Creates a breadcrumb trail leading from the current item to its parent, to
its parent’s parent, etc, until the root item is reached. This function
does not require that each intermediate item exist; for example, if there
is no `/foo/` item, breadcrumbs for a `/foo/bar/` item will contain a `nil`
element.
@return [Array] The breadcrumbs, starting with the root item and ending
with the item itself
def breadcrumbs_trail
trail = []
idx_start = 0
loop do
idx = @item.identifier.index('/', idx_start)
break if idx.nil?
idx_start = idx+1
identifier = @item.identifier[0..idx]
trail << @items[identifier]
end
trail
end