Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.3.14)
// Compass (v1.0.3)
// ----

.message-box{
  .fuga{
    .jast-hoge-hoge &
    {
      color :red;
    }
  }
}

.message-box{
  &.error{
    color :red;
  }
  & .child-error{
    color :red;
  }
}

SassMeister-output.css

.jast-hoge-hoge .message-box .fuga {
  color: red;
}

.message-box.error {
  color: red;
}
.message-box .child-error {
  color: red;
}