Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.4.0.rc.1)
// Compass (v1.0.0.alpha.20)
// ----

$wrapper: ".thing";

@mixin when-drawer-is-open {
  @at-root #{selector-replace(&,
  "#{$wrapper}",
  "#{$wrapper}[data-drawer=\"open\"]")} {
    @content
  }
}

#{$wrapper} {
  &.thing-1 {
    color: red;
  
    @include when-drawer-is-open {
      color: blue;
    }  
  }
}

#{$wrapper} {
  .thing-2 {
    color: red;
  
    @include when-drawer-is-open {
      color: blue;
    }  
  }
}

SassMeister-output.css

.thing.thing-1 {
  color: red;
}
.thing-1.thing[data-drawer="open"] {
  color: blue;
}

.thing .thing-2 {
  color: red;
}
.thing[data-drawer="open"] .thing-2 {
  color: blue;
}