wrong output with calc()

[liuwf2012]

initial state

.class {
  width: calc(-25rem - (1280px - 100vw) * 0.5);
}

correct minimization

.class{
  width: calc(-25rem - 640px + 50vw);
}

actual minimization

.class{
  width: calc(-25rem - 640px - 50vw);
}

[alexander-akait]

Bug in postcss calc

[cduivis]

I just encountered the same issue:

initial code:
calc(0.7 * 560 * (1220px - 100vw) / 1220 + 0.1 * 560 * (1220px - 50vw) / 1220)
resulting code:
calc(478240px - 39200vw + 68320px - 2800vw)

I see this bug was already reported in 2019 is some actually picking this up?

Btw for such complex behavior as redefining calculations, it would be a good thing to define some unit tests as this is easily broken.

[wszydlak]

Bug in postcss calc

@alexander-akait Could you provide issue number in postcss-calc? Is this already fixed?

[ludofischer]

@alexander-akait Could you provide issue number in postcss-calc? Is this already fixed?

It's likely this one: postcss/postcss-calc#137 edit: actually wrong issue, the referenced issue is a crash, this one outputs the wrong value.

[ludofischer]

Fixed in cssnano 5.0.15.

calc(0.7 * 560 * (1220px - 100vw) / 1220 + 0.1 * 560 * (1220px - 50vw) / 1220)

now returns

calc(448px - 34.42623vw)