lesshint: newlineAfterBlock with nested blocks

Hello,

if got problems to resolve the following warning(s)

Warning: app.less: line 1636, col 5, newlineAfterBlock: All blocks should be followed by a new line.
Warning: app.less: line 1641, col 3, newlineAfterBlock: All blocks should be followed by a new line.
Warning: app.less: line 1644, col 5, newlineAfterBlock: All blocks should be followed by a new line.
Warning: app.less: line 1649, col 3, newlineAfterBlock: All blocks should be followed by a new line.
Warning: app.less: line 1652, col 5, newlineAfterBlock: All blocks should be followed by a new line.
Warning: app.less: line 1657, col 3, newlineAfterBlock: All blocks should be followed by a new line.
Warning: app.less: line 1660, col 5, newlineAfterBlock: All blocks should be followed by a new line.

It works not on nested blocks for me. Here is my less source: (starting from line 1631)

/* Animations */
[ui-view] {
  &.ng-enter {
    opacity: 0;
    transition: 0.25s linear all;
    &.ng-enter-active {
      opacity: 1;
    }
  }

  &.ng-add {
    opacity: 0;
    transition: 0.25s linear all;
    &.ng-add-active {
      opacity: 1;
    }
  }

  &.ng-leave {
    opacity: 1;
    transition: 0.25s linear all;
    &.ng-leave-active {
      opacity: 0;
    }
  }

  &.ng-remove {
    opacity: 1;
    transition: 0.25s linear all;
    &.ng-remove-active {
      opacity: 0;
    }
  }
}

I found nothing about nested formatting in your documentation, so I tried some cases but always got

newlineAfterBlock: All blocks should be followed by a new line.

or

trailingWhitespace: There should't be any trailing whitespace.

How should the less code structured to remove the warning? Or is it a bug?