Use general.el to provide multiple leader key in evil-mode

General.el "provides a more convenient way to bind keys in emacs for both evil and non-evil users".

I have been using it for more than one month without any issue. I prefer general.el to evil-leader because I need both comma and space key as leader key.

Minimum setup is simple,

(require 'general)
(general-evil-setup t)
(nvmap :prefix ","
       "bb" 'back-to-previous-buffer
       "ww" 'save-buffer
       "oo" 'compile)

;; all keywords arguments are still supported
(nvmap :prefix "SPC"
       ; save windows layout
       "ss" 'wg-create-workgroup
       ;; load windows layout
       "ll" 'my-wg-switch-workgroup)

My real world setup is more complicated.

Use ivy to open recent directories

The recent directories include parent directories of opened files in Emacs and the directories accessed in Bash shell.

I used fasd to get the list of directories in shell. Fasd "offers quick access to files and directories for POSIX shells".

Here is my setup,

(require 'ivy) ; swiper 7.0+ should be installed

(defun counsel-goto-recent-directory ()
  "Open recent directory with dired"
  (interactive)
  (unless recentf-mode (recentf-mode 1))
  (let ((collection
         (delete-dups
          (append (mapcar 'file-name-directory recentf-list)
                  ;; fasd history
                  (if (executable-find "fasd")
                      (split-string (shell-command-to-string "fasd -ld") "\n" t))))))
    (ivy-read "directories:" collection :action 'dired)))

Screenshot:

ivy-recent-directory-nq8.png

Emacs vs Sublime Text on Salesforce development

Our client decided to move their legacy system to a cloud platform called salesforce.com. So I got a chance to investigate how to deploy code to the salesforce server inside Emacs and Sublime Text.

Salesforce provides a migration tool to deploy everything from the scratch which takes about 2 minutes. Basically makes it impossbile to be integrated with text editors.

Luckily, there is Force.com CLI which can upload single file in a few seconds. Both Sublime Text and Emacs use this tool.

1 Sublime Text

You need install sublime text plugin mavensmate. After installation, you need click Login menu at least once. Then when you save the code file, it's automatically deployed to the server.

For some reason, the logged in session will timeout after a couple minutes. So you need re-login. Sometimes deployment will fail, you could click the Fetch menu and fill in the component name into the popup window to confirm the fetch. Fetching will re-activate upload ability.

Mavensmate is actually just GUI wrapper of Force.com CLI,

  • When you click login, the command force login is executed
  • When saving file, force aura push or force push is executed
  • When fetching, force fetch is executed

2 Emacs

In Sublime Text I have to re-login and fetch from time to time. That get me distracted. I prefer executing only one commmand to upload the file in editing. That command should be always successful.

My solution is to combine "login/fetch/push" commnands into one liner which is stored in a file local variable compile-command. So when I execute M-x compile, the commands "login/fetch/push" in compile-command will all be executed sequentially. So I don't need care about login and fetch things any more.

Here is my setup,

(defun my-setup-develop-environment ()
  (interactive)
  (let (ffip-project-root)
    (setq ffip-project-root "~/projects/my-salesforce-project1")

    (when (memq major-mode '(web-mode js-mode js2-mode))
      (setq-local compile-command
                  (cond
                   ;; lightning controller javascript file
                   ((string-match "Controller\.js$" (buffer-file-name))
                    (format "force login -i=test -u=username@salesforce.com -p=password1; cd %s && cp %s %s && force fetch -t Aura -n %s -d %s && mv %s %s && force aura push -f %s"
                            ffip-project-root
                            (buffer-file-name) (concat (buffer-file-name) ".bak")
                            (replace-regexp-in-string "Controller" "" (file-name-base (buffer-file-name)))
                            ffip-project-root
                            (concat (buffer-file-name) ".bak") (buffer-file-name)
                            (buffer-file-name)))
                   ;; ant build
                   ((string-match "build\.xml$" (buffer-file-name))
                    (format "cd %s && ant deployCode" ffip-project-root))
                   ;; lightning html view
                   ((string-match "\.cmp$" (buffer-file-name))
                    (format "force login -i=test -u=username@salesforce.com -p=password1; cd %s && force aura push -f %s"
                            ffip-project-root
                            (buffer-file-name)))
                   ;; other salesforce pages
                   (t
                    (format "force login -i=test -u=username@salesforce.com -p=password1; cd %s && force push -f %s"
                            ffip-project-root
                            (buffer-file-name)))
                   )))
    ))

;; I use web-mode for html/xml
(add-hook 'web-mode-hook 'my-setup-develop-environment)
;; I use js2-mode for javascript
(add-hook 'js2-mode-hook 'my-setup-develop-environment)

How to be extremely efficient in Emacs

All you need to do is using keyfreq to measure how many time you execute commands.

