Setting vim filetype with modeline not working as expected

Question

As per the accepted answer to this question, I'm attempting to use modelines in vim to force filetype detection in some files.

For example, at the top of a file named gitconfig (note there is no leading .), I have the following line:

# vim: set filetype=gitconfig : 

modeline is enabled on my system. However, when I open the file in vim, set filetype? returns conf, rather than the expected gitconfig.

Is it possible that other parts of my vim configuration (e.g. filetype.vim) are causing this strange behaviour?

Edited in response to comments:

set compatible? returns nocompatible

set modeline? returns modeline

verbose set filetype? returns:

filetype=conf
      Last set from /usr/share/vim/vim73/filetype.vim

I don't understand why the system wide filetype plugin would be overriding what I have set in the file itself.

One final note: this is the version of Vim 7.3 shipped with OSX.

The latest version of MacVim running on the same system using the same .vimrc behaves as expected, with set ft? returning filetype=gitconfig.

Answer 1

So, after some digging, it transpires that the system vimrc shipped with OSX sets the modelines (note the trailing 's') variable to 0. This variable controls the number of lines in a file which are checked for set commands. Setting modelines to a non-zero value in my .vimrc solved the problem.

Full output, for the curious: the output of vim --version prompted me to check the system vimrc:

% vim --version
VIM - Vi IMproved 7.3 (2010 Aug 15, compiled Jun 24 2011 20:00:09)
Compiled by [email protected]
Normal version without GUI.  Features included (+) or not (-):
...
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
      user exrc file: "$HOME/.exrc"
  fall-back for $VIM: "/usr/share/vim"
Compilation: gcc -c -I. -D_FORTIFY_SOURCE=0 -Iproto -DHAVE_CONFIG_H -arch i386 -arch x86_64 -g -Os -pipe
Linking: gcc -arch i386 -arch x86_64 -o vim -lncurses

Looking at the system vimrc:

% cat /usr/share/vim/vimrc 
" Configuration file for vim
set modelines=0         " CVE-2007-2438
...

Led me to the modelines variable. It appears that MacVim does not source this system file (perhaps looking for a system GVIMRC instead? :help startup isn't clear).

VIM - Vi IMproved 7.3 (2010 Aug 15, compiled Jul 27 2011 19:46:24)
MacOS X (unix) version
Included patches: 1-260
Compiled by XXXXX
Huge version with MacVim GUI.  Features included (+) or not (-):
...
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
      user exrc file: "$HOME/.exrc"
  system gvimrc file: "$VIM/gvimrc"
    user gvimrc file: "$HOME/.gvimrc"
    system menu file: "$VIMRUNTIME/menu.vim"
  fall-back for $VIM: "/Applications/MacVim.app/Contents/Resources/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_MACVIM -Wall -Wno-unknown-pragmas -p
ipe  -DMACOS_X_UNIX -no-cpp-precomp  -g -O2 -D_FORTIFY_SOURCE=1
Linking: gcc   -L.         -Wl,-syslibroot,/Developer/SDKs/MacOSX10.6.sdk -L/usr/local/lib -o V
im -framework Cocoa -framework Carbon      -lncurses  -liconv -framework Cocoa    -fstack-prote
ctor -L/usr/local/lib  -L/System/Library/Perl/5.10/darwin-thread-multi-2level/CORE -lperl -lm -
lutil -lc -framework Python   -framework Ruby

Answer 2

For this to work on my macOS system I had to define a couple of settings in ~/.vimrc:

modeline
modelines=2

Where 'modeline' enables the use of in-file settings, and 'modelines=#' sets the number of lines that vim/vi will check for set commands.

Once those parameters were set I was able to use syntax like the line below in my files to override set parameters.

# vim: ts=4 sw=4 ai