Bug? – wrong resolution unit conversion in SCSS

It seems like conversion is somehow flipped

dpi-to-dpcm: 0dpcm + 1dpi;  // 2.54dpcm     should be 0.3937dpcm
                                         ⤮  
dpcm-to-dpi: 0dpi + 1dpcm;  // 0.3937dpi    should be 2.54dpi    

... or just uses px, in, cm conversion (missing the "per" part)

in-to-cm: 0cm + 1in;   // 2.54cm; 
cm-to-in: 0in + 1cm;   // 0.3937in

Functions to "fix" the problem

@function dpi($input)  { @return convert-resolution-unit($input, dpi); }
@function dpcm($input) { @return convert-resolution-unit($input, dpcm); }
@function dppx($input) { @return convert-resolution-unit($input, dppx); }

@function strip-unit($input) { @return $input/($input * 0 + 1); }
@function convert-resolution-unit($input, $to-unit) {
    $units: (dppx: 0dppx, dpcm: 0dpcm, dpi: 0dpi);
    $input-unit: map-get($units, unit($input));
    $to-unit: map-get($units, $to-unit);
    @return $to-unit + if(1dppx < 95dpi, 
         strip-unit($input-unit + (strip-unit($input) + $to-unit)), 
         $input
    );
}



test { 
    dpi-to-dpi : dpi(1dpi);    //  1dpi;
    dpcm-to-dpi: dpi(1dpcm);   //  2.54dpi;
    dppx-to-dpi: dpi(1dppx);   //  96dpi;

    dpi-to-dpcm : dpcm(1dpi);  //  0.3937dpcm
    dpcm-to-dpcm: dpcm(1dpcm); //  1dpcm
    dppx-to-dpcm: dpcm(1dppx); //  37.79528dpcm

    dpi-to-dppx : dppx(1dpi);  //  0.01042dppx
    dpcm-to-dppx: dppx(1dpcm); //  0.02646dppx
    dppx-to-dppx: dppx(1dppx); //  1dppx
}