feat(profile): added accurate startuptime to ui/stats/docs

lua/lazy/stats.lua

@@ -0,0 +1,56 @@
+local M = {}
+
+---@class LazyStats
+M._stats = {
+  -- startuptime in milliseconds till UIEnter
+  startuptime = 0,
+  -- when true, startuptime is the accurate cputime for the Neovim process. (Linux & Macos)
+  -- this is more accurate than `nvim --startuptime`, and as such will be slightly higher
+  -- when false, startuptime is calculated based on a delta with a timestamp when lazy started.
+  startuptime_cputime = false,
+  count = 0, -- total number of plugins
+  loaded = 0, -- number of loaded plugins
+}
+
+function M.on_ui_enter()
+  if not M.C then
+    pcall(function() end)
+  end
+
+  local ok = pcall(function()
+    local ffi = require("ffi")
+    ffi.cdef([[
+        typedef long time_t;
+        typedef int clockid_t;
+
+        typedef struct timespec {
+          time_t   tv_sec;        /* seconds */
+          long     tv_nsec;       /* nanoseconds */
+        } nanotime;
+        int clock_gettime(clockid_t clk_id, struct timespec *tp);
+      ]])
+    local pnano = assert(ffi.new("nanotime[?]", 1))
+    local CLOCK_PROCESS_CPUTIME_ID = jit.os == "OSX" and 12 or 2
+    ffi.C.clock_gettime(CLOCK_PROCESS_CPUTIME_ID, pnano)
+    M._stats.startuptime = tonumber(pnano[0].tv_sec) / 1e6 + tonumber(pnano[0].tv_nsec) / 1e6
+    M._stats.startuptime_cputime = true
+  end)
+  if not ok then
+    M._stats.startuptime = (vim.loop.hrtime() - require("lazy")._start) / 1e6
+  end
+  vim.cmd([[do User LazyVimStarted]])
+end
+
+function M.stats()
+  M._stats.count = 0
+  M._stats.loaded = 0
+  for _, plugin in pairs(require("lazy.core.config").plugins) do
+    M._stats.count = M._stats.count + 1
+    if plugin._.loaded then
+      M._stats.loaded = M._stats.loaded + 1
+    end
+  end
+  return M._stats
+end
+
+return M