unique.lua

local task_list = require("overseer.task_list")
local util = require("overseer.util")
---@type overseer.ComponentFileDefinition
return {
  desc = "Ensure that this task does not have any duplicates",
  -- Doesn't make sense for user to add this using a form.
  editable = false,
  params = {
    replace = {
      desc = "If a prior task exists, replace it. When false, will restart the existing task and dispose the current task",
      long_desc = "Note that when this is false a new task that is created will restart the existing one and _dispose itself_. This can lead to unexpected behavior if you are creating a task and then trying to use that reference (to run actions on it, use it as a dependency, etc)",
      type = "boolean",
      default = true,
    },
    restart_interrupts = {
      desc = "When replace = false, should restarting the existing task interrupt it",
      type = "boolean",
      default = true,
    },
    soft = {
      desc = "Only dispose duplicate tasks if they are completed. Implies replace = true.",
      type = "boolean",
      default = false,
    },
    compare = {
      desc = "Comparison function that returns true when a task is equal",
      type = "opaque",
      optional = true,
    },
  },
  constructor = function(params)
    local compare = params.compare or function(a, b)
      return a.name == b.name
    end
    return {
      on_pre_start = function(_, task)
        local tasks = task_list.list_tasks()
        for _, t in ipairs(tasks) do
          if t ~= task and compare(t, task) then
            if params.replace then
              if t:is_complete() or not params.soft then
                task:subscribe("on_start", function()
                  util.replace_buffer_in_wins(t:get_bufnr(), task:get_bufnr())
                  return false
                end)
                t:dispose(true)
              end
            else
              task:dispose(true)
              t:restart(params.restart_interrupts)
              return false
            end
          end
        end
      end,
    }
  end,
}