feat(defaults): session data in $XDG_STATE_HOME #15583

See: 4f2884e16d

- Move session persistent data to $XDG_STATE_HOME Change 'directory',
  'backupdir', 'undodir', 'viewdir' and 'shadafile' default location to
  $XDG_STATE_HOME/nvim.
- Move logs to $XDG_STATE_HOME, too.
- Add stdpath('log') support.

Fixes: #14805

man/nvim.1

@@ -188,7 +188,7 @@ loading plugins is also skipped.
 Use
 .Ar shada
 instead of the default
-.Pa ~/.local/share/nvim/shada/main.shada .
+.Pa ~/.local/state/nvim/shada/main.shada .
 If
 .Ar shada
 is
@@ -326,7 +326,7 @@ Print version information and exit.
 .Sh ENVIRONMENT
 .Bl -tag -width Fl
 .It Ev NVIM_LOG_FILE
-Low-level log file, usually found at ~/.cache/nvim/log.
+Low-level log file, usually found at ~/.local/state/nvim/log.
 :help $NVIM_LOG_FILE
 .It Ev VIM
 Used to locate user files, such as init.vim.
@@ -340,12 +340,20 @@ Path to the user-local configuration directory, see
 Defaults to
 .Pa ~/.config .
 :help xdg
-.It Ev XDG_DATA_HOME
+.It Ev XDG_STATE_HOME
 Like
 .Ev XDG_CONFIG_HOME ,
 but used to store data not generally edited by the user,
 namely swap, backup, and ShaDa files.
 Defaults to
+.Pa ~/.local/state .
+:help xdg
+.It Ev XDG_DATA_HOME
+Like
+.Ev XDG_CONFIG_HOME ,
+but used to store data not generally edited by the user,
+things like runtime files.
+Defaults to
 .Pa ~/.local/share .
 :help xdg
 .It Ev VIMINIT

runtime/doc/builtin.txt

@@ -7465,14 +7465,17 @@ stdpath({what})					*stdpath()* *E6100*
 		directories.
 
 		{what}       Type    Description ~
-		cache        String  Cache directory. Arbitrary temporary
+		cache        String  Cache directory: arbitrary temporary
 		                     storage for plugins, etc.
-		config       String  User configuration directory. The
+		config       String  User configuration directory. |init.vim|
-		                     |init.vim| is stored here.
+		                     is stored here.
-		config_dirs  List    Additional configuration directories.
+		config_dirs  List    Other configuration directories.
 		data         String  User data directory. The |shada-file|
 		                     is stored here.
-		data_dirs    List    Additional data directories.
+		data_dirs    List    Other data directories.
+		log          String  Logs directory (for use by plugins too).
+		state        String  Session state directory: storage for file
+				     drafts, undo history, shada, etc.
 
 		Example: >
 			:echo stdpath("config")

runtime/doc/options.txt

@@ -841,7 +841,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	again not rename the file.
 
 						*'backupdir'* *'bdir'*
-'backupdir' 'bdir'	string	(default ".,$XDG_DATA_HOME/nvim/backup//")
+'backupdir' 'bdir'	string	(default ".,$XDG_STATE_HOME/nvim/backup//")
 			global
 	List of directories for the backup file, separated with commas.
 	- The backup file will be created in the first directory in the list
@@ -2063,7 +2063,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	{char2}.  See |digraphs|.
 
 						*'directory'* *'dir'*
-'directory' 'dir'	string	(default "$XDG_DATA_HOME/nvim/swap//")
+'directory' 'dir'	string	(default "$XDG_STATE_HOME/nvim/swap//")
 			global
 	List of directory names for the swap file, separated with commas.
 
@@ -3502,7 +3502,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	option.  For '@' only characters up to 255 are used.
 	Careful: If you change this option, it might break expanding
 	environment variables.  E.g., when '/' is included and Vim tries to
-	expand "$HOME/.local/share/nvim/shada/main.shada".  Maybe you should 
+	expand "$HOME/.local/state/nvim/shada/main.shada".  Maybe you should
 	change 'iskeyword' instead.
 
