tidy borked my rules (recent pull changed behavior)

[iWantToKeepAnon]

Prerequisites

• [ X ] I am running the latest version
• [ X ] I checked the documentation and found no answer
• [ X ] I checked to make sure that this issue has not already been filed

Expected Behavior

Rule on gocomics returns og:image in an <img/> element.

Current Behavior

Empty output. Seems like tidy drops the whole pile of HTML on the floor (i.e. it returns the empty string) but doesn't trigger an exception.

Steps to Reproduce

Make sure tidy is installed in php and function 'tidy_parse_string' is available.

Run url: https://www.gocomics.com/calvinandhobbes/2020/01/06

Against rule:

{
    "type": "xpath",
    "xpath": "meta['og:image' = @property]\/@content",
    "start_element": "<img title='gocomics' src='",
    "end_element": "' \/>"
}

Failure Information (for bugs)

I recently did a fresh pull. This seems to be the culprit : https://github.com/feediron/ttrss_plugin-feediron/commit/7e538de5a7ccffda986f8af3fa33a29b7cecbda5#diff-e9fa0d13b445ed0246ee0003db4374d6

• Set tidy-source true by default

Why is a default behavior change a good idea? I added "tidy-source": false to all my rules and the above works again. I have a few rules and adding that to each was a bit of a pain, but I am functional again.

Seems like a bad idea to me!

• Operating System: linux (centos) and windows (10)
• TTRSS version/git version: always on a fresh master pull
• PHP version: v7.1
• Feediron Configuration: (see above)

Paste Configuration here (see above)

[dugite-code]

The reason tidy was made default was along the same lines as why firefox automatically fixes broken web pages, I was encountering too many issues with broken websites that were easily solved with a quick tidy.

I'm not going to revert the change, however what I'll do is introduce several global switches (like the debug:true) switch so you can change the default behavior

[iWantToKeepAnon]

I'm not so concerned about the switch as I am that tidy failed and returned a zero length string. Perhaps a small size check and if tidy fails (without throwing an exception), then keep the original html string. (?)

[dugite-code]

I've added a check to catch if tidy removes more than half of the html. I still need to fix the defaults before I merge to master

[iWantToKeepAnon]

Perfect, thanks for a quick turn around! : ))