feat: move watchers to repo objects

lua/gitsigns/async.lua

@@ -99,7 +99,8 @@ local function run(func, callback, ...)
 
  assert(type(fn) == 'function', 'type error :: expected func')
 
- local args = { select(4, unpack(ret)) }
+ --- @type any[]
+ local args = { unpack(ret, 4, table.maxn(ret)) }
  args[nargs] = step
 
  local r = fn(unpack(args, 1, nargs))
@@ -144,7 +145,7 @@ function M.wait(argc, func, ...)
 end
 
 --- Creates an async function with a callback style function.
---- @param argc number The number of arguments of func. Must be included.
+--- @param argc integer The number of arguments of func. Must be included.
 --- @param func function A callback style function to be converted. The last argument must be the callback.
 --- @return function: Returns an async function
 function M.wrap(argc, func)

lua/gitsigns/attach.lua

@@ -11,6 +11,7 @@ local config = require('gitsigns.config').config
 local dprint = log.dprint
 local dprintf = log.dprintf
 local throttle_by_id = require('gitsigns.debounce').throttle_by_id
+local debounce_trailing = require('gitsigns.debounce').debounce_trailing
 
 local api = vim.api
 local uv = vim.loop
@@ -216,6 +217,105 @@ local function get_buf_context(bufnr)
  }
 end
 
+--- @param bufnr integer
+--- @param old_relpath string
+local function handle_moved(bufnr, old_relpath)
+ local bcache = assert(cache[bufnr])
+ local git_obj = bcache.git_obj
+
+ local new_name = git_obj:has_moved()
+ if new_name then
+ dprintf('File moved to %s', new_name)
+ git_obj.relpath = new_name
+ if not git_obj.orig_relpath then
+ git_obj.orig_relpath = old_relpath
+ end
+ elseif git_obj.orig_relpath then
+ local orig_file = git_obj.repo.toplevel .. util.path_sep .. git_obj.orig_relpath
+ if not git_obj:file_info(orig_file).relpath then
+ return
+ end
+ --- File was moved in the index, but then reset
+ dprintf('Moved file reset')
+ git_obj.relpath = git_obj.orig_relpath
+ git_obj.orig_relpath = nil
+ else
+ -- File removed from index, do nothing
+ return
+ end
+
+ git_obj.file = git_obj.repo.toplevel .. util.path_sep .. git_obj.relpath
+ bcache.file = git_obj.file
+ git_obj:update()
+ if not manager.schedule(bufnr) then
+ return
+ end
+
+ local bufexists = util.bufexists(bcache.file)
+ local old_name = api.nvim_buf_get_name(bufnr)
+
+ if not bufexists then
+ -- Do not trigger BufFilePre/Post
+ -- TODO(lewis6991): figure out how to avoid reattaching without
+ -- disabling all autocommands.
+ util.noautocmd({ 'BufFilePre', 'BufFilePost' }, function()
+ util.buf_rename(bufnr, bcache.file)
+ end)
+ end
+
+ local msg = bufexists and 'Cannot rename' or 'Renamed'
+ dprintf('%s buffer %d from %s to %s', msg, bufnr, old_name, bcache.file)
+end
+
+--- @async
+--- @param bufnr integer
+local function watcher_handler0(bufnr)
+ local __FUNC__ = 'watcher_handler'
+
+ -- Avoid cache hit for detached buffer
+ -- ref: https://github.com/lewis6991/gitsigns.nvim/issues/956
+ if not manager.schedule(bufnr) then
+ dprint('buffer invalid (1)')
+ return
+ end
+
+ local git_obj = cache[bufnr].git_obj
+
+ Status:update(bufnr, { head = git_obj.repo.abbrev_head })
+
+ local was_tracked = git_obj.object_name ~= nil
+ local old_relpath = git_obj.relpath
+
+ git_obj:update()
+ if not manager.schedule(bufnr) then
+ dprint('buffer invalid (3)')
+ return
+ end
+
+ if config.watch_gitdir.follow_files and was_tracked and not git_obj.object_name then
+ -- File was tracked but is no longer tracked. Must of been removed or
+ -- moved. Check if it was moved and switch to it.
+ handle_moved(bufnr, old_relpath)
+ if not manager.schedule(bufnr) then
+ dprint('buffer invalid (4)')
+ return
+ end
+ end
+
+ cache[bufnr]:invalidate(true)
+
+ require('gitsigns.manager').update(bufnr)
+end
+
+--- Debounce to:
+--- - wait for all changes to the gitdir to complete.
+--- Throttle to:
+--- - ensure handler is only triggered once per git operation.
+--- - prevent updates to the same buffer from interleaving as the handler is
+--- async.
+local watcher_handler =
+ debounce_trailing(200, async.create(1, throttle_by_id(watcher_handler0, true)), 1)
+
 --- Ensure attaches cannot be interleaved for the same buffer.
 --- Since attaches are asynchronous we need to make sure an attach isn't
 --- performed whilst another one is in progress.
@@ -325,8 +425,9 @@ local attach_throttled = throttle_by_id(function(cbuf, ctx, aucmd)
  })
 
