Crash when processing "font: unset" with level 2 optimizations enabled

[nop00]

CleanCSS crashes when processing "font: unset" with level 2 optimizations enabled.
Note that it does not crash with version 4.0.12 (crashes with versions 4.1.0 and 4.1.1).

Environment

• clean-css version 4.1.1
• node.js version 6.10.3
• operating system: Windows 10

Configuration options

var CleanCSS = require('clean-css');
new CleanCSS({
    level: 2
})

Input CSS

.test {
  font: unset;
}

Output

c:\clean-css-test\node_modules\clean-css\lib\optimizer\level-2\properties\populate-components.js:30
          throw e;
          ^

TypeError: Cannot read property '1' of undefined
    at Object.font [as breakUp] (c:\clean-css-test\node_modules\clean-css\lib\optimizer\level-2\break-up.js:308:66)
    at populateComponents (c:\clean-css-test\node_modules\clean-css\lib\optimizer\level-2\properties\populate-components.js:17:42)
    at optimizeProperties (c:\clean-css-test\node_modules\clean-css\lib\optimizer\level-2\properties\optimize.js:19:3)
    at recursivelyOptimizeProperties (c:\clean-css-test\node_modules\clean-css\lib\optimizer\level-2\optimize.js:63:9)
    at level2Optimize (c:\clean-css-test\node_modules\clean-css\lib\optimizer\level-2\optimize.js:77:3)
    at optimize (c:\clean-css-test\node_modules\clean-css\lib\clean.js:131:5)
    at c:\clean-css-test\node_modules\clean-css\lib\clean.js:104:29
    at c:\clean-css-test\node_modules\clean-css\lib\reader\read-sources.js:26:64
    at loadOriginalSources (c:\clean-css-test\node_modules\clean-css\lib\reader\load-original-sources.js:26:5)
    at c:\clean-css-test\node_modules\clean-css\lib\reader\read-sources.js:26:14

[jakubpawlowicz]

I can see it too - please use { level: { 2: { skipProperties: ['font'] } } } until 4.1.2.

[nop00]

Thanks for the workaround !

[jakubpawlowicz]

The fix is out in 4.1.2.

[nop00]

Thanks!