1 files changed, 360 insertions, 0 deletions
diff --git a/lua/lvim/impatient.lua b/lua/lvim/impatient.lua
new file mode 100644
index 00000000..4fdc0026
--- /dev/null
+++ b/lua/lvim/impatient.lua
@@ -0,0 +1,360 @@
+-- modified version from https://github.com/lewis6991/impatient.nvim
+
+local vim = vim
+local uv = vim.loop
+local impatient_load_start = uv.hrtime()
+local api = vim.api
+local ffi = require "ffi"
+
+local get_option, set_option = api.nvim_get_option, api.nvim_set_option
+local get_runtime_file = api.nvim_get_runtime_file
+
+local impatient_dur
+
+local M = {
+  cache = {},
+  profile = nil,
+  dirty = false,
+  path = nil,
+  log = {},
+}
+
+_G.__luacache = M
+
+--{{{
+local cachepack = {}
+
+-- using double for packing/unpacking numbers has no conversion overhead
+-- 32-bit ARM causes a bus error when casting to double, so use int there
+local number_t = jit.arch ~= "arm" and "double" or "int"
+ffi.cdef("typedef " .. number_t .. " number_t;")
+
+local c_number_t = ffi.typeof "number_t[1]"
+local c_sizeof_number_t = ffi.sizeof "number_t"
+
+local out_buf = {}
+
+function out_buf.write_number(buf, num)
+  buf[#buf + 1] = ffi.string(c_number_t(num), c_sizeof_number_t)
+end
+
+function out_buf.write_string(buf, str)
+  out_buf.write_number(buf, #str)
+  buf[#buf + 1] = str
+end
+
+function out_buf.to_string(buf)
+  return table.concat(buf)
+end
+
+local in_buf = {}
+
+function in_buf.read_number(buf)
+  if buf.size < buf.pos then
+    error "buffer access violation"
+  end
+  local res = ffi.cast("number_t*", buf.ptr + buf.pos)[0]
+  buf.pos = buf.pos + c_sizeof_number_t
+  return res
+end
+
+function in_buf.read_string(buf)
+  local len = in_buf.read_number(buf)
+  local res = ffi.string(buf.ptr + buf.pos, len)
+  buf.pos = buf.pos + len
+
+  return res
+end
+
+function cachepack.pack(cache)
+  local total_keys = vim.tbl_count(cache)
+  local buf = {}
+
+  out_buf.write_number(buf, total_keys)
+  for k, v in pairs(cache) do
+    out_buf.write_string(buf, k)
+    out_buf.write_string(buf, v[1] or "")
+    out_buf.write_number(buf, v[2] or 0)
+    out_buf.write_string(buf, v[3] or "")
+  end
+
+  return out_buf.to_string(buf)
+end
+
+function cachepack.unpack(str, raw_buf_size)
+  if raw_buf_size == 0 or str == nil or (raw_buf_size == nil and #str == 0) then
+    return {}
+  end
+
+  local buf = {
+    ptr = raw_buf_size and str or ffi.new("const char[?]", #str, str),
+    pos = 0,
+    size = raw_buf_size or #str,
+  }
+  local cache = {}
+
+  local total_keys = in_buf.read_number(buf)
+  for _ = 1, total_keys do
+    local k = in_buf.read_string(buf)
+    local v = {
+      in_buf.read_string(buf),
+      in_buf.read_number(buf),
+      in_buf.read_string(buf),
+    }
+    cache[k] = v
+  end
+
+  return cache
+end
+--}}}
+
+local function log(...)
+  M.log[#M.log + 1] = table.concat({ string.format(...) }, " ")
+end
+
+function M.print_log()
+  for _, l in ipairs(M.log) do
+    print(l)
+  end
+end
+
+function M.enable_profile()
+  M.profile = {}
+  M.print_profile = function()
+    M.profile["lvim.impatient"] = {
+      resolve = 0,
+      load = impatient_dur,
+      loader = "standard",
+    }
+    require("lvim.impatient.profile").print_profile(M.profile)
+  end
+  vim.cmd [[command! LuaCacheProfile lua _G.__luacache.print_profile()]]
+end
+
+local function is_cacheable(path)
+  -- Don't cache files in /tmp since they are not likely to persist.
+  -- Note: Appimage versions of Neovim mount $VIMRUNTIME in /tmp in a unique
+  -- directory on each launch.
