can't dump anonymous class for mixin referenced for the first time

[ryrych]

%input-extend is the first class / placeholder that references animate mixin:

%input-extend
  @include animate(background-color, border-color)

  border: 1px dotted transparent
  cursor: pointer
  overflow: hidden
  padding: 4px

@mixin animate($property...)
  @include transition-property($property...)
  @extend %transition-duration
  @extend %transition-timing

which in turn makes use of Compass (0.12.7) transition-property mixin.
Then I get:

Warning. Error encountered while saving cache 3cdc7334308826d2ddff66150ce71a4ea703c30b/_animations.css.sassc: can't dump anonymous class #<Class:0x0000010c22c740>

Related gems:

• 'sass-rails', '~> 4.0.3'
• 'compass-rails', '~> 2.0.0'

[chrisnicola]

I believe this is a duplicate of #242

[robin850]

Yes, @chrisnicola is right, I'm giving it a close, thanks for reporting !