Auto-complete word in Emacs mini-buffer when using Evil

When using Evil I often input %s/old-keyword/new-keyword/g in Minibuffer.

The problem is auto completions of new-keyword using hippie-expand always fail.

It turns out that the character "/" is treated as Word constituent in minibuffer.

The solution is to re-define "/" as Punctuation characters:

(defun minibuffer-inactive-mode-hook-setup ()
  ;; make `try-expand-dabbrev' from `hippie-expand' work in mini-buffer
  ;; @see `he-dabbrev-beg', so we need re-define syntax for '/'
  (set-syntax-table (let* ((table (make-syntax-table)))
                      (modify-syntax-entry ?/ "." table)
(add-hook 'minibuffer-inactive-mode-hook 'minibuffer-inactive-mode-hook-setup)

Indent JSX in Emacs

I find rjsx-mode annoying when it indents closed html tag with extra spaces.

It's based on js2-mode which is actually just calling Emacs v25 API js-jsx-indent-line.

So the solution is as simple as advice js-jsx-indent-line:

(defadvice js-jsx-indent-line (after js-jsx-indent-line-after-hack activate)
  "Workaround sgml-mode and follow airbnb component style."
  (let* ((cur-line (buffer-substring-no-properties
    (if (string-match "^\\( +\\)\/?> *$" cur-line)
      (let* ((empty-spaces (match-string 1 cur-line)))
        (replace-regexp empty-spaces
                        (make-string (- (length empty-spaces) sgml-basic-offset) 32)
                        (line-beginning-position) (line-end-position))))))

Find the buffer with Chinese name

We can find the buffer with Chinese name efficiently by using the first character of pinyin.

Here is the code (ivy and pinyinlib is required):

(defun ivy-switch-buffer-matcher-pinyin (regexp candidates)
  (unless (featurep 'pinyinlib) (require 'pinyinlib))
  (let* ((pys (split-string regexp "[ \t]+"))
         (regexp (format ".*%s.*"
                         (mapconcat 'pinyinlib-build-regexp-string pys ".*"))))
    (ivy--switch-buffer-matcher regexp candidates)))

(defun ivy-switch-buffer-by-pinyin ()
  "Switch to another buffer."
  (unless (featurep 'ivy) (require 'ivy))
  (let ((this-command 'ivy-switch-buffer))
    (ivy-read "Switch to buffer: " 'internal-complete-buffer
              :matcher #'ivy-switch-buffer-matcher-pinyin
              :preselect (buffer-name (other-buffer (current-buffer)))
              :action #'ivy--switch-buffer-action
              :keymap ivy-switch-buffer-map
              :caller 'ivy-switch-buffer)))

You can M-x ivy-switch-buffer-by-pinyin to switch buffer.

The algorithm of pinyinlib is simple. We build a big lookup table to convert the a plain English string into a regular expression containing Chinese characters.

You can apply the same algorithm to other non-English languages.