Add optional return binding

Still experimental

3 files changed, 52 insertions, 3 deletions

diff --git a/doc/changelog.org b/doc/changelog.org
index 0911c2b..9010b26 100644
--- a/doc/changelog.org
+++ b/doc/changelog.org
@@ -2,6 +2,7 @@
   - Make =dw= realign tags. Make =dd= renumber lists.
   - Simplify implementation of `evil-org-open-above/below`.
     - Only continue item lists on first line.
+  - Add =return= keytheme.
 * Version 0.9
   - Make =I= / =A= ignore ellipses on heading. Also make them respect =org-special-ctrl-a/e=.
   - Make it possible for =<= and =>= (renamed to evil-org-</>) to move table columns.
diff --git a/doc/keythemes.org b/doc/keythemes.org
index a2d2ea3..cccb15b 100644
--- a/doc/keythemes.org
+++ b/doc/keythemes.org
@@ -63,6 +63,29 @@
                      (kbd "<") 'org-meta-left)
     #+end_src
     Or enable the additional key binding theme and use =M-h= and =M-l.=
+    
+** Return
+   Experimental function bound to =RET=.
+   Disabled by default. If enabled, it's active in insert and emacs state.
+
+   Depending on context, it performs one of the following actions:
+   - When on an empty item or table row, abort or split the item list or table.
+   - When on a non-empty item or table row, continue the item list or table.
+   - Otherwise, insert a newline and indent.
+
+   This makes =RET= more consistent with =evil-org-open-above/below= (which are bound to =o= and =O= by default).
+   
+   |-------+-----------------|
+   | key   | function        |
+   |-------+-----------------|
+   | =RET= | evil-org-return |
+   |-------+-----------------|
+   
+   Based on the following earlier work:
+   - https://github.com/calvinwyoung/org-autolist
+   - http://kitchingroup.cheme.cmu.edu/blog/2017/04/09/A-better-return-in-org-mode/
+
+   * The cases in which =RET= should behave special can be controlled using =evil-org-special-o/O=. By default it's set to ~'(table-row item)~.
 
 ** Navigation
    If you don't want to use =h/j/k/l,= you can customize =evil-org-movement-bindings=.
diff --git a/evil-org.el b/evil-org.el
index fc01479..171eda2 100644
--- a/evil-org.el
+++ b/evil-org.el
@@ -59,6 +59,7 @@ arguments."
   :group 'evil-org
   :type '(set (const navigation)
               (const insert)
+              (const return)
               (const textobjects)
               (const rsi)
               (const additional)
@@ -94,8 +95,6 @@ By default, o and O are bound to ‘evil-org-open-above’ and ‘evil-org-open-
   :group 'evil-org
   :type 'boolean)
 
-;; Constants
-
 ;;; Variable declarations
 (defvar browse-url-generic-program)
 (defvar browse-url-generic-args)
@@ -269,7 +268,30 @@ Passing in any prefix argument, executes the command without special behavior."
          (evil-insert nil))
         ((evil-open-above count))))
 
-  (evil-insert nil))
+(defun evil-org-return (arg)
+  "Like `org-return', but continues items and tables like `evil-open-below'.
+Pressing return twice cancels the continuation of the itemlist or table.
+If ARG is set it will not cancel the continuation.
+The behavior of this function can be controlled using `evil-org-special-o/O’."
+  (interactive "P")
+  (cond ((and (not arg) (evil-org--empty-element-p))
+         (delete-region (line-beginning-position) (line-end-position)))
+        ((eolp)
+         (call-interactively #'evil-org-open-below))
+        ('otherwise
+         (call-interactively #'org-return-indent))))
+
+(defun evil-org--empty-element-p ()
+  "Return if pointer is on an empty element."
+  (cond ((org-at-table-p)
+         (let* ((rows (cl-remove 'hline (org-table-to-lisp)))
+                (row (nth (1- (org-table-current-line)) rows)))
+           (cl-every 'string-empty-p row)))
+        ((org-at-item-p)
+         (let ((e (org-element-at-point)))
+           (or (not (org-element-property :contents-begin e))
+               (> (org-element-property :contents-begin e)
+                  (line-end-position)))))))
 
 (defmacro evil-org-define-eol-command (cmd)
   "Return a function that executes CMD at eol and then enters insert state.
@@ -698,6 +720,9 @@ Optional argument THEME list of themes. See evil-org-keytheme for a list of valu
     (evil-org--populate-base-bindings)
     (when (memq 'navigation theme) (evil-org--populate-navigation-bindings))
     (when (memq 'insert theme) (evil-org--populate-insert-bindings))
+    (when (memq 'return theme)
+      (evil-define-key 'insert evil-org-mode-map (kbd "RET") 'evil-org-return)
+      (define-key evil-org-mode-map (kbd "RET") 'evil-org-return))
     (when (memq 'textobjects theme) (evil-org--populate-textobjects-bindings))
     (when (memq 'rsi theme) (evil-org--populate-rsi-bindings))
     (when (memq 'additional theme) (evil-org--populate-additional-bindings))