+  return not vim.startswith(path, "/tmp/")
+end
+
+local function hash(modpath)
+  local stat = uv.fs_stat(modpath)
+  if stat then
+    return stat.mtime.sec
+  end
+end
+
+local function hrtime()
+  if M.profile then
+    return uv.hrtime()
+  end
+end
+
+local function load_package_with_cache(name, loader)
+  local resolve_start = hrtime()
+
+  local basename = name:gsub("%.", "/")
+  local paths = { "lua/" .. basename .. ".lua", "lua/" .. basename .. "/init.lua" }
+
+  for _, path in ipairs(paths) do
+    local modpath = get_runtime_file(path, false)[1]
+    if modpath then
+      local load_start = hrtime()
+      local chunk, err = loadfile(modpath)
+
+      if M.profile then
+        M.profile[name] = {
+          resolve = load_start - resolve_start,
+          load = hrtime() - load_start,
+          loader = loader or "standard",
+        }
+      end
+
+      if chunk == nil then
+        return err
+      end
+
+      if is_cacheable(modpath) then
+        log("Creating cache for module %s", name)
+        M.cache[name] = { modpath, hash(modpath), string.dump(chunk) }
+        M.dirty = true
+      else
+        log("Unable to cache module %s", name)
+      end
+
+      return chunk
+    end
+  end
+  return nil
+end
+
+local reduced_rtp
+
+-- Speed up non-cached loads by reducing the rtp path during requires
+function M.update_reduced_rtp()
+  local luadirs = get_runtime_file("lua/", true)
+
+  for i = 1, #luadirs do
+    luadirs[i] = luadirs[i]:sub(1, -6)
+  end
+
+  reduced_rtp = table.concat(luadirs, ",")
+end
+
+local function load_package_with_cache_reduced_rtp(name)
+  local orig_rtp = get_option "runtimepath"
+  local orig_ei = get_option "eventignore"
+
+  if not reduced_rtp then
+    M.update_reduced_rtp()
+  end
+
+  set_option("eventignore", "all")
+  set_option("rtp", reduced_rtp)
+
+  local found = load_package_with_cache(name, "reduced")
+
+  set_option("rtp", orig_rtp)
+  set_option("eventignore", orig_ei)
+
+  return found
+end
+
+local function load_from_cache(name)
+  local resolve_start = hrtime()
+  if M.cache[name] == nil then
+    log("No cache for module %s", name)
+    return "No cache entry"
+  end
+
+  local modpath, mhash, codes = unpack(M.cache[name])
+
+  if mhash ~= hash(modpath) then
+    log("Stale cache for module %s", name)
+    M.cache[name] = nil
+    M.dirty = true
+    return "Stale cache"
+  end
+
+  local load_start = hrtime()
+  local chunk = loadstring(codes)
+
+  if M.profile then
+    M.profile[name] = {
+      resolve = load_start - resolve_start,
+      load = hrtime() - load_start,
+      loader = "cache",
+    }
+  end
+
+  if not chunk then
+    M.cache[name] = nil
+    M.dirty = true
+    log("Error loading cache for module. Invalidating", name)
+    return "Cache error"
+  end
+
+  return chunk
+end
+
+function M.save_cache()
+  if M.dirty then
+    log("Updating cache file: %s", M.path)
+    local f = io.open(M.path, "w+b")
+    f:write(cachepack.pack(M.cache))
+    f:flush()
+    M.dirty = false
+  end
+end
+
+function M.clear_cache()
+  M.cache = {}
+  os.remove(M.path)
+end
+
+impatient_dur = uv.hrtime() - impatient_load_start
+
+function M.setup(opts)
+  opts = opts or {}
+  M.path = opts.path or vim.fn.stdpath "cache" .. "/lvim_cache"
+
+  if opts.enable_profiling then
+    M.enable_profile()
+  end
+
+  local impatient_setup_start = uv.hrtime()
+  local stat = uv.fs_stat(M.path)
+  if stat then
+    log("Loading cache file %s", M.path)
+    local ok
+    -- Linux/macOS lets us easily mmap the cache file for faster reads without passing to Lua
+    if jit.os == "Linux" or jit.os == "OSX" then
+      local size = stat.size
+
+      local C = ffi.C
+      local O_RDONLY = 0x00
+      local PROT_READ = 0x01
+      local MAP_PRIVATE = 0x02
+
+      ffi.cdef [[
+      int open(const char *pathname, int flags);
+      int close(int fd);
+      void *mmap(void *addr, size_t length, int prot, int flags, int fd, long int offset);
+      int munmap(void *addr, size_t length);
+      ]]
+      local f = C.open(M.path, O_RDONLY)
+
+      local addr = C.mmap(nil, size, PROT_READ, MAP_PRIVATE, f, 0)
+      ok = ffi.cast("intptr_t", addr) ~= -1
+
+      if ok then
+        M.cache = cachepack.unpack(ffi.cast("char *", addr), size)
+        C.munmap(addr, size)
+      end
+
+      C.close(f)
+    else
+      local f = io.open(M.path, "rb")
+      ok, M.cache = pcall(function()
+        return cachepack.unpack(f:read "*a")
+      end)
+    end
+
+    if not ok then
+      log("Corrupted cache file, %s. Invalidating...", M.path)
+      os.remove(M.path)
+      M.cache = {}
+    end
+    M.dirty = not ok
+  end
+
+  local insert = table.insert
+  local package = package
+
+  -- Fix the position of the preloader. This also makes loading modules like 'ffi'
+  -- and 'bit' quicker
+  if package.loaders[1] == vim._load_package then
+    -- Move vim._load_package to the second position
+    local vim_load = table.remove(package.loaders, 1)
+    insert(package.loaders, 2, vim_load)
+  end
+
+  insert(package.loaders, 2, load_from_cache)
+  insert(package.loaders, 3, load_package_with_cache_reduced_rtp)
+  insert(package.loaders, 4, load_package_with_cache)
+
+  vim.cmd [[
+    augroup impatient
+      autocmd VimEnter,VimLeave * lua _G.__luacache.save_cache()
+      autocmd OptionSet runtimepath lua _G.__luacache.update_reduced_rtp(true)
+    augroup END
+
+    command! LuaCacheClear lua _G.__luacache.clear_cache()
+    command! LuaCacheLog   lua _G.__luacache.print_log()
+  ]]
+
+  impatient_dur = impatient_dur + (uv.hrtime() - impatient_setup_start)
+end
+
+return M