yank-indent

Emacs minor-mode that ensures pasted (yanked) text has the correct indentation level.

Do you often find yourself fixing the indentation of a code snippet right after pasting it somewhere? Never again! yank-indent is the answer.

Features

A fire-and-forget style global mode that does the right thing most of time. Can be customized if you find it enables yank-indent-mode when it shouldn't.
Configurable size threshold to prevent triggering indentation on very large regions which may cause performance issues in with some major-modes.

Installation

use-package + straight.el

(use-package yank-indent
  :straight (:host github :repo "jimeh/yank-indent")
  :config (global-yank-indent-mode t))

Manual

Place yank-indent.el somewhere in your load-path and require it. For example ~/.emacs.d/vendor:

(add-to-list 'load-path "~/.emacs.d/vendor")
(require 'yank-indent)
(global-yank-indent-mode t)

Usage

`global-yank-indent-mode`

With global-yank-indent-mode enabled, you will find that yank-indent-mode is automatically enabled in relevant buffers. The defaults will specifically exclude common languages which are indentation sensitive like Python, YAML, Makefile, etc.

For fine-grained control over which major-modes it is enabled in or not, see customization options with M-x customize-group RET yank-indent.

`yank-indent-mode`

If you prefer not to use the global mode, you can add yank-indent-mode as a hook to relevant major-modes, or even manually toggle it on and off with M-x yank-indent-mode.

To skip the indent operation for a single yank command, use a prefix command, so C-u C-y instead of just C-y.

Keep in mind that the include/exclude major-mode customizations only affect the global mode and which buffers it enables yank-indent-mode in. If you explicitly enable yank-indent-mode in a buffer, it will operate like normal regardless of what major-mode the buffer is using.

Under the Hood

yank-indent registers an advice for after yank and yank-pop commands. The advice function verifies that yank-indent-mode mode is enabled in the current buffer, prefix argument was not given, and the yanked/pasted text was within the yank-indent-threshold in size. If all true, it will trigger indentation, otherwise it does nothing.