Question

when I open Python files my indentation changes. I have the following vimrc settings:

set number
colorscheme wombat256mod
set guifont=Consolas\ 11
set linespace=2
filetype on
filetype plugin on

au BufRead,BufNewFile *py,*pyw,*.c,*.h set tabstop=4
au BufRead,BufNewFile *.py,*pyw set shiftwidth=4
au BufRead,BufNewFile *.py,*.pyw set expandtab
fu Select_c_style()
    if search('^\t', 'n', 150)
    set shiftwidth=8
    set noexpandtab
    el 
    set shiftwidth=4
    set expandtab
    en
endf
au BufRead,BufNewFile *.c,*.h call Select_c_style()
au BufRead,BufNewFile Makefile* set noexpandtab
highlight BadWhitespace ctermbg=red guibg=red
au BufRead,BufNewFile *.py,*.pyw match BadWhitespace /^\t\+/
au BufRead,BufNewFile *.py,*.pyw,*.c,*.h match BadWhitespace /\s\+$/
au BufRead,BufNewFile *.py,*.pyw,*.c,*.h set textwidth=79
au BufRead,BufNewFile *.c,*.h set formatoptions-=c formatoptions-=o formatoptions-=r
au BufNewFile *.py,*.pyw,*.c,*.h set fileformat=unix
let python_highlight_all=1
syntax on
filetype indent on
set autoindent

Anybody see something that can cause it?

For example I open an *.html file the indentation is a tab. But once I opened any Python file and go back to the html file the indentation switches to python preferences.

Answer 1

The au lines with *.py in them are what are changing your settings. Notably,

au BufRead,BufNewFile *.py,*pyw set shiftwidth=4
au BufRead,BufNewFile *.py,*.pyw set expandtab

You need to “undo” these settings when opening HTML files. Just add a few more autocmds that work on *.html to set noexpandtab and set your shiftwidth back to 8.