 						*'iskeyword'* *'isk'*
@@ -4942,9 +4942,12 @@ A jump table for the options with a short description can be found at |Q_op|.
 	   but are not part of the Nvim distribution. XDG_DATA_DIRS defaults
 	   to /usr/local/share/:/usr/share/, so system administrators are
 	   expected to install site plugins to /usr/share/nvim/site.
-	5. $VIMRUNTIME, for files distributed with Neovim.
+	5. Applications state home directory, for files that contain your
+	   session state (eg. backupdir, viewdir, undodir, etc).
+	   Given by `stdpath("state")`.  |$XDG_STATE_HOME|
+	6. $VIMRUNTIME, for files distributed with Neovim.
 							*after-directory*
-	6, 7, 8, 9. In after/ subdirectories of 1, 2, 3 and 4, with reverse 
+	7, 8, 9, 10. In after/ subdirectories of 1, 2, 3 and 4, with reverse
 	   ordering.  This is for preferences to overrule or add to the 
 	   distributed defaults or system-wide settings (rarely needed).
 
@@ -6623,7 +6626,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 'ttyfast' 'tf'		Removed. |vim-differences|
 
 						*'undodir'* *'udir'* *E5003*
-'undodir' 'udir'	string	(default "$XDG_DATA_HOME/nvim/undo//")
+'undodir' 'udir'	string	(default "$XDG_STATE_HOME/nvim/undo//")
 			global
 	List of directory names for undo files, separated with commas.
 	See 'backupdir' for details of the format.
@@ -6786,7 +6789,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	displayed when 'verbosefile' is set.
 
 						*'viewdir'* *'vdir'*
-'viewdir' 'vdir'	string	(default: "$XDG_DATA_HOME/nvim/view//")
+'viewdir' 'vdir'	string	(default: "$XDG_STATE_HOME/nvim/view//")
 			global
 	Name of the directory where to store files for |:mkview|.
 	This option cannot be set from a |modeline| or in the |sandbox|, for

runtime/doc/starting.txt

@@ -1044,8 +1044,8 @@ even if other entries (with known name/type/etc) are merged. |shada-merging|
 SHADA FILE NAME						*shada-file-name*
 
 - Default name of the |shada| file is:
-      Unix:     "$XDG_DATA_HOME/nvim/shada/main.shada"
+      Unix:     "$XDG_STATE_HOME/nvim/shada/main.shada"
-      Windows:  "$XDG_DATA_HOME/nvim-data/shada/main.shada"
+      Windows:  "$XDG_STATE_HOME/nvim-data/shada/main.shada"
   See also |base-directories|.
 - To choose a different file name you can use:
     - The "n" flag in the 'shada' option.
@@ -1135,7 +1135,7 @@ running) you have additional options:
 			When you get error "E929: All .tmp.X files exist,
 			cannot write ShaDa file!" check that no old temp files
 			were left behind (e.g.
-			~/.local/share/nvim/shada/main.shada.tmp*).
+			~/.local/state/nvim/shada/main.shada.tmp*).
 
 			Note: Executing :wshada will reset all |'quote| marks.
 
@@ -1329,8 +1329,8 @@ paths.
 						*base-directories* *xdg*
 The "base" (root) directories conform to the XDG Base Directory Specification.
 https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
-The $XDG_CONFIG_HOME and $XDG_DATA_HOME environment variables are used if they
+The $XDG_CONFIG_HOME, $XDG_DATA_HOME and $XDG_STATE_HOME environment variables
-exist, otherwise default values (listed below) are used.
+are used if they exist, otherwise default values (listed below) are used.
 
 CONFIG DIRECTORY (DEFAULT) ~
                   *$XDG_CONFIG_HOME*            Nvim: stdpath("config")
@@ -1342,6 +1342,11 @@ DATA DIRECTORY (DEFAULT) ~
     Unix:         ~/.local/share              ~/.local/share/nvim
     Windows:      ~/AppData/Local             ~/AppData/Local/nvim-data
 
+STATE DIRECTORY (DEFAULT) ~
+                  *$XDG_STATE_HOME*             Nvim: stdpath("state")
+    Unix:         ~/.local/state              ~/.local/state/nvim
+    Windows:      ~/AppData/Local             ~/AppData/Local/nvim-data
+
 Note: Throughout the user manual these defaults are used as placeholders, e.g.
 "~/.config" is understood to mean "$XDG_CONFIG_HOME or ~/.config".
 
@@ -1349,7 +1354,7 @@ LOG FILE					*$NVIM_LOG_FILE*
 Besides 'debug' and 'verbose', Nvim keeps a general log file for internal
 debugging, plugins and RPC clients. >
 	:echo $NVIM_LOG_FILE
-By default, the file is located at stdpath('cache')/log unless that path 
+By default, the file is located at stdpath('log')/log unless that path
 is inaccessible or if $NVIM_LOG_FILE was set before |startup|.
 
