refactor(util): unify debounce helpers into Debouncer class

lua/linter.lua

@@ -425,11 +425,12 @@ function Linter.add(bufnr, config)
         return
     end
 
+    local debouncer = util.debounce(function()
+        linter:run()
+    end, config.debounce)
     vim.api.nvim_create_autocmd(config.events, {
         buffer = linter.bufnr,
-        callback = util.debounce(function()
-            linter:run()
-        end, config.debounce),
+        callback = function() debouncer:call() end,
         group = linter.augroup,
     })
 

lua/pack.lua

@@ -1,4 +1,5 @@
 local log = require("log")
+local util = require("util")
 
 local config_dir = vim.fn.stdpath("config")
 
@@ -82,10 +83,9 @@ local function run_build(plugin)
         plugin.build(plugin)
         return
     elseif type(plugin.build) == "table" then
-        local ret = vim.system(
-            plugin.build --[[@as table]],
-            { cwd = plugin.path }
-        ):wait()
+        local ret =
+            vim.system(plugin.build --[[@as table]], { cwd = plugin.path })
+                :wait()
         if ret.code ~= 0 then
             log.error("Build failed for %s: %s", plugin.name, ret.stderr or "")
         end
@@ -120,7 +120,8 @@ local function process_events(plugin, events)
     end
 
     for _, ev in ipairs(events) do
-        if ev.data.spec.name == plugin.name
+        if
+            ev.data.spec.name == plugin.name
             and ev.event == "PackChanged"
             and (ev.data.kind == "install" or ev.data.kind == "update")
         then
@@ -136,8 +137,8 @@ end
 ---@type uv.uv_fs_event_t?
 local watcher = nil
 
----@type table<string, uv.uv_timer_t>
-local timers = {}
+---@type ow.Util.Debouncer?
+local reload = nil
 
 ---@class ow.Pack
 ---@field plugins ow.Pack.Plugin[]
@@ -147,12 +148,16 @@ local M = {
 
 ---@return string[]
 function M.get_names()
-    return vim.tbl_map(function(p) return p.name end, M.plugins)
+    return vim.tbl_map(function(p)
+        return p.name
+    end, M.plugins)
 end
 
 ---@return string[]
 function M.get_paths()
-    return vim.tbl_map(function(p) return p.path end, M.plugins)
+    return vim.tbl_map(function(p)
+        return p.path
+    end, M.plugins)
 end
 
 ---@param name string
@@ -196,61 +201,29 @@ function M.watch()
         return
     end
 
-    watcher:start(
-        plugins_dir,
-        {},
-        vim.schedule_wrap(function(err, filename)
-            if err then
-                log.error("Watch error: %s", err)
-                return
-            end
-
-            if not filename or not filename:match("%.lua$") then
-                return
-            end
-
-            ---@type uv.uv_timer_t?
-            local timer = timers[filename]
-            if not timer then
-                timer, err_msg, err_name = vim.uv.new_timer()
-                if not timer then
-                    log.error(
-                        "Failed to create new timer: %s (%s)", err_msg, err_name
-                    )
-                    return
-                end
-                timers[filename] = timer
-            else
-                timer:stop()
-            end
-
-            timer:start(
-                100,
-                0,
-                vim.schedule_wrap(function()
-                    timer:stop()
-                    timer:close()
-                    timers[filename] = nil
-
-                    local path = plugins_dir .. "/" .. filename
+    reload = util.debounce(function(filename)
+        local path = vim.fs.joinpath(plugins_dir, filename)
         if not vim.uv.fs_stat(path) then
             return
         end
-
         local ok, load_err = exec(path)
         if ok then
             log.info("Reloaded %s", filename)
         else
-                        log.error(
-                            "Failed to reload %s: %s",
-                            filename,
-                            load_err
-                        )
+            log.error("Failed to reload %s: %s", filename, load_err)
         end
+    end, 100)
+
+    watcher:start(plugins_dir, {}, function(err, filename)
+        if err then
+            log.error("Watch error: %s", err)
+            return
+        end
+        if not filename or not filename:match("%.lua$") then
+            return
+        end
+        reload:call(filename)
     end)
-            )
-        end)
-    )
 end
 
 function M.unwatch()
@@ -258,10 +231,9 @@ function M.unwatch()
         return
     end
 
