use espresso-mode's indent with js2-mode

emacs

@@ -203,12 +203,71 @@
 ;; javascript
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
+;; js-mode (espresso)
+;; Espresso mode has sane indenting so we use that.
+(setq js-indent-level 4)
+
+;; Customize JS2
+(setq js2-basic-offset 4)
+(setq js2-cleanup-whitespace t)
+
 (autoload 'js2-mode "js2-mode" nil t)
 (add-to-list 'auto-mode-alist '("\\.js$" . js2-mode))
 (add-to-list 'auto-mode-alist '("Jakefile$" . js2-mode))
-(add-hook 'js2-mode-hook '(lambda ()
-			    (local-set-key "\C-m" 'newline)
-			     (setq indent-tabs-mode nil)))
+
+
+;; Custom indentation function since JS2 indenting is terrible.
+;; Uses js-mode's (espresso-mode) indentation semantics.
+;;
+;; Based on: http://mihai.bazon.net/projects/editing-javascript-with-emacs-js2-mode
+;; (Thanks!)
+(defun my-js2-indent-function ()
+  (interactive)
+  (save-restriction
+    (widen)
+    (let* ((inhibit-point-motion-hooks t)
+           (parse-status (save-excursion (syntax-ppss (point-at-bol))))
+           (offset (- (current-column) (current-indentation)))
+           (indentation (js--proper-indentation parse-status))
+           node)
+
+      (save-excursion
+
+        ;; I like to indent case and labels to half of the tab width
+        (back-to-indentation)
+        (if (looking-at "case\\s-")
+            (setq indentation (+ indentation (/ js-indent-level 2))))
+
+        ;; consecutive declarations in a var statement are nice if
+        ;; properly aligned, i.e:
+        ;;
+        ;; var foo = "bar",
+        ;;     bar = "foo";
+        (setq node (js2-node-at-point))
+        (when (and node
+                   (= js2-NAME (js2-node-type node))
+                   (= js2-VAR (js2-node-type (js2-node-parent node))))
+          (setq indentation (+ 4 indentation))))
+
+      (indent-line-to indentation)
+      (when (> offset 0) (forward-char offset)))))
+
+(defun my-js2-mode-hook ()
+  (if (not (boundp 'js--proper-indentation))
+      (progn (js-mode)
+             (remove-hook 'js2-mode-hook 'my-js2-mode-hook)
+             (js2-mode)
+             (add-hook 'js2-mode-hook 'my-js2-mode-hook)))
+  (set (make-local-variable 'indent-line-function) 'my-js2-indent-function)
+  (define-key js2-mode-map [(return)] 'newline-and-indent)
+  (define-key js2-mode-map [(backspace)] 'c-electric-backspace)
+  (define-key js2-mode-map [(control d)] 'c-electric-delete-forward)
+  (local-set-key "\C-m" 'newline)
+  (setq indent-tabs-mode nil)
+  (message "JS2 mode hook ran."))
+
+;; Add the hook so this is all loaded when JS2-mode is loaded
+(add-hook 'js2-mode-hook 'my-js2-mode-hook)
 
 (autoload #'espresso-mode "espresso" "Start espresso-mode" t)
 ;;(add-to-list 'auto-mode-alist '("\\.js$" . espresso-mode))