Reformat a Python file to have 4 space indentations

Question

I'm editing a Python file that uses two spaces for programmatic indents - I prefer 4 spaces. In my .vimrc I have the following settings related to indentation:

set tabstop=4                     "Indentation levels every four columns
set expandtab                     "Convert all tabs typed to spaces
set shiftwidth=4                  "Indent/outdent by four columns
set softtabstop=4

How do I get Vim to convert all the existing 2 space indents to be 4 space indents?

In other words:

if something:
  dothis()

becomes

if something:
    dothis()

When I tried gg=G

def check():
  for a in list:
    for  b in list2:
      check(a, b)
      while (len > MAX) :
        poll()

  while(len(thelist) > 0) :
    poll()  

  return results

became

def check():
    for a in list:
    for  b in list2:
    check(a, b)
    while (len > MAX) : 
        poll()

        while(len(thelist) > 0) :
            poll()

            return results

Answer 1

In order to double the number of spaces at the beginning of every line (and only at the beginning):

:%s/^\s*/&&/g

& in replacement pattern is the matched pattern.

Probably it will not have any side-effect for you.

Answer 2

Pressing gg=G is the command to re-indent everything in a file. If you have other elements that can be re-indented, vim will indent these as well, which doesn't always give the desired effects. You'll have to clean these up manually if they're ugly.

Alternately, you can use the > command to indent, with ranges to go through the file somewhat efficiently manually. 99>k , for example, would indent the 99 lines below the cursor by one level.

Answer 3

I've found the reindent script http://pypi.python.org/pypi/Reindent/0.1.0 works well for me. Not pure vim, but really easy!

After its installed you can use it in vim with

:%! reindent

(ie pipe the entire buffer through the reindent program) and it's done.

From the command line it can be used to reindent multiple files (eg all files in a directory, or even recursively down a directory tree).

Answer 4

try the following substitution command:

:%s/  /    /g

(To clarify: there are two spaces between the first and second '/' and four the second and third '/'.)

One helpful command when working with whitespace issues is also the set list command which will visually show all whitespace. Use set nolist to unset.

Answer 5

The best current way to reformat Python, fix many other issues, and also make it PEP8 compliant is to use autopep8 . See this related question . So after you've installed autopep8 (eg pip install autopep8 ) in vim you do:

:%! autopep8 -

There's also a vim-autopep8 plugin to make things even simpler.

Answer 6

The vim plugin vim-autoformat integrates the formatter autopep8 into vim automatically, if it is installed. You can format the whole file, or the visually selected part using a single keystroke.

More importantly, vim-autoformat takes the relevant settings of your .vimrc into account, eg if you have

set shiftwidth=4

in your .vimrc , it will pass this information on to autopep8.

Answer 7

Have you tried?

:retab

I'm not in front of a machine with Vim at the moment so I can't verify this.