# frozen_string_literal: true module SyntaxSuggest # Keeps track of what elements are in the queue in # priority and also ensures that when one element # engulfs/covers/eats another that the larger element # evicts the smaller element class PriorityEngulfQueue def initialize @queue = PriorityQueue.new end def to_a @queue.to_a end def empty? @queue.empty? end def length @queue.length end def peek @queue.peek end def pop @queue.pop end def push(block) prune_engulf(block) @queue << block flush_deleted self end private def flush_deleted while @queue&.peek&.deleted? @queue.pop end end private def prune_engulf(block) # If we're about to pop off the same block, we can skip deleting # things from the frontier this iteration since we'll get it # on the next iteration return if @queue.peek && (block <=> @queue.peek) == 1 if block.starts_at != block.ends_at # A block of size 1 cannot engulf another @queue.to_a.each { |b| if b.starts_at >= block.starts_at && b.ends_at <= block.ends_at b.delete true end } end end end end