fix: Clear virtual text immediately on cursor move

lua/gitblame/init.lua

@@ -58,6 +58,29 @@ local function clear_virtual_text()
  vim.api.nvim_buf_del_extmark(0, NAMESPACE_ID, 1)
 end
 
+-- A luv timer object. Used exclusively for debouncing in `debounce`.
+local debounce_timer = nil
+
+-- Debounces `func` by `delay` milliseconds.
+-- **IMPORTANT:** This refers to a single timer object (`debounce_timer`) for the debounce; beware!
+---@param func function the function which will be wrapped
+---@param delay integer time in milliseconds
+---@return function debounced_func the debounced function which you can execute
+local function debounce(func, delay)
+ return function(...)
+ local args = { ... }
+ if debounce_timer then
+ debounce_timer:stop()
+ debounce_timer = nil
+ end
+
+ debounce_timer = vim.defer_fn(function()
+ func(unpack(args))
+ debounce_timer = nil
+ end, delay)
+ end
+end
+
 ---@param blames table[]
 ---@param filepath string
 ---@param lines string[]
@@ -283,8 +306,9 @@ end
 ---@field startline number
 ---@field endline number
 
+---@param filepath string
 ---@param info BlameInfo?
----@param callback fun(blame_text: string?)
+---@param callback fun(blame_text: string|nil)
 local function get_blame_text(filepath, info, callback)
  local is_info_commit = info
  and info.author
@@ -621,61 +645,79 @@ local function clear_all_extmarks()
  end
 end
 
--- this function is uesed to verify the config info for debounce
---- @return boolean
-local verify_debounce_info = function()
- if vim.g.gitblame_schedule_event ~= "CursorMoved" and vim.g.gitblame_schedule_event ~= "CursorHold" then
- vim.notify(
- string.format("event is error: %s, it just can be CursorMoved or CursorHold", vim.g.gitblame_schedule_event),
- vim.log.levels.ERROR,
- {}
- )
- return false
- end
- if vim.g.gitblame_clear_event ~= "CursorMovedI" and vim.g.gitblame_clear_event ~= "CursorHoldI" then
- vim.notify(
- string.format("event is error: %s, it just can be CursorMoved or CursorHold", vim.g.gitblame_clear_event),
- vim.log.levels.ERROR,
- {}
+-- Validates the `parameter_name` against `available_values`. Returns an error message
+-- if `parameter_name` doesn't match `available_values`.
+--
+---@param parameter_name string
+---@param available_values object[]
+---@return string|nil
+local function validate_enum_parameter(parameter_name, available_values)
+ local current_value = vim.g[parameter_name]
+
+ if not vim.tbl_contains(available_values, current_value) then
+ return string.format(
+ "Invalid value for `%s`: %s. Available values are %s",
+ parameter_name,
+ current_value,
+ vim.inspect(available_values)
  )
- return false
  end
+end
+
+-- Verifies the debounce configuration and displays an error message if it is invalid.
+-- Returns `true` if the configuration is valid, `false` otherwise.
+--
+---@return boolean
+local function verify_debounce_configuration()
+ local error_message = validate_enum_parameter("gitblame_schedule_event", { "CursorMoved", "CursorHold" })
+ or validate_enum_parameter("gitblame_clear_event", { "CursorMovedI", "CursorHoldI" })
 
  if type(vim.g.gitblame_delay) ~= "number" or vim.g.gitblame_delay < 0 then
- vim.notify(
- string.format("delay is error: %s, it just can be number", vim.g.gitblame_delay),
- vim.log.levels.ERROR,
- {}
- )
- return false
+ error_message =
+ string.format("Invald value for `gitblame_delay`: %s. It should be a positive number", vim.g.gitblame_delay)
+ end
+
+ if error_message ~= nil then
+ vim.notify(error_message, vim.log.levels.ERROR, {})
+ end
+
+ return error_message == nil
+end
+
+---@type function
+local function maybe_clear_virtual_text_and_schedule_info_display()
+ local position_info = get_position_info()
+
+ if not position_info.is_on_same_line and not need_update_after_horizontal_move then
+ clear_virtual_text()
  end
 
- return true
+ debounce(schedule_show_info_display, math.floor(vim.g.gitblame_delay))()
 end
 
 local function set_autocmds()
  local autocmd = vim.api.nvim_create_autocmd
  local group = vim.api.nvim_create_augroup("gitblame", { clear = true })
 
- if not verify_debounce_info() then
+ if not verify_debounce_configuration() then
  return
  end
 
- --- @type "CursorMoved" | "CursorHold"
+ ---@type "CursorMoved" | "CursorHold"
  local event_schedule = vim.g.gitblame_schedule_event
- --- @type "CursorMovedI" | "CursorHoldI"
+ ---@type "CursorMovedI" | "CursorHoldI"
  local event_clear = vim.g.gitblame_clear_event
 
- --- @type function
+ ---@type function
  local func_schedule = schedule_show_info_display
  if event_schedule == "CursorMoved" then
- func_schedule = utils.debounce(schedule_show_info_display, math.floor(vim.g.gitblame_delay))
+ func_schedule = maybe_clear_virtual_text_and_schedule_info_display
  end
 
- --- @type function
+ ---@type function
  local func_clear = clear_virtual_text
  if event_clear == "CursorMovedI" then
- func_clear = utils.debounce(clear_virtual_text, math.floor(vim.g.gitblame_delay))
+ func_clear = debounce(clear_virtual_text, math.floor(vim.g.gitblame_delay))
  end
 
  autocmd(event_schedule, { callback = func_schedule, group = group })

lua/gitblame/utils.lua

@@ -159,23 +159,4 @@ function M.shallowcopy(orig)
  return copy
 end
 
--- debounce function
----@param func function the function which will be wrapped
----@param delay integer time, millisecond
-function M.debounce(func, delay)
- local timer = nil
- return function(...)
- local args = { ... }
- if timer then
- timer:stop()
- timer = nil
- end
-
- timer = vim.defer_fn(function()
- func(unpack(args))
- timer = nil
- end, delay)
- end
-end
-
 return M