cabbr definitions disturb searching in Vim

Question

I like to define some abbreviations like:

cabbr csf cscope find

I thought cabbr would just be interpreted in the : command line. However, when I entered the search mode \, I found that \csf would still be expanded to \cscope find, which definitely was not what I want.
So how to deal with this situation? If I do want to search csf, what should I do? Or there is another kind of abbreviation other than cabbr intended to be valid just in the : command line? Thanks very much!

Answer 1

What you can do is use an expression abbreviation. This will allow you to use any Vim expression on the right-hand side, instead of just a static string. With getcmdtype() we can check if we're doing a normal Ex command or something else.

cabbr <expr> csf getcmdtype() == ':' ? 'cscope find' : 'csf'

See :help :map-<expr> for the documentation.

Answer 2

You could also define 2 custom commands :Cab and :Sab which would make the definition of such abbreviations easier.
:Cab would define an abbreviation which would only affect an Ex command, while :Sab would only modify a search.

The following code tries to define these commands:

command! -nargs=+ Cab call s:StrictAbbr(<q-args>, 1)
command! -nargs=+ Sab call s:StrictAbbr(<q-args>, 0)

function! s:StrictAbbr(args, cmd) abort
    let l:lhs = matchstr(a:args, '^\s*\zs\S*')
    let l:rhs = matchstr(a:args, '^\s*\S*\s\+\zs.*')
    if a:cmd
        execute printf("cnoreabbrev <expr> %s getcmdtype() ==# ':' ? '%s' : '%s'", l:lhs, l:rhs, l:lhs)
    else
        execute printf("cnoreabbrev <expr> %s getcmdtype() =~ '[/?]' ? '%s' : '%s'", l:lhs, l:rhs, l:lhs)
    endif
endfunction

Now to define the abbreviation mentioned in your post, you could write :

Cab csf cscope find

And to define the abbreviation which transforms fb in foo bar, but only in a search:

Sab fb foo bar

These abbreviations could be written anywhere in your vimrc, but only after the previous code, otherwise you'll have an error such as:

E492: Not an editor command: Sab fb foo bar

The code is heavily inspired from this post and from the accepted answer.