The frequently used commands should be assigned efficient key bindings.

But you need exclude already optimized commands or commands which cannot be optimized before starting keyfreq.

For example, commands like next-line/previous-line/forward-char/backward-char could be excluded by tweaking variable keyfreq-excluded-commands.

The minimum keyfreq setup,

(require 'keyfreq)
(setq keyfreq-excluded-commands
      '(self-insert-command
        abort-recursive-edit
        forward-char
        backward-char
        previous-line
        next-line))
(keyfreq-mode 1)
(keyfreq-autosave-mode 1)

My actual keyfreq setup is more complicated.

Below is the eight month keyfreq data of my office computer,

Times Percentage Command Key
4967 12.00% evilmi-jump-items %
2892 6.99% compile , o o
2178 5.26% find-file-in-project-by-selected , k k
1953 4.72% copy-to-x-clipboard , a a
1566 3.78% paste-from-x-clipboard , z z
1227 2.96% er/expand-region , x x
897 2.17% evil-repeat .
866 2.09% ido-find-file , x f, C-x C-f
819 1.98% toggle-full-window , f f
815 1.97% etags-select-find-tag-at-point C-], , h t
721 1.74% back-to-previous-buffer , b b
682 1.65% split-window-vertically , x 2
539 1.30% find-function , h f, C-h C-f
494 1.19% counsel-recentf-goto , r r
397 0.96% counsel-git-grep , g g
376 0.91% delete-other-windows , x 1, C-x 1
372 0.90% evilnc-comment-or-uncomment-lines , c i
351 0.85% eval-expression , e e, M-:
326 0.79% evilmi-select-items , s i
320 0.77% paredit-doublequote  
307 0.74% evil-filepath-outer-text-object  
300 0.72% steve-ido-choose-from-recentf  
295 0.71% split-window-horizontally , x 3
283 0.68% git-add-current-file , x v a
279 0.67% winner-undo , x u, , s u, C-x 4 u
278 0.67% describe-function , h d, C-h f
278 0.67% evil-goto-mark-line '
269 0.65% ido-kill-buffer , x k, C-x k
254 0.61% evil-goto-definition g d
253 0.61% pop-tag-mark M-*
251 0.61% git-messenger:popup-message , x v b, C-x v p
246 0.59% my-goto-next-hunk , n n
237 0.57% evilnc-comment-operator , ,
235 0.57% flyspell-goto-next-error , f e, C-,
214 0.52% evil-exit-emacs-state  
212 0.51% browse-kill-ring-forward  
210 0.51% flyspell-buffer , f b
203 0.49% evil-ex-completion  
195 0.47% narrow-or-widen-dwim , x n n
173 0.42% comint-send-input  
173 0.42% beginning-of-defun , b f
170 0.41% evil-surround-region <visual-state> S
161 0.39% hippie-expand M-/
151 0.36% describe-key , h k, C-h k
149 0.36% evil-space–evil-next-visual-line SPC
139 0.34% gnus-topic-select-group  
138 0.33% js2-print-json-path , j p p
132 0.32% goto-line M-g g, M-g M-g
132 0.32% evil-avy-goto-subword-1 ;
127 0.31% ibuffer-mark-for-delete  
127 0.31% evil-inner-single-quote  
126 0.30% isearch-other-meta-char  
124 0.30% term-send-up  
118 0.29% isearch-other-control-char  
116 0.28% evil-set-marker m
115 0.28% browse-kill-ring M-y, , y y
114 0.28% counsel-git-grep-yank-line , g l
114 0.28% evil-window-down C-w j
112 0.27% evil-jump-backward C-o
108 0.26% evil-visual-block C-v
108 0.26% evil-space–evil-previous-visual-line S-SPC
107 0.26% comint-previous-input  
98 0.24% gnus-summary-exit  
98 0.24% evil-search-word-backward #
98 0.24% forward-button  
96 0.23% evil-paste-pop-next  
95 0.23% ediff-next-difference  
95 0.23% ido-imenu , i i
92 0.22% my-wg-switch-workgroup , w g g
90 0.22% counsel-git-find-file , g f
90 0.22% evilmi-delete-items , d i
87 0.21% gnus-summary-extract-mail-address  
87 0.21% cliphist-paste-item , h h
84 0.20% subword-backward-kill <C-backspace>
84 0.20% paredit-backslash  
83 0.20% my-yas-reload-all , y c r
81 0.20% pwd  
80 0.19% previous-complete-history-element  
80 0.19% wg-create-workgroup , w g t
78 0.19% evil-forward-WORD-end E
77 0.19% gnus-summary-scroll-up  
76 0.18% gnus-summary-extract-cc-and-to  
75 0.18% compile-goto-error  
73 0.18% evil-find-char-to t
72 0.17% evil-repeat-find-char  
