Incorrect border transform makes border disappear

[mashedcode]

Environment

clean-css version 4.2.1 (clean-css-cli -O2 from master)

Input CSS

.test {
        border-color: currentcolor currentcolor rgb(148, 148, 148);
        border-image: none 100% / 1 / 0 stretch;
        border-width: 0px 0px 1px;
        border-style: none none solid;
}

Actual output CSS

.test{border-image:none 100%/1/0 stretch;border:0 currentcolor}

Expected output CSS

.test{border-color:#949494;border-width:0 0 1px;border-style:solid}

or

.test{border:0;border-bottom:1px solid #949494}

[jakubpawlowicz]

Thank you for flagging this issue - see 3e82bdc#diff-eaef0d9fa6e206ff3078d62db24fc3da7909fde09a53728f592d5a0575df7793R74 for valid test cases.

By the way I didn't find border-image:none 100%/1/0 stretch to be invalid but clean-css doesn't touch border-image at all. Would you care to elaborate, maybe there's room for further improvement.

[mashedcode]

Thanks!
The original css was generated by servo.
I guess the best optimization for border-image in this case would be border-image:0 because all provided values are the default values.
Definitely not a very common property.
Yes, keeping it as is would be correct.

[jakubpawlowicz]

Thanks @mashedcode - I've just opened #1138 for border-image improvements.