 

runtime/doc/usr_21.txt

@@ -352,12 +352,12 @@ another session.
 this yourself then.  Example: >
 
 	:mksession! ~/.config/nvim/secret.vim
-	:wshada! ~/.local/share/nvim/shada/secret.shada
+	:wshada! ~/.local/state/nvim/shada/secret.shada
 
 And to restore this again: >
 
 	:source ~/.config/nvim/secret.vim
-	:rshada! ~/.local/share/nvim/shada/secret.shada
+	:rshada! ~/.local/state/nvim/shada/secret.shada
 
 ==============================================================================
 *21.5*	Views

runtime/doc/vim_diff.txt

@@ -17,7 +17,7 @@ centralized reference of the differences.
 
 - Use `$XDG_CONFIG_HOME/nvim/init.vim` instead of `.vimrc` for your |config|.
 - Use `$XDG_CONFIG_HOME/nvim` instead of `.vim` to store configuration files.
-- Use `$XDG_DATA_HOME/nvim/shada/main.shada` instead of `.viminfo` for persistent
+- Use `$XDG_STATE_HOME/nvim/shada/main.shada` instead of `.viminfo` for persistent
   session information.  |shada|
 
 ==============================================================================
@@ -32,12 +32,12 @@ centralized reference of the differences.
 - 'autoread' is enabled
 - 'background' defaults to "dark" (unless set automatically by the terminal/UI)
 - 'backspace' defaults to "indent,eol,start"
-- 'backupdir' defaults to .,~/.local/share/nvim/backup// (|xdg|), auto-created
+- 'backupdir' defaults to .,~/.local/state/nvim/backup// (|xdg|), auto-created
 - 'belloff' defaults to "all"
 - 'compatible' is always disabled
 - 'complete' excludes "i"
 - 'cscopeverbose' is enabled
-- 'directory' defaults to ~/.local/share/nvim/swap// (|xdg|), auto-created
+- 'directory' defaults to ~/.local/state/nvim/swap// (|xdg|), auto-created
 - 'display' defaults to "lastline,msgsep"
 - 'encoding' is UTF-8 (cf. 'fileencoding' for file-content encoding)
 - 'fillchars' defaults (in effect) to "vert:│,fold:·,sep:│"
@@ -65,7 +65,7 @@ centralized reference of the differences.
 - 'tags' defaults to "./tags;,tags"
 - 'ttimeoutlen' defaults to 50
 - 'ttyfast' is always set
-- 'undodir' defaults to ~/.local/share/nvim/undo// (|xdg|), auto-created
+- 'undodir' defaults to ~/.local/state/nvim/undo// (|xdg|), auto-created
 - 'viewoptions' includes "unix,slash", excludes "options"
 - 'viminfo' includes "!"
 - 'wildmenu' is enabled

runtime/lua/vim/lsp/log.lua

@@ -25,12 +25,12 @@ do
   local function path_join(...)
     return table.concat(vim.tbl_flatten({ ... }), path_sep)
   end
-  local logfilename = path_join(vim.fn.stdpath('cache'), 'lsp.log')
+  local logfilename = path_join(vim.fn.stdpath('log'), 'lsp.log')
 
   -- TODO: Ideally the directory should be created in open_logfile(), right
   -- before opening the log file, but open_logfile() can be called from libuv
   -- callbacks, where using fn.mkdir() is not allowed.
-  vim.fn.mkdir(vim.fn.stdpath('cache'), 'p')
+  vim.fn.mkdir(vim.fn.stdpath('log'), 'p')
 
   --- Returns the log filename.
   ---@returns (string) log filename

src/nvim/README.md

@@ -38,7 +38,7 @@ alternate file (e.g. stderr) use `LOG_CALLSTACK_TO_FILE(FILE*)`. Requires
 Many log messages have a shared prefix, such as "UI" or "RPC". Use the shell to
 filter the log, e.g. at DEBUG level you might want to exclude UI messages:
 
-    tail -F ~/.cache/nvim/log | cat -v | stdbuf -o0 grep -v UI | stdbuf -o0 tee -a log
+    tail -F ~/.local/state/nvim/log | cat -v | stdbuf -o0 grep -v UI | stdbuf -o0 tee -a log
 
 Build with ASAN
 ---------------

src/nvim/eval/funcs.c

@@ -9842,6 +9842,10 @@ static void f_stdpath(typval_T *argvars, typval_T *rettv, FunPtr fptr)
     rettv->vval.v_string = get_xdg_home(kXDGDataHome);
   } else if (strequal(p, "cache")) {
     rettv->vval.v_string = get_xdg_home(kXDGCacheHome);
+  } else if (strequal(p, "state")) {
+    rettv->vval.v_string = get_xdg_home(kXDGStateHome);
+  } else if (strequal(p, "log")) {
+    rettv->vval.v_string = get_xdg_home(kXDGStateHome);
   } else if (strequal(p, "config_dirs")) {
     get_xdg_var_list(kXDGConfigDirs, rettv);
   } else if (strequal(p, "data_dirs")) {

src/nvim/log.c

@@ -51,7 +51,7 @@ static bool log_try_create(char *fname)
 
