[csswg-drafts] [css-values] Specify how to handle negative percentage basis in mathematical expressions (#6298)

johannesodland has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-values] Specify how to handle negative percentage basis in mathematical expressions ==
Some properties like object-position can have a negative percentage basis. 

This causes an issue where some browsers calculates/simplifies `clamp(100%, 50%, 0%)` to 100% ignoring the negative percentage basis, but solves `clamp(100%, 50% + 0px, 0%)` to 50%. With a percentage basis of `-100px` the original equation is equal to `clamp(-100px, -50px, 0px)` which would solve to -50px. Solving the equation without accounting for the negative basis creates unexpected behaviour.

(See https://bugzilla.mozilla.org/show_bug.cgi?id=1709018). 

It would be helpful if the spec specified how to handle negative percentage basis in mathematical expressions https://drafts.csswg.org/css-values-4/#calc-func




Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/6298 using your GitHub account


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Received on Wednesday, 19 May 2021 18:21:51 UTC