Question

I want to change the indentation in all my existing(!) Python files from 2-space to 4-space shift width. Any suggestions how to do this in Vim?

Answer 1

Note that :set ts=4 sw=4 alone will suffice if you use hard tabs (i.e. noexpandtab), but I assume that’s not the case. It’s still possible to utilize this functionality, though, by temporarily setting noet:

:set noet | retab! | set ts=4 sw=4 et | retab

This converts existing spaces to tabs, changes the number of spaces per tab, and reverts to spaces. Note that retab may affect sequences of spaces elsewhere in the file.

It’s also possible to manually substitute each pair of leading spaces with twice as many:

:%s/^\(\(\s\{2}\)\+\)/\1\1/g

This approach isn’t as generic, though.