69 0.17% evil-window-up C-w k
67 0.16% eval-last-sexp , x e, C-x C-e
66 0.16% evil-complete-next-line  
66 0.16% exchange-point-and-mark C-x C-x
63 0.15% direx:previous-item  
61 0.15% ediff-jump-to-difference  
60 0.14% diredp-next-line  
58 0.14% evilmr-replace-in-buffer , r b
58 0.14% counsel-imenu-goto , i m
56 0.14% evil-goto-mark `
55 0.13% gnus-group-unsubscribe-current-group  
55 0.13% ivy-bookmark-goto  
55 0.13% evil-filepath-inner-text-object  
54 0.13% describe-mode C-h m
54 0.13% recenter-top-bottom C-l
54 0.13% list-packages  
52 0.13% gnus-topic-mark-topic  
52 0.13% kill-line C-k, <deleteline>
51 0.12% find-and-ctags-update-all-tags-force  
50 0.12% evil-paste-before P
49 0.12% execute-extended-command <execute>, C-x RET
49 0.12% etags-select-quit  
49 0.12% evil-inner-WORD  
48 0.12% find-tag g C-]
47 0.11% diredp-previous-line  
46 0.11% paredit-close-square  
44 0.11% paredit-open-square  
44 0.11% evil-paste-last-insertion  
42 0.10% evil-inner-double-quote  
42 0.10% ivy-imenu-goto  
40 0.10% counsel-git-find-my-file , g m
39 0.09% cp-filename-of-current-buffer , f n
39 0.09% gnus-article-read-summary-keys  
39 0.09% isearch-nonincremental-exit-minibuffer  
38 0.09% sh-assignment  
38 0.09% mark-whole-buffer , x h, C-x h
38 0.09% evilmi-inner-text-object  
36 0.09% evilnc-comment-or-uncomment-paragraphs , c p, C-c p
36 0.09% evil-toggle-input-method C-\
35 0.08% org2nikola-export-subtree  
35 0.08% subword-forward M-f, ESC <right>
34 0.08% evil-open-above O
34 0.08% compose-mail C-x m
33 0.08% evil-inner-paren  
33 0.08% term-send-raw-meta  
33 0.08% evil-invert-char ~
32 0.08% evil-space–evil-repeat-find-char  
32 0.08% httpd-restart-at-default-directory , w r d
32 0.08% cp-fullpath-of-current-buffer , f p
31 0.07% evil-forward-WORD-begin W
30 0.07% sort-lines , s l
30 0.07% bmkp-w3m-jump  
30 0.07% evilnc-copy-and-comment-lines , c c, C-c c
29 0.07% toggle-company-ispell , t c i
29 0.07% top-level  
28 0.07% package-menu-mark-upgrades  
27 0.07% evil-numbers/dec-at-pt -
27 0.07% end-of-defun , e f, C-M-e
27 0.07% my-setup-develop-environment  
26 0.06% evil-paste-pop  
25 0.06% ediff-previous-difference  
25 0.06% evil-backward-WORD-begin B
25 0.06% goto-char g o, M-g c
25 0.06% w3m-close-window  
25 0.06% org-mime-htmlize  
25 0.06% gnus-group-exit  
24 0.06% git-gutter:toggle C-x C-g
23 0.06% my-gnus-group-list-subscribed-groups  
23 0.06% find-directory-in-project-by-selected , f d
23 0.06% evil-inner-curly  
22 0.05% org-edit-src-exit  
22 0.05% string-edit-at-point , s e
22 0.05% package-menu-mark-delete  
22 0.05% ido-magic-forward-char  
22 0.05% run-js , r j s
22 0.05% git-gutter-reset-to-head-parent , g s h
21 0.05% counsel-read-history  
21 0.05% rcirc-send-input  
21 0.05% gnus-undo  
21 0.05% subword-backward M-b
20 0.05% company-select-next  
20 0.05% what-cursor-position g a, g 8, C-x =
20 0.05% my-grep , q q
20 0.05% hydra-gnus-summary/body  
19 0.05% ansi-term  
19 0.05% evil-window-right C-w l
19 0.05% debugger-jump  
19 0.05% wg-switch-to-workgroup  
19 0.05% yas-abort-snippet  
19 0.05% tags-loop-continue M-,
19 0.05% swiper-the-thing , s s
18 0.04% my-wg-swich-to-workgroup  
18 0.04% org-edit-special  
17 0.04% lisp-complete-symbol  
17 0.04% my-wg-switch-to-workgroup-at-index  
17 0.04% test  
17 0.04% ediff-scroll-vertically  
16 0.04% w3m-view-previous-page  
16 0.04% evil-window-left C-w h
16 0.04% isearch-yank-kill  
16 0.04% my-goto-previous-hunk , p p
16 0.04% js-beautify , j b
16 0.04% hydra-launcher/body  
16 0.04% read-only-mode C-x C-q
16 0.04% message-send-and-exit  
16 0.04% etags-select-goto-tag  
15 0.04% evil-next-match g n
15 0.04% js2r-kill , j j k
15 0.04% string-edit-conclude  
15 0.04% delete-char  
14 0.03% gnus-summary-limit-to-author  
14 0.03% ediff-swap-buffers  