 /// Initializes path to log file. Sets $NVIM_LOG_FILE if empty.
 ///
-/// Tries $NVIM_LOG_FILE, or falls back to $XDG_CACHE_HOME/nvim/log. Path to log
+/// Tries $NVIM_LOG_FILE, or falls back to $XDG_STATE_HOME/nvim/log. Path to log
 /// file is cached, so only the first call has effect, unless first call was not
 /// successful. Failed initialization indicates either a bug in expand_env()
 /// or both $NVIM_LOG_FILE and $HOME environment variables are undefined.
@@ -69,16 +69,16 @@ static bool log_path_init(void)
       || log_file_path[0] == '\0'
       || os_isdir((char_u *)log_file_path)
       || !log_try_create(log_file_path)) {
-    // Make kXDGCacheHome if it does not exist.
+    // Make kXDGStateHome if it does not exist.
-    char *cachehome = get_xdg_home(kXDGCacheHome);
+    char *loghome = get_xdg_home(kXDGStateHome);
     char *failed_dir = NULL;
     bool log_dir_failure = false;
-    if (!os_isdir((char_u *)cachehome)) {
+    if (!os_isdir((char_u *)loghome)) {
-      log_dir_failure = (os_mkdir_recurse(cachehome, 0700, &failed_dir) != 0);
+      log_dir_failure = (os_mkdir_recurse(loghome, 0700, &failed_dir) != 0);
     }
-    XFREE_CLEAR(cachehome);
+    XFREE_CLEAR(loghome);
     // Invalid $NVIM_LOG_FILE or failed to expand; fall back to default.
-    char *defaultpath = stdpaths_user_cache_subpath("log");
+    char *defaultpath = stdpaths_user_state_subpath("log", 0, true);
     size_t len = xstrlcpy(log_file_path, defaultpath, size);
     xfree(defaultpath);
     // Fall back to .nvimlog

src/nvim/option.c

@@ -491,17 +491,17 @@ void set_init_1(bool clean_arg)
 #endif
                      false);
 
-  char *backupdir = stdpaths_user_data_subpath("backup", 2, true);
+  char *backupdir = stdpaths_user_state_subpath("backup", 2, true);
   const size_t backupdir_len = strlen(backupdir);
   backupdir = xrealloc(backupdir, backupdir_len + 3);
   memmove(backupdir + 2, backupdir, backupdir_len + 1);
   memmove(backupdir, ".,", 2);
   set_string_default("backupdir", backupdir, true);
-  set_string_default("viewdir", stdpaths_user_data_subpath("view", 2, true),
+  set_string_default("viewdir", stdpaths_user_state_subpath("view", 2, true),
                      true);
-  set_string_default("directory", stdpaths_user_data_subpath("swap", 2, true),
+  set_string_default("directory", stdpaths_user_state_subpath("swap", 2, true),
                      true);
-  set_string_default("undodir", stdpaths_user_data_subpath("undo", 2, true),
+  set_string_default("undodir", stdpaths_user_state_subpath("undo", 2, true),
                      true);
   // Set default for &runtimepath. All necessary expansions are performed in
   // this function.

