How to maintain tabs when pasting in Vim

Question

I use the tab key to indent my python code in Vim, but whenever I copy and paste a block Vim replaces every tab with 4 spaces, which raises an IndentationError

I tried setting :set paste as suggested in related questions but it makes no difference

Other sites suggest pasting 'tabless' code and using the visual editor to re-indent, but this is asking for trouble when it comes to large blocks

Are there any settings I can apply to vim to maintain tabs on copy/paste?

Thanks for any help with this :)

edit:

I am copying and pasting within vim using the standard gnome-terminal techniques (ctrl+shift+c / mouse etc.)

my .vimrc is:

syntax on
set ts=4
if has("terminfo")
let &t_Co=8
let &t_Sf="\e[3%p1%dm"
let &t_Sb="\e[4%p1%dm"
else
let &t_Co=8
let &t_Sf="\e[3%dm"
let &t_Sb="\e[4%dm"
endif

I looked up that ts -> Sets tab stops to n for text input, but don't know what value would maintain a tab character

Answer 1

See :h tabstop for all the options and how they interact with each other.

These are good settings if you prefer tabs:

set tabstop=4
set shiftwidth=4
set noexpandtab

With these settings, you hit <Tab> and you get <Tab>.

These are good settings if you prefer spaces:

set tabstop=4
set shiftwidth=4
set expandtab

With these settings, you hit <Tab> and you get <Space><Space><Space><Space>.

Whatever you choose, you should not use your terminal key bindings for copying/pasting. Inside Vim, you should "yank" with y and "put" with p or P; optionally using a specific register like "ay/"ap to yank/put to/from the content of @a or "+y/"+p to yank/paste to/from the system clipboard (if your Vim is built with clipboard support).

As a side note, you should use the long form names of your settings as they are more readable than their short counterpart. Your future self will thank you.

Answer 2

I was middle-click-pasting into a terminal vim instance. I have this in my vimrc:

set tabstop=2           " (ts)
set softtabstop=2       " (sts) Turned off with 0
set shiftwidth=2        " (sw)  Used for autoindent, and << and >>
set expandtab           " (et)  Expand tabs to spaces

I ran

:set paste
:set noexpandtab

and vim preserved the tabs that were in the source text. Without overriding my expandtab setting, vim was auto-expanding the tabs in the source text.