Diff regions in Emacs

CREATED: <2016-01-27>

UPDATED: <2016-04-09 Sat>

I know M-x ediff-regions-linewise.

But it's kind of too generic. I only want to view the different lines of two regions as quickly as possible.

So here is my code,

;; Diff two regions
;; Step 1: Select a region and `M-x diff-region-tag-selected-as-a'
;; Step 2: Select another region and `M-x diff-region-compare-with-b'
;; Press "q" in evil-mode or "C-c C-c" to exit the diff output buffer
(defun diff-region-format-region-boundary (b e)
  "Make sure lines are selected and B is less than E"
  (let (tmp rlt)
    ;; swap b e, make sure b < e
    (when (> b e)
      (setq tmp b)
      (setq b e)
      (set e tmp))

    ;; select lines
    (save-excursion
      ;; Another workaround for evil-visual-line bug:
      ;; In evil-mode, if we use hotkey V or `M-x evil-visual-line` to select line,
      ;; the (line-beginning-position) of the line which is after the last selected
      ;; line is always (region-end)! Don't know why.
      (if (and (> e b)
               (save-excursion (goto-char e) (= e (line-beginning-position)))
               (boundp 'evil-state) (eq evil-state 'visual))
          (setq e (1- e)))
      (goto-char b)
      (setq b (line-beginning-position))
      (goto-char e)
      (setq e (line-end-position)))
    (setq rlt (list b e))
    rlt))

(defun diff-region-exit ()
  (interactive)
  (bury-buffer "*Diff-region-output*")
  (winner-undo))

(defun diff-region-tag-selected-as-a ()
  "Select a region to compare"
  (interactive)
  (when (region-active-p)
    (let (tmp buf)
      ;; select lines
      (setq tmp (diff-region-format-region-boundary (region-beginning) (region-end)))
      (setq buf (get-buffer-create "*Diff-regionA*"))
      (save-current-buffer
        (set-buffer buf)
        (erase-buffer))
      (append-to-buffer buf (car tmp) (cadr tmp))))
  (message "Now select other region to compare and run `diff-region-compare-with-b`"))