src/nvim/os/stdpaths.c

@@ -14,6 +14,7 @@ static const char *xdg_env_vars[] = {
   [kXDGConfigHome] = "XDG_CONFIG_HOME",
   [kXDGDataHome] = "XDG_DATA_HOME",
   [kXDGCacheHome] = "XDG_CACHE_HOME",
+  [kXDGStateHome] = "XDG_STATE_HOME",
   [kXDGRuntimeDir] = "XDG_RUNTIME_DIR",
   [kXDGConfigDirs] = "XDG_CONFIG_DIRS",
   [kXDGDataDirs] = "XDG_DATA_DIRS",
@@ -24,6 +25,7 @@ static const char *const xdg_defaults_env_vars[] = {
   [kXDGConfigHome] = "LOCALAPPDATA",
   [kXDGDataHome] = "LOCALAPPDATA",
   [kXDGCacheHome] = "TEMP",
+  [kXDGStateHome] = "LOCALAPPDATA",
   [kXDGRuntimeDir] = NULL,
   [kXDGConfigDirs] = NULL,
   [kXDGDataDirs] = NULL,
@@ -38,6 +40,7 @@ static const char *const xdg_defaults[] = {
   [kXDGConfigHome] = "~\\AppData\\Local",
   [kXDGDataHome] = "~\\AppData\\Local",
   [kXDGCacheHome] = "~\\AppData\\Local\\Temp",
+  [kXDGStateHome] = "~\\AppData\\Local",
   [kXDGRuntimeDir] = NULL,
   [kXDGConfigDirs] = NULL,
   [kXDGDataDirs] = NULL,
@@ -45,6 +48,7 @@ static const char *const xdg_defaults[] = {
   [kXDGConfigHome] = "~/.config",
   [kXDGDataHome] = "~/.local/share",
   [kXDGCacheHome] = "~/.cache",
+  [kXDGStateHome] = "~/.local/state",
   [kXDGRuntimeDir] = NULL,
   [kXDGConfigDirs] = "/etc/xdg/",
   [kXDGDataDirs] = "/usr/local/share/:/usr/share/",
@@ -133,15 +137,26 @@ char *stdpaths_user_conf_subpath(const char *fname)
 /// Return subpath of $XDG_DATA_HOME
 ///
 /// @param[in]  fname  New component of the path.
+///
+/// @return [allocated] `$XDG_DATA_HOME/nvim/{fname}`
+char *stdpaths_user_data_subpath(const char *fname)
+  FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL FUNC_ATTR_NONNULL_RET
+{
+  return concat_fnames_realloc(get_xdg_home(kXDGDataHome), fname, true);
+}
+
+/// Return subpath of $XDG_STATE_HOME
+///
+/// @param[in]  fname  New component of the path.
 /// @param[in]  trailing_pathseps  Amount of trailing path separators to add.
 /// @param[in]  escape_commas  If true, all commas will be escaped.
 ///
-/// @return [allocated] `$XDG_DATA_HOME/nvim/{fname}`.
+/// @return [allocated] `$XDG_STATE_HOME/nvim/{fname}`.
-char *stdpaths_user_data_subpath(const char *fname, const size_t trailing_pathseps,
+char *stdpaths_user_state_subpath(const char *fname, const size_t trailing_pathseps,
-                                 const bool escape_commas)
+                                  const bool escape_commas)
   FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL FUNC_ATTR_NONNULL_RET
 {
-  char *ret = concat_fnames_realloc(get_xdg_home(kXDGDataHome), fname, true);
+  char *ret = concat_fnames_realloc(get_xdg_home(kXDGStateHome), fname, true);
   const size_t len = strlen(ret);
   const size_t numcommas = (escape_commas ? memcnt(ret, ',', len) : 0);
   if (numcommas || trailing_pathseps) {

src/nvim/os/stdpaths_defs.h

@@ -7,6 +7,7 @@ typedef enum {
   kXDGConfigHome,  ///< XDG_CONFIG_HOME
   kXDGDataHome,    ///< XDG_DATA_HOME
   kXDGCacheHome,   ///< XDG_CACHE_HOME
+  kXDGStateHome,   ///< XDG_STATE_HOME
   kXDGRuntimeDir,  ///< XDG_RUNTIME_DIR
   kXDGConfigDirs,  ///< XDG_CONFIG_DIRS
   kXDGDataDirs,    ///< XDG_DATA_DIRS

src/nvim/shada.c

@@ -1447,7 +1447,7 @@ static const char *shada_get_default_file(void)
   FUNC_ATTR_WARN_UNUSED_RESULT
 {
   if (default_shada_file == NULL) {
-    char *shada_dir = stdpaths_user_data_subpath("shada", 0, false);
+    char *shada_dir = stdpaths_user_state_subpath("shada", 0, false);
     default_shada_file = concat_fnames_realloc(shada_dir, "main.shada", true);
   }
   return default_shada_file;

test/functional/options/defaults_spec.lua

@@ -163,7 +163,7 @@ describe('startup defaults', function()
   end)
 
   it("'shadafile' ('viminfofile')", function()
-    local env = {XDG_DATA_HOME='Xtest-userdata', XDG_CONFIG_HOME='Xtest-userconfig'}
+    local env = {XDG_DATA_HOME='Xtest-userdata', XDG_STATE_HOME='Xtest-userstate', XDG_CONFIG_HOME='Xtest-userconfig'}
     clear{args={}, args_rm={'-i'}, env=env}
     -- Default 'shadafile' is empty.
     -- This means use the default location. :help shada-file-name
@@ -178,7 +178,7 @@ describe('startup defaults', function()
     clear{args={}, args_rm={'-i'}, env=env}
     eq({ f }, eval('v:oldfiles'))
     os.remove('Xtest-foo')
-    rmdir('Xtest-userdata')
+    rmdir('Xtest-userstate')
 