  if config.watch_gitdir.enable then
- local watcher = require('gitsigns.watcher')
- cache[cbuf].gitdir_watcher = watcher.watch_gitdir(cbuf, git_obj.repo.gitdir)
+ cache[cbuf].deregister_watcher = git_obj.repo:register_callback(function()
+ watcher_handler(cbuf)
+ end)
  end
 
  if not api.nvim_buf_is_loaded(cbuf) then

lua/gitsigns/cache.lua

@@ -17,7 +17,7 @@ local M = {
 --- @field hunks_staged? Gitsigns.Hunk.Hunk[]
 ---
 --- @field staged_diffs? Gitsigns.Hunk.Hunk[]
---- @field gitdir_watcher? uv.uv_fs_event_t
+--- @field deregister_watcher? fun()
 --- @field git_obj Gitsigns.GitObj
 --- @field blame? table<integer,Gitsigns.BlameInfo?>
 local CacheEntry = M.CacheEntry
@@ -127,9 +127,8 @@ function CacheEntry:get_blame(lnum, opts)
 end
 
 function CacheEntry:destroy()
- local w = self.gitdir_watcher
- if w and not w:is_closing() then
- w:close()
+ if self.deregister_watcher then
+ self.deregister_watcher()
  end
  self.git_obj.repo:unref()
 end

lua/gitsigns/git/repo.lua

@@ -22,6 +22,7 @@ local uv = vim.uv or vim.loop
 --- Username configured for the repo.
 --- Needed for to determine "You" in current line blame.
 --- @field username string
+--- @field watcher_callbacks table<fun(), true>
 local M = {}
 
 --- Run git command the with the objects gitdir and toplevel
@@ -96,6 +97,48 @@ function M:update_abbrev_head()
  self.abbrev_head = info.abbrev_head
 end
 
+--- vim.inspect but on one line
+--- @param x any
+--- @return string
+local function inspect(x)
+ return vim.inspect(x, { indent = '', newline = ' ' })
+end
+
+function M:_watcher_cb(err, filename, events)
+ if err then
+ log.dprintf('Git dir update error: %s', err)
+ return
+ end
+
+ -- The luv docs say filename is passed as a string but it has been observed
+ -- to sometimes be nil.
+ -- https://github.com/lewis6991/gitsigns.nvim/issues/848
+ if not filename then
+ log.eprint('No filename')
+ return
+ end
+
+ log.dprintf("Git dir update: '%s' %s", filename, inspect(events))
+
+ async.run(function()
+ self:update_abbrev_head()
+
+ for cb in pairs(self.watcher_callbacks) do
+ cb()
+ end
+ end)
+end
+
+--- @param cb fun()
+--- @return fun() deregister
+function M:register_callback(cb)
+ self.watcher_callbacks[cb] = true
+
+ return function()
+ self.watcher_callbacks[cb] = nil
+ end
+end
+
 --- @async
 --- @private
 --- @param info Gitsigns.RepoInfo
@@ -110,6 +153,12 @@ local function new(info)
  end
 
  self.username = self:command({ 'config', 'user.name' }, { ignore_error = true })[1]
+ self.watcher_callbacks = {}
+
+ local w = assert(uv.new_fs_event())
+ w:start(self.gitdir, {}, function(err, filename, events)
+ self:_watcher_cb(err, filename, events)
+ end)
 
  return self
 end