(defun diff-region-compare-with-b ()
  "Compare current region with region selected by `diff-region-tag-selected-as-a' "
  (interactive)
  (if (region-active-p)
      (let (rlt-buf
            diff-output
            (fa (make-temp-file (expand-file-name "scor"
                                                  (or small-temporary-file-directory
                                                      temporary-file-directory))))
            (fb (make-temp-file (expand-file-name "scor"
                                                  (or small-temporary-file-directory
                                                      temporary-file-directory)))))
        ;;  save current content as file B
        (when fb
          (setq tmp (diff-region-format-region-boundary (region-beginning) (region-end)))
          (write-region (car tmp) (cadr tmp) fb))

        (setq rlt-buf (get-buffer-create "*Diff-region-output*"))
        (when (and fa (file-exists-p fa) fb (file-exists-p fb))
          ;; save region A as file A
          (save-current-buffer
            (set-buffer (get-buffer-create "*Diff-regionA*"))
            (write-region (point-min) (point-max) fa))
          ;; diff NOW!
          (setq diff-output (shell-command-to-string (format "diff -Nabur %s %s" fa fb)))
          ;; show the diff output
          (if (string= diff-output "")
              ;; two regions are same
              (message "Two regions are SAME!")
            ;; show the diff
            (save-current-buffer
              (switch-to-buffer-other-window rlt-buf)
              (set-buffer rlt-buf)
              (erase-buffer)
              (insert diff-output)
              (diff-mode)
              (if (fboundp 'evil-local-set-key)
                           (evil-local-set-key 'normal "q" 'diff-region-exit))
              (local-set-key (kbd "C-c C-c") 'diff-region-exit)
              )))

        ;; clean the temporary files
        (if (and fa (file-exists-p fa))
            (delete-file fa))
        (if (and fb (file-exists-p fb))
            (delete-file fb)))
    (message "Please select region at first!")))

Use ivy-mode to search bash history

(defun counsel-yank-bash-history ()
  "Yank the bash history"
  (interactive)
  (let (hist-cmd collection val)
    (shell-command "history -r") ; reload history
    (setq collection
          (nreverse
           (split-string (with-temp-buffer (insert-file-contents (file-truename "~/.bash_history"))
                                           (buffer-string))
                         "\n"
                         t)))
    (when (and collection (> (length collection) 0)
               (setq val (if (= 1 (length collection)) (car collection)
                           (ivy-read (format "Bash history:") collection))))
        (kill-new val)
        (message "%s => kill-ring" val))))

How to use Gnus Group Topics efficiently

Group Topics is used to manage Gnus groups.

For example, you can,

  • Place groups (mail folders) from Gmail into "gmail" topic
  • Place groups (mails folders) from Outlook.com into "hotmail" topic
  • Make "gmail" and "hotmail" belong to the root topic "Gnus"

Enable it is just one line,

(add-hook 'gnus-group-mode-hook 'gnus-topic-mode)

Now comes the question how to delete/add/move the topics?

The official answer is to read its manual.

But there is a simpler solution. All you need to do is insert below code into ~/.emacs or ~/.gnus.el,

(eval-after-load 'gnus-topic
  '(progn
     (setq gnus-topic-topology '(("Gnus" visible)
                                 (("hotmail" visible nil nil))
                                 (("gmail" visible nil nil))))

     (setq gnus-topic-alist '(("hotmail" ; the key of topic
                               "nnimap+hotmail:Inbox"
                               "nnimap+hotmail:Drafts"
                               "nnimap+hotmail:Sent"
                               "nnimap+hotmail:Junk"
                               "nnimap+hotmail:Deleted")
                              ("gmail" ; the key of topic
                               "INBOX"
                               "[Gmail]/Sent Mail"
                               "[Gmail]/Trash"
                               "Drafts")
                              ("Gnus")))))

The management of topics is as easy as editing above code.

My setup always works no matter ~/.newsrc.eld is loaded or not.

BTW, "hotmail" and "gmail" are the keys you used when configuring IMAP accounts,

(setq gnus-select-method
             '(nnimap "gmail" ; key
                      (nnimap-address "imap.gmail.com")
                      (nnimap-server-port 993)
                      (nnimap-stream ssl)))
(add-to-list 'gnus-secondary-select-methods
             '(nnimap "hotmail" ; key
                      (nnimap-address "imap-mail.outlook.com")
                      (nnimap-server-port 993)
                      (nnimap-stream ssl)))

Git gutter tip

I use git-gutter.el everyday. It indicats "whether a line has been inserted, modified or deleted". You can jump to the inser/modified/deleted line easily.