     -- Handles viminfo/viminfofile as alias for shada/shadafile.
     eq('\n  shadafile=', eval('execute("set shadafile?")'))
@@ -206,7 +206,7 @@ describe('startup defaults', function()
 
   describe('$NVIM_LOG_FILE', function()
     local xdgdir = 'Xtest-startup-xdg-logpath'
-    local xdgcachedir = xdgdir..'/nvim'
+    local xdgstatedir = xdgdir..'/nvim'
     after_each(function()
       os.remove('Xtest-logpath')
       rmdir(xdgdir)
@@ -218,21 +218,21 @@ describe('startup defaults', function()
       }})
       eq('Xtest-logpath', eval('$NVIM_LOG_FILE'))
     end)
-    it('defaults to stdpath("cache")/log if empty', function()
+    it('defaults to stdpath("log")/log if empty', function()
-      eq(true, mkdir(xdgdir) and mkdir(xdgcachedir))
+      eq(true, mkdir(xdgdir) and mkdir(xdgstatedir))
       clear({env={
-        XDG_CACHE_HOME=xdgdir,
+        XDG_STATE_HOME=xdgdir,
         NVIM_LOG_FILE='',  -- Empty is invalid.
       }})
-      eq(xdgcachedir..'/log', string.gsub(eval('$NVIM_LOG_FILE'), '\\', '/'))
+      eq(xdgstatedir..'/log', string.gsub(eval('$NVIM_LOG_FILE'), '\\', '/'))
     end)
-    it('defaults to stdpath("cache")/log if invalid', function()
+    it('defaults to stdpath("log")/log if invalid', function()
-      eq(true, mkdir(xdgdir) and mkdir(xdgcachedir))
+      eq(true, mkdir(xdgdir) and mkdir(xdgstatedir))
       clear({env={
-        XDG_CACHE_HOME=xdgdir,
+        XDG_STATE_HOME=xdgdir,
         NVIM_LOG_FILE='.',  -- Any directory is invalid.
       }})
-      eq(xdgcachedir..'/log', string.gsub(eval('$NVIM_LOG_FILE'), '\\', '/'))
+      eq(xdgstatedir..'/log', string.gsub(eval('$NVIM_LOG_FILE'), '\\', '/'))
     end)
   end)
 end)
@@ -264,6 +264,7 @@ describe('XDG-based defaults', function()
         XDG_CONFIG_HOME=nil,
         XDG_DATA_HOME=nil,
         XDG_CACHE_HOME=nil,
+        XDG_STATE_HOME=nil,
         XDG_RUNTIME_DIR=nil,
         XDG_CONFIG_DIRS=nil,
         XDG_DATA_DIRS=nil,
@@ -293,6 +294,7 @@ describe('XDG-based defaults', function()
 
   local env_sep = iswin() and ';' or ':'
   local data_dir = iswin() and 'nvim-data' or 'nvim'
+  local state_dir = iswin() and 'nvim-data' or 'nvim'
   local root_path = iswin() and 'C:' or ''
 
