

[kovshenin]

Replace newlines with spaces before sending to the editor

[SergeyBiryukov]

Confirmed. Appears to be a regression. In 3.4.2, an empty alt attribute wasn't populated with caption.

[azaozz]

Replying to SergeyBiryukov:

Confirmed too. Perhaps the regex should be:

props.alt.replace( /[\r\n]+/g, ' ' );

so we replace multiple new lines with one space.

[kovshenin]

Replying to azaozz: sounds fair :)

[kovshenin]

Replace multiple new lines with one space.

[azaozz]

In 23298:

Media: when copying from "caption" (textarea) to "alt" (text input) also remove line breaks, props kovshenin, fixes #23176 for trunk

[azaozz]

In 23299:

Media: when copying from "caption" (textarea) to "alt" (text input) also remove line breaks, props kovshenin, fixes #23176 for 3.5