But I usually need to know what line changed in latest commit.

So I designed `M-x git-gutter-reset-to-head-parent`,

(defun git-gutter-reset-to-head-parent()
  (interactive)
  (let (parent (filename (buffer-file-name)))
    (if (eq git-gutter:vcs-type 'svn)
        (setq parent "PREV")
      (setq parent (if filename (concat (shell-command-to-string (concat "git --no-pager log --oneline -n1 --pretty='format:%H' " filename)) "^") "HEAD^")))
    (git-gutter:set-start-revision parent)
    (message "git-gutter:set-start-revision HEAD^")))

(defun git-gutter-reset-to-default ()
  (interactive)
  (git-gutter:set-start-revision nil)
  (message "git-gutter reset"))

`M-x git-gutter-reset-to-default` compare you file under working directory with the latet version under VCS.

`M-x git-gutter:next-hunk` and `M-x git-gutter:previous-hunk` will jump to the deleted/modified/added line.

Use gcalcli for google calendar

I use cli `pip install –user gcalcli parsedatetime` to install gcalcli into HOME folder.

Usage is simple. `gcalcli calw` is enough.

For multiple accounts, `mkdir -p ~/.config/gcacli-work; gcalcli –configFolder ~/.config/gcacli-work calw`.

Use paste (Unix) to join two calendars in bash,

paste <(gcalcli --configFolder ~/.config/gcacli-work calw) <(gcalcli calw)

Edit crontab to remind me about the calendar events,

*/10 * * * * $HOME/.local/bin/gcalcli remind
*/10 * * * * $HOME/.local/bin/gcalcli --configFolder $HOME/.config/gcacli-work remind

Use Ivy-mode to tweak workgroups2

CREATED: <2015-12-22>

UPDATED: <2016-04-21 Thu>

Workgroups2 will load previous windows layout by default. That's handy for most developers.

But as a freelancer I am assigned a low spec computer. It takes too long to load the old windows layout.

So I use Ivy-mode to create a light weight command `my-wg-switch-workgroup`.

Here is code:

(setq wg-use-default-session-file nil)
;; don't open last workgroup automatically in `wg-open-session',
;; I only want to check available workgroups! Nothing more.
(setq wg-load-last-workgroup nil)
(setq wg-open-this-wg nil)

;(workgroups-mode 1) ; put this one at the bottom of .emacs
;; by default, the sessions are saved in "~/.emacs_workgroups"
(autoload 'wg-create-workgroup "workgroups2" nil t)

(defun my-wg-switch-workgroup ()
  (interactive)
  (let (group-names selected-group)
    (unless (featurep 'workgroups2)
      (require 'workgroups2))
    (setq group-names
          (mapcar (lambda (group)
                    ;; re-shape list for the ivy-read
                    (cons (wg-workgroup-name group) group))
                  (wg-session-workgroup-list (read (f-read-text (file-truename wg-session-file))))))
    (ivy-read "work groups" group-names
              :action (lambda (group)
                        (wg-find-session-file wg-default-session-file)
                        (wg-switch-to-workgroup group)))))

(eval-after-load 'workgroups2
  '(progn
     ;; make sure wg-create-workgroup always success
     (defadvice wg-create-workgroup (around wg-create-workgroup-hack activate)
       (unless (file-exists-p (wg-get-session-file))
         (wg-reset t)
         (wg-save-session t))

       (unless wg-current-session
         ;; code extracted from `wg-open-session'.
         ;; open session but do NOT load any workgroup.
         (let ((session (read (f-read-text (file-truename wg-session-file)))))
           (setf (wg-session-file-name session) wg-session-file)
           (wg-reset-internal (wg-unpickel-session-parameters session))))
       ad-do-it
       ;; save the session file in real time
       (wg-save-session t))

     (defadvice wg-reset (after wg-reset-hack activate)
       (wg-save-session t))

     ;; I'm fine to to override the original workgroup
     (defadvice wg-unique-workgroup-name-p (around wg-unique-workgroup-name-p-hack activate)
       (setq ad-return-value t))))