   describe('with too long XDG variables', function()
@@ -303,6 +305,7 @@ describe('XDG-based defaults', function()
                          .. env_sep.. root_path .. ('/b'):rep(2048)
                          .. (env_sep .. root_path .. '/c'):rep(512)),
         XDG_DATA_HOME=(root_path .. ('/X'):rep(4096)),
+        XDG_STATE_HOME=(root_path .. ('/X'):rep(4096)),
         XDG_DATA_DIRS=(root_path .. ('/A'):rep(2048)
                        .. env_sep .. root_path .. ('/B'):rep(2048)
                        .. (env_sep .. root_path .. '/C'):rep(512)),
@@ -355,13 +358,13 @@ describe('XDG-based defaults', function()
           .. ',' .. root_path .. ('/a'):rep(2048) .. '/nvim/after'
           .. ',' .. root_path .. ('/x'):rep(4096) .. '/nvim/after'
       ):gsub('\\', '/')), (meths.get_option('runtimepath')):gsub('\\', '/'))
-      eq('.,' .. root_path .. ('/X'):rep(4096).. '/' .. data_dir .. '/backup//',
+      eq('.,' .. root_path .. ('/X'):rep(4096).. '/' .. state_dir .. '/backup//',
          (meths.get_option('backupdir'):gsub('\\', '/')))
-      eq(root_path .. ('/X'):rep(4096) .. '/' .. data_dir .. '/swap//',
+      eq(root_path .. ('/X'):rep(4096) .. '/' .. state_dir .. '/swap//',
          (meths.get_option('directory')):gsub('\\', '/'))
-      eq(root_path .. ('/X'):rep(4096) .. '/' .. data_dir .. '/undo//',
+      eq(root_path .. ('/X'):rep(4096) .. '/' .. state_dir .. '/undo//',
          (meths.get_option('undodir')):gsub('\\', '/'))
-      eq(root_path .. ('/X'):rep(4096) .. '/'  ..  data_dir .. '/view//',
+      eq(root_path .. ('/X'):rep(4096) .. '/'  ..  state_dir .. '/view//',
          (meths.get_option('viewdir')):gsub('\\', '/'))
     end)
   end)
@@ -372,6 +375,7 @@ describe('XDG-based defaults', function()
         XDG_CONFIG_HOME='$XDG_DATA_HOME',
         XDG_CONFIG_DIRS='$XDG_DATA_DIRS',
         XDG_DATA_HOME='$XDG_CONFIG_HOME',
+        XDG_STATE_HOME='$XDG_CONFIG_HOME',
         XDG_DATA_DIRS='$XDG_CONFIG_DIRS',
       }})
     end)
@@ -405,13 +409,13 @@ describe('XDG-based defaults', function()
           .. ',$XDG_DATA_DIRS/nvim/after'
           .. ',$XDG_DATA_HOME/nvim/after'
       ):gsub('\\', '/')), (meths.get_option('runtimepath')):gsub('\\', '/'))
-      eq(('.,$XDG_CONFIG_HOME/' .. data_dir .. '/backup//'),
+      eq(('.,$XDG_CONFIG_HOME/' .. state_dir .. '/backup//'),
           meths.get_option('backupdir'):gsub('\\', '/'))
-      eq(('$XDG_CONFIG_HOME/' .. data_dir .. '/swap//'),
+      eq(('$XDG_CONFIG_HOME/' .. state_dir .. '/swap//'),
           meths.get_option('directory'):gsub('\\', '/'))
-      eq(('$XDG_CONFIG_HOME/' .. data_dir .. '/undo//'),
+      eq(('$XDG_CONFIG_HOME/' .. state_dir .. '/undo//'),
           meths.get_option('undodir'):gsub('\\', '/'))
-      eq(('$XDG_CONFIG_HOME/' .. data_dir .. '/view//'),
+      eq(('$XDG_CONFIG_HOME/' .. state_dir .. '/view//'),
           meths.get_option('viewdir'):gsub('\\', '/'))
       meths.command('set all&')
       eq(('$XDG_DATA_HOME/nvim'
@@ -425,13 +429,13 @@ describe('XDG-based defaults', function()
           .. ',$XDG_DATA_DIRS/nvim/after'
           .. ',$XDG_DATA_HOME/nvim/after'
       ):gsub('\\', '/'), (meths.get_option('runtimepath')):gsub('\\', '/'))
-      eq(('.,$XDG_CONFIG_HOME/' .. data_dir .. '/backup//'),
+      eq(('.,$XDG_CONFIG_HOME/' .. state_dir .. '/backup//'),
           meths.get_option('backupdir'):gsub('\\', '/'))
-      eq(('$XDG_CONFIG_HOME/' .. data_dir .. '/swap//'),
+      eq(('$XDG_CONFIG_HOME/' .. state_dir .. '/swap//'),
           meths.get_option('directory'):gsub('\\', '/'))
-      eq(('$XDG_CONFIG_HOME/' .. data_dir .. '/undo//'),
+      eq(('$XDG_CONFIG_HOME/' .. state_dir .. '/undo//'),
           meths.get_option('undodir'):gsub('\\', '/'))
-      eq(('$XDG_CONFIG_HOME/' .. data_dir .. '/view//'),
+      eq(('$XDG_CONFIG_HOME/' .. state_dir .. '/view//'),
           meths.get_option('viewdir'):gsub('\\', '/'))
     end)
   end)
@@ -442,6 +446,7 @@ describe('XDG-based defaults', function()
         XDG_CONFIG_HOME=', , ,',
         XDG_CONFIG_DIRS=',-,-,' .. env_sep .. '-,-,-',
         XDG_DATA_HOME=',=,=,',
+        XDG_STATE_HOME=',=,=,',
         XDG_DATA_DIRS=',≡,≡,' .. env_sep .. '≡,≡,≡',
       }})
     end)
@@ -484,13 +489,13 @@ describe('XDG-based defaults', function()
           .. ',\\,-\\,-\\,' .. path_sep ..'nvim' .. path_sep ..'after'
           .. ',\\, \\, \\,' .. path_sep ..'nvim' .. path_sep ..'after'
       ), meths.get_option('runtimepath'))
-      eq('.,\\,=\\,=\\,' .. path_sep .. data_dir .. '' .. path_sep ..'backup' .. (path_sep):rep(2),
+      eq('.,\\,=\\,=\\,' .. path_sep .. state_dir .. '' .. path_sep ..'backup' .. (path_sep):rep(2),
           meths.get_option('backupdir'))
-      eq('\\,=\\,=\\,' .. path_sep ..'' .. data_dir .. '' .. path_sep ..'swap' .. (path_sep):rep(2),
+      eq('\\,=\\,=\\,' .. path_sep ..'' .. state_dir .. '' .. path_sep ..'swap' .. (path_sep):rep(2),
           meths.get_option('directory'))
-      eq('\\,=\\,=\\,' .. path_sep ..'' .. data_dir .. '' .. path_sep ..'undo' .. (path_sep):rep(2),
+      eq('\\,=\\,=\\,' .. path_sep ..'' .. state_dir .. '' .. path_sep ..'undo' .. (path_sep):rep(2),
           meths.get_option('undodir'))
-      eq('\\,=\\,=\\,' .. path_sep ..'' .. data_dir .. '' .. path_sep ..'view' .. (path_sep):rep(2),
+      eq('\\,=\\,=\\,' .. path_sep ..'' .. state_dir .. '' .. path_sep ..'view' .. (path_sep):rep(2),
           meths.get_option('viewdir'))
     end)
   end)
@@ -499,8 +504,9 @@ end)
 