-    for key, timer in pairs(timers) do
-        timer:stop()
-        timer:close()
-        timers[key] = nil
+    if reload then
+        reload:cancel()
+        reload = nil
     end
 
     watcher:stop()
@@ -281,12 +253,14 @@ function M.setup(specs)
             ---@param ev ow.Pack.Event
             callback = function(ev)
                 local name = ev.data.spec.name
-                if not name then return end
+                if not name then
+                    return
+                end
                 if not events[name] then
                     events[name] = {}
                 end
                 table.insert(events[name], ev)
-            end
+            end,
         }
     )
     vim.pack.add(vim.tbl_map(to_pack_spec, specs), {
@@ -309,7 +283,7 @@ function M.setup(specs)
             if not d.ts_parser then
                 vim.cmd.packadd(plugin.name)
             end
-        end
+        end,
     })
     vim.api.nvim_del_autocmd(id)
 

lua/util.lua

@@ -295,49 +295,67 @@ function Util.is_list_or_nil(val, t)
     end
 end
 
---- Creates a debounced function that delays execution of `fn` until after `delay` milliseconds have
---- elapsed since the last time it was invoked.
----@param fn fun(...) Function to be debounced
----@param delay integer Debounce delay in milliseconds
----@return fun(...) function Debounced function
-function Util.debounce(fn, delay)
-    ---@type uv.uv_timer_t?
-    local timer = nil
+local NIL_KEY = {}
 
-    return function(...)
+---@class ow.Util.Debouncer
+---@field private _fn fun(id: any, ...)
+---@field private _delay integer
+---@field private _timers table<any, uv.uv_timer_t>
+local Debouncer = {}
+Debouncer.__index = Debouncer
+
+---@param fn fun(id: any, ...)
+---@param delay integer
+---@return ow.Util.Debouncer
+function Debouncer.new(fn, delay)
+    return setmetatable({ _fn = fn, _delay = delay, _timers = {} }, Debouncer)
+end
+
+---@param id? any
+---@param ... any
+function Debouncer:call(id, ...)
+    local key = id == nil and NIL_KEY or id
     local args = vim.F.pack_len(...)
-        if timer then
-            timer:stop()
-            timer = nil
-        end
+    self:cancel(id)
+    self._timers[key] = vim.defer_fn(function()
+        self._timers[key] = nil
+        self._fn(id, vim.F.unpack_len(args))
+    end, self._delay)
+end
 
-        timer = vim.defer_fn(function()
-            timer = nil
-            fn(vim.F.unpack_len(args))
-        end, delay)
+---@param timer uv.uv_timer_t
+local function dispose(timer)
+    timer:stop()
+    timer:close()
+end
+
+---@param id? any
+function Debouncer:cancel(id)
+    local key = id == nil and NIL_KEY or id
+    local timer = self._timers[key]
+    if timer then
+        dispose(timer)
+        self._timers[key] = nil
     end
 end
 
+function Debouncer:cancel_all()
+    for _, t in pairs(self._timers) do
+        dispose(t)
+    end
+    self._timers = {}
+end
+
+Util.Debouncer = Debouncer
+
 --- Creates a debounced function that delays execution of `fn` until after `delay` milliseconds have
---- elapsed since the last time it was invoked with the same unique identifier.
----@param fn fun(...) Function to be debounced
+--- elapsed since the last time it was invoked. Use `d:call(id, ...)` to debounce per-id, or
+--- `d:call(...)` for a single shared slot.
+---@param fn fun(id: any, ...) Function to be debounced
 ---@param delay integer Debounce delay in milliseconds
----@return fun(id: any, ...) function Debounced function, where `id` is a unique identifier
-function Util.debounce_with_id(fn, delay)
-    local map = {}
-
-    return function(id, ...)
-        local args = vim.F.pack_len(...)
-        if map[id] then
-            map[id]:stop()
-            map[id] = nil
-        end
-
-        map[id] = vim.defer_fn(function()
-            map[id] = nil
-            fn(vim.F.unpack_len(args))
-        end, delay)
-    end
+---@return ow.Util.Debouncer
+function Util.debounce(fn, delay)
+    return Debouncer.new(fn, delay)
 end
 
 function Util.get_hl_source(name)