Reconcile Neovim setup packages

lua/setup/init.lua

@@ -1,4 +1,5 @@
 local lock_path = vim.fs.joinpath(vim.fn.stdpath('config'), 'paq-lock.json')
+local paq_removed_status = 3
 
 local function clone_paq()
   local path = vim.fn.stdpath('data') .. '/site/pack/paqs/opt/paq-nvim'
@@ -19,32 +20,102 @@ local function load_paq()
   return paq
 end
 
-local function install_packages()
-  clone_paq()
-
+local function run_paq(event, operation)
   local done = false
   vim.api.nvim_create_autocmd('User', {
-    pattern = 'PaqDoneInstall',
+    pattern = event,
     once = true,
     callback = function()
       done = true
     end,
   })
 
-  local paq = load_paq()
-  paq.install()
+  operation()
 
   vim.wait(60000, function()
     return done
   end, 200)
 
-  if not done then
+  return done
+end
+
+local function install_packages()
+  clone_paq()
+
+  local paq = load_paq()
+  if not run_paq('PaqDoneInstall', paq.install) then
     print('Paq installation timeout or failed')
   else
     print('Paq installation completed')
   end
 end
 
+local function assert_no_unlisted_package_dirs(paq)
+  local expected_dirs = {}
+  for _, filter in ipairs({ 'installed', 'to_install' }) do
+    for _, pkg in ipairs(paq.query(filter)) do
+      expected_dirs[pkg.dir] = true
+    end
+  end
+
+  local stale_dirs = {}
+  local paq_path = vim.fs.joinpath(vim.fn.stdpath('data'), 'site', 'pack', 'paqs')
+  for _, packdir in ipairs({ 'start', 'opt' }) do
+    local path = vim.fs.joinpath(paq_path, packdir)
+    if vim.uv.fs_stat(path) then
+      for name, type in vim.fs.dir(path) do
+        local dir = vim.fs.joinpath(path, name)
+        if type == 'directory' and not expected_dirs[dir] then
+          table.insert(stale_dirs, dir)
+        end
+      end
+    end
+  end
+
+  if #stale_dirs > 0 then
+    error('Paq cleanup left unlisted package directories:\n' .. table.concat(stale_dirs, '\n'))
+  end
+end
+
+local function prune_removed_lock_entries()
+  if vim.fn.filereadable(lock_path) == 0 then
+    return
+  end
+
+  local raw = table.concat(vim.fn.readfile(lock_path), '\n')
+  local lock = vim.json.decode(raw)
+  local changed = false
+
+  for name, pkg in pairs(lock) do
+    if pkg.status == paq_removed_status then
+      lock[name] = nil
+      changed = true
+    end
+  end
+
+  if changed then
+    vim.fn.writefile({ vim.json.encode(lock) }, lock_path)
+  end
+end
+
+local function reconcile_packages()
+  clone_paq()
+
+  local paq = load_paq()
+  if not run_paq('PaqDoneRemove', paq.clean) then
+    print('Paq cleanup timeout or failed')
+    return
+  end
+  assert_no_unlisted_package_dirs(paq)
+  prune_removed_lock_entries()
+
+  if not run_paq('PaqDoneInstall', paq.install) then
+    print('Paq installation timeout or failed')
+  else
+    print('Paq packages reconciled')
+  end
+end
+
 local function install_languages()
   vim.cmd.packadd('mason.nvim')
   require('mason').setup()
@@ -58,7 +129,13 @@ end
 local function sync_packages()
   clone_paq()
   local paq = load_paq()
-  paq:sync()
+  if not run_paq('PaqDoneSync', function()
+    paq:sync()
+  end) then
+    print('Paq sync timeout or failed')
+  else
+    print('Paq sync completed')
+  end
 end
 
 local function fetch_lsp_configs()
@@ -94,8 +171,8 @@ local function create_command(name, callback, desc)
 end
 
 create_command('Setup', function()
-  print('> Installing packages...')
-  install_packages()
+  print('> Reconciling packages...')
+  reconcile_packages()
   print('\n> Installing languages: treesitter parsers, language servers, linters, formatters...')
   install_languages()
   print('\n=== Setup Finished ===\n')