Compassのsprite-mapでハマった ref: http://qiita.com/cancer/items/4c0d8f577c71e4b8667e

file0.txt

$sprite-map: sprite-map("sprite/*.png");

%sprite-base{
    $sprite-path: sprite-path($sprite-map);
    $sprite-width: image-width("sprite/"#{$sprite-path}) / 2;
    $sprite-height: image-height("sprite/"#{$sprite-path}) / 2;

    background-image: sprite-url($sprite-map);
    background-size: $sprite-width $sprite-height;
    background-repeat: no-repeat;
}

file1.txt

Errno::ENOENT on line 28 of /Library/Ruby/Gems/1.8/gems/compass-0.12.2/lib/compass/sass_extensions/functions/image_size.rb: No such file or directory - ...

file2.txt

$sprite-map: sprite-map("sprite/*.png");

%sprite-base{
    background: $sprite-map;

    $sprite-path: sprite-path($sprite-map);

    $sprite-width: image-width("sprite/"#{$sprite-path}) / 2;
    $sprite-height: image-height("sprite/"#{$sprite-path}) / 2;

    background-size: $sprite-width $sprite-height;

file3.txt

$sprite-map: sprite-map("sprite/*.png");
$sprite-url: sprite-url($sprite-map);

%sprite-base{
    $sprite-path: sprite-path($sprite-map);
    $sprite-width: image-width("sprite/"#{$sprite-path}) / 2;
    $sprite-height: image-height("sprite/"#{$sprite-path}) / 2;

    background-image: $sprite-url;
    background-size: $sprite-width $sprite-height;
    background-repeat: no-repeat;