feat: quickfix (#293)

* feat: quickfix (not implemented)

* [WIP]: Wed 09 Dec 2020 11:11:30 PM EST

* somewhat working linked list impl

* getting closer

* might be working

* might be working for real

* works and implemented basic example

* dont forget to close prompt

* fix descending and add more tests

* test fixes

* fix test

* more logging

* Fix some more tests

* Fix logging messing up tests

* fix: lint

* fix: multi select stuffs

lua/telescope/algos/linked_list.lua

@@ -0,0 +1,222 @@
+
+local LinkedList = {}
+LinkedList.__index = LinkedList
+
+function LinkedList:new(opts)
+  opts = opts or {}
+  local track_at = opts.track_at
+
+  return setmetatable({
+    size = 0,
+    head = false,
+    tail = false,
+
+    -- track_at: Track at can track a particular node
+    --              Use to keep a node tracked at a particular index
+    --              This greatly decreases looping for checking values at this location.
+    track_at = track_at,
+    _tracked_node = nil,
+    tracked = nil,
+  }, self)
+end
+
+function LinkedList:_increment()
+  self.size = self.size + 1
+  return self.size
+end
+
+local create_node = function(item)
+  return {
+    item = item
+  }
+end
+
+function LinkedList:append(item)
+  local final_size = self:_increment()
+
+  local node = create_node(item)
+
+  if not self.head then
+    self.head = node
+  end
+
+  if self.tail then
+    self.tail.next = node
+    node.prev = self.tail
+  end
+
+  self.tail = node
+
+  if self.track_at then
+    if final_size == self.track_at then
+      self.tracked = item
+      self._tracked_node = node
+    end
+  end
+end
+
+function LinkedList:prepend(item)
+  local final_size = self:_increment()
+  local node = create_node(item)
+
+  if not self.tail then
+    self.tail = node
+  end
+
+  if self.head then
+    self.head.prev = node
+    node.next = self.head
+  end
+
+  self.head = node
+
+  if self.track_at then
+    if final_size == self.track_at then
+      self._tracked_node = self.tail
+    elseif final_size > self.track_at then
+      self._tracked_node = self._tracked_node.prev
+    else
+      return
+    end
+
+    self.tracked = self._tracked_node.item
+  end
+end
+
+-- [a, b, c]
+--  b.prev = a
+--  b.next = c
+--
+--  a.next = b
+--  c.prev = c
+--
+-- insert d after b
+-- [a, b, d, c]
+--
+--  b.next = d
+--  b.prev = a
+--
+-- Place "item" after "node" (which is at index `index`)
+function LinkedList:place_after(index, node, item)
+  local new_node = create_node(item)
+
+  assert(node.prev ~= node)
+  assert(node.next ~= node)
+  local final_size = self:_increment()
+
+  -- Update tail to be the next node.
+  if self.tail == node then
+    self.tail = new_node
+  end
+
+  new_node.prev = node
+  new_node.next = node.next
+
+  node.next = new_node
+
+  if new_node.prev then
+    new_node.prev.next = new_node
+  end
+
+  if new_node.next then
+    new_node.next.prev = new_node
+  end
+
+
+  if self.track_at then
+    if index == self.track_at then
+      self._tracked_node = new_node
+    elseif index < self.track_at then
+      if final_size == self.track_at then
+        self._tracked_node = self.tail
+      elseif final_size > self.track_at then
+        self._tracked_node = self._tracked_node.prev
+      else
+        return
+      end
+    end
+
+    self.tracked = self._tracked_node.item
+  end
+end
+
+function LinkedList:place_before(index, node, item)
+  local new_node = create_node(item)
+
+  assert(node.prev ~= node)
+  assert(node.next ~= node)
+  local final_size = self:_increment()
+
+  -- Update head to be the node we are inserting.
+  if self.head == node then
+    self.head = new_node
+  end
+
+  new_node.prev = node.prev
+  new_node.next = node
+
+  node.prev = new_node
+  -- node.next = node.next
+
+  if new_node.prev then
+    new_node.prev.next = new_node
+  end
+
+  if new_node.next then
+    new_node.next.prev = new_node
+  end
+
+
+  if self.track_at then
+    if index == self.track_at - 1 then
+      self._tracked_node = node
+    elseif index < self.track_at then
+      if final_size == self.track_at then
+        self._tracked_node = self.tail
+      elseif final_size > self.track_at then
+        self._tracked_node = self._tracked_node.prev
+      else
+          return
+      end
+    end
+
+    self.tracked = self._tracked_node.item
+  end
+end
+
+
+-- Do you even do this in linked lists...?
+-- function LinkedList:remove(item)
+-- end
+
+function LinkedList:iter()
+  local current_node = self.head
+
+  return function()
+    local node = current_node
+    if not node then
+      return nil
+    end
+
+    current_node = current_node.next
+    return node.item
+  end
+end
+
+function LinkedList:ipairs()
+  local index = 0
+  local current_node = self.head
+
+  return function()
+    local node = current_node
+    if not node then
+      return nil
+    end
+
+    current_node = current_node.next
+    index = index + 1
+    return index, node.item, node
+  end
+end
+
+return LinkedList