 describe('stdpath()', function()
   -- Windows appends 'nvim-data' instead of just 'nvim' to prevent collisions
-  -- due to XDG_CONFIG_HOME and XDG_DATA_HOME being the same.
+  -- due to XDG_CONFIG_HOME, XDG_DATA_HOME and XDG_STATE_HOME being the same.
   local datadir = iswin() and 'nvim-data' or 'nvim'
+  local statedir = iswin() and 'nvim-data' or 'nvim'
   local env_sep = iswin() and ';' or ':'
 
   it('acceptance', function()
@@ -509,6 +515,7 @@ describe('stdpath()', function()
     eq('nvim', funcs.fnamemodify(funcs.stdpath('cache'), ':t'))
     eq('nvim', funcs.fnamemodify(funcs.stdpath('config'), ':t'))
     eq(datadir, funcs.fnamemodify(funcs.stdpath('data'), ':t'))
+    eq(statedir, funcs.fnamemodify(funcs.stdpath('state'), ':t'))
     eq('table', type(funcs.stdpath('config_dirs')))
     eq('table', type(funcs.stdpath('data_dirs')))
     assert_alive()  -- Check for crash. #8393
@@ -582,6 +589,39 @@ describe('stdpath()', function()
       end)
     end)
 
+    describe('with "state"' , function ()
+      it('knows XDG_STATE_HOME', function()
+        clear({env={
+          XDG_STATE_HOME=alter_slashes('/home/docwhat/.local'),
+        }})
+        eq(alter_slashes('/home/docwhat/.local/'..statedir), funcs.stdpath('state'))
+      end)
+
+      it('handles changes during runtime', function()
+        clear({env={
+          XDG_STATE_HOME=alter_slashes('/home/original'),
+        }})
+        eq(alter_slashes('/home/original/'..statedir), funcs.stdpath('state'))
+        command("let $XDG_STATE_HOME='"..alter_slashes('/home/new').."'")
+        eq(alter_slashes('/home/new/'..statedir), funcs.stdpath('state'))
+      end)
+
+      it("doesn't expand $VARIABLES", function()
+        clear({env={
+          XDG_STATE_HOME='$VARIABLES',
+          VARIABLES='this-should-not-happen',
+        }})
+        eq(alter_slashes('$VARIABLES/'..statedir), funcs.stdpath('state'))
+      end)
+
+      it("doesn't expand ~/", function()
+        clear({env={
+          XDG_STATE_HOME=alter_slashes('~/frobnitz'),
+        }})
+        eq(alter_slashes('~/frobnitz/'..statedir), funcs.stdpath('state'))
+      end)
+    end)
+
     describe('with "cache"' , function ()
       it('knows XDG_CACHE_HOME', function()
         clear({env={