As of Emacs 26.3 on OSX is appears back-directory-alist is
ignored. Auto-save files are no longer going to a tmpdir but are always
saved in the current directory.

I verified this by starting emacs with --no-init-file and setting the
backup-directory-alist manually.

-Brett


In GNU Emacs 26.3 (build 1, x86_64-apple-darwin18.2.0, NS appkit-1671.20
Version 10.14.3 (Build 18D109))
 of 2019-09-02 built on builder10-14.porkrind.org
Windowing system distributor 'Apple', version 10.3.1671
Recent messages:
uncompressing files.el.gz...done
Wrote /Users/brett/.emacs.d/.emacs.desktop.lock
Desktop: 1 frame, 4 buffers restored.
Turning on magit-auto-revert-mode...done (0.352s, 10 buffers checked)
For information about GNU Emacs and the GNU system, type C-h C-a.
Loading /Users/brett/.emacs.d/recentf...done
Cleaning up the recentf list...done (0 removed)
package.json has auto save data; consider M-x recover-this-file
Undo!
C-M-g is undefined

Configured using:
 'configure --with-ns '--enable-locallisppath=/Library/Application
 Support/Emacs/${version}/site-lisp:/Library/Application
 Support/Emacs/site-lisp' --with-modules'

Configured features:
NOTIFY ACL GNUTLS LIBXML2 ZLIB TOOLKIT_SCROLL_BARS NS MODULES THREADS

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Emacs-Lisp

Minor modes in effect:
  recentf-mode: t
  global-anzu-mode: t
  anzu-mode: t
  helm-mode: t
  yas-global-mode: t
  yas-minor-mode: t
  global-magit-file-mode: t
  magit-file-mode: t
  diff-auto-refine-mode: t
  magit-auto-revert-mode: t
  auto-revert-mode: t
  global-git-commit-mode: t
  async-bytecomp-package-mode: t
  shell-dirtrack-mode: t
  flyspell-mode: t
  helm-autoresize-mode: t
  helm--remap-mouse-mode: t
  flycheck-color-mode-line-mode: t
  global-flycheck-mode: t
  flycheck-mode: t
  global-auto-complete-mode: t
  auto-complete-mode: t
  show-paren-mode: t
  save-place-mode: t
  desktop-save-mode: t
  global-whitespace-mode: t
  delete-selection-mode: t
  global-hl-line-mode: t
  electric-pair-mode: t
  savehist-mode: t
  override-global-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug sendmail helm-command helm-elisp
helm-eval edebug recentf tree-widget wid-edit ido helm-x-files
helm-for-files helm-bookmark helm-adaptive helm-info magit-bookmark
bookmark pp winner helm-external helm-net browse-url xml jka-compr js
sgml-mode dom pcase vc-git init tramp tramp-compat tramp-loaddefs
trampver parse-time midnight shell-pop term ehelp anzu helm-mode
helm-files helm-buffers helm-occur helm-tags helm-locate helm-grep
helm-regexp helm-utils helm-help helm-types helm-config helm-easymenu
yasnippet powerline powerline-separators color powerline-themes
magit-submodule magit-obsolete magit-blame magit-stash magit-reflog
magit-bisect magit-push magit-pull magit-fetch magit-clone magit-remote
magit-commit magit-sequence magit-notes magit-worktree magit-tag
magit-merge magit-branch magit-reset magit-files magit-refs magit-status
magit magit-repos magit-apply magit-wip magit-log which-func magit-diff
smerge-mode diff-mode magit-core magit-autorevert autorevert filenotify
magit-margin magit-transient magit-process magit-mode git-commit
transient magit-git magit-section magit-utils crm log-edit message rmc
puny dired dired-loaddefs format-spec rfc822 mml mml-sec epa derived epg
gnus-util rmail rmail-loaddefs mm-decode mm-bodies mm-encode mail-parse
rfc2231 rfc2047 rfc2045 mm-util ietf-drums mail-prsvr mailabbrev
mail-utils gmm-utils mailheader pcvs-util with-editor async-bytecomp
shell pcomplete server flycheck-gometalinter go-guru go-mode url
url-proxy url-privacy url-expand url-methods url-history url-cookie
url-domsuf url-util mailcap find-file ffap go-autocomplete php-mode
mode-local imenu speedbar sb-image ezimage dframe add-log cc-langs
cc-mode cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine
cc-vars cc-defs php-face php php-project ac-ispell flyspell-lazy
helm-flyspell flyspell ispell helm helm-source eieio-compat
helm-multi-match helm-lib async flycheck-haskell flycheck-pos-tip
pos-tip flycheck-color-mode-line face-remap flycheck json map find-func
subr-x dash haskell-mode haskell-cabal haskell-utils haskell-font-lock
haskell-indentation haskell-string haskell-sort-imports haskell-lexeme
rx haskell-align-imports haskell-complete-module haskell-ghc-support
noutline outline flymake-proc flymake warnings thingatpt etags xref
project compile comint ring dabbrev ansi-color haskell-customize
auto-complete-config auto-complete edmacro kmacro popup
twilight-anti-bright-theme better-defaults paren saveplace
exec-path-from-shell cl-extra help-mode desktop frameset disp-table
whitespace delsel hl-line elec-pair play-sound cl advice savehist
use-package use-package-ensure use-package-delight use-package-diminish
use-package-bind-key bind-key easy-mmode use-package-core finder-inf
info package easymenu epg-config url-handlers url-parse auth-source
cl-seq eieio eieio-core cl-macs eieio-loaddefs password-cache url-vars
seq byte-opt gv bytecomp byte-compile cconv cl-loaddefs cl-lib time-date
tooltip eldoc electric uniquify ediff-hook vc-hooks lisp-float-type
mwheel term/ns-win ns-win ucs-normalize mule-util term/common-win
tool-bar dnd fontset image regexp-opt fringe tabulated-list replace
newcomment text-mode elisp-mode lisp-mode prog-mode register page
menu-bar rfn-eshadow isearch timer select scroll-bar mouse jit-lock
font-lock syntax facemenu font-core term/tty-colors frame cl-generic
cham georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese composite charscript charprop
case-table epa-hook jka-cmpr-hook help simple abbrev obarray minibuffer
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote threads kqueue cocoa ns
multi-tty make-network-process emacs)

Memory information:
((conses 16 592818 47387)
 (symbols 48 48646 3)
 (miscs 40 396 611)
 (strings 32 152919 4251)
 (string-bytes 1 4530554)
 (vectors 16 78826)
 (vector-slots 8 1243801 37730)
 (floats 8 351 441)
 (intervals 56 1737 425)
 (buffers 992 19))