Vim script to compile TeX source and launch PDF only if no errors

Question

I am switching to using Vim for for my LaTeX editing environment. I would like to be able to tex the source file from within Vim, and launch an external viewing if the compile was successful.

I know about the Vim-Latex suite, but, if possible, would prefer to avoid using it: it is pretty heavy-weight, hijacks a lot of my keys, and clutters up my vimruntime with a lot of files.

Here is what I have now:

if exists('b:tex_build_mapped')
    finish
endif
" use maparg or mapcheck to see if key is free
command! -buffer -nargs=* BuildTex call BuildTex(0, <f-args>)
command! -buffer -nargs=* BuildAndViewTex call BuildTex(1, <f-args>)
noremap <buffer> <silent> <F9> <Esc>:call BuildTex(0)<CR>
noremap <buffer> <silent> <S-F9> <Esc>:call BuildTex(1)<CR>
let b:tex_build_mapped = 1

if exists('g:tex_build_loaded')
    finish
endif
let g:tex_build_loaded = 1

function! BuildTex(view_results, ...)
    write
    if filereadable("Makefile")
        " If Makefile is available in current working directory, run 'make' with arguments
        echo "(using Makefile)"
        let l:cmd = "!make ".join(a:000, ' ')
        echo l:cmd
        execute l:cmd
        if a:view_results && v:shell_error == 0
            call ViewTexResults()
        endif
    else
        let b:tex_flavor = 'pdflatex'
        compiler tex
        make %
        if a:view_results && v:shell_error == 0
            call ViewTexResults()
        endif
    endif
endfunction

function! ViewTexResults(...)
    if a:0 == 0
        let l:target = expand("%:p:r") . ".pdf"
    else
        let l:target = a:1
    endif
    if has('mac')
        execute "! open -a Preview ".l:target
    endif
endfunction

The problem is that v:shell_error is not set, even if there are compile errors. Any suggestions or insight on how to detect whether a compile was successful or not would be greatly appreciated! Thanks!

---

Between the answers given here, plus some study of other approaches, I think that this has been satisfactorily solved. I am posting the solution here in case anyone else is interested.

Basically, the best solution appears to be to use Rubber, a wrapper around LaTeX, that generally "just works", and provides very clean output/errors. The solution I present below preferentially uses Rubber if it is found on the system and no Makefile is found in the current directory. If a Makefile is found, it uses that instead. If there is no Makefile and Rubber is not installed, it uses pdflatex. In all cases, if the source fails to compile, the (filtered and parsed) errors are sent to the QuickFix buffer and the QuickFix window is automatically opened. If it compiles successfully, a short message is written, and if the user requested it, the PDF will be opened for viewing.

In my own installation, I have lifted the (excellent) "SetLatexEfm()" function from Vim-Latex to parse and filter the tex build output. If this function is not found, however, the function below defaults to setting an error message format that works fine enough for the errors to be identified and highlighted in the QuickFix window, albeit with lots of crud.

    function! BuildTex(view_results, ...)

        " record position
        let save_cursor = getpos(".")

        " save work
        silent write

        " From: http://stackoverflow.com/questions/2679475/vim-script-to-compile-tex-source-and-launch-pdf-only-if-no-errors
        " If your shell is bash, you can use the ${PIPESTATUS} array variable to get
        " the correct exit code (borrowed from this answer to another question).
        silent setlocal shell=bash
        silent setlocal shellpipe=2>&1\ \|\ tee\ %s;exit\ \${PIPESTATUS[0]}

        let success = 1
        if filereadable("Makefile")
            " If Makefile is available in current working directory, run 'make' with arguments
            echon "compiling using Makefile ..."
            let l:makecmd = "make\\ ".join(a:000, '\\ ')
            silent execute "setlocal makeprg=" . l:makecmd
            try
                " This function is defined in the Vim-Latex package, 
                " and provides excellent parsing and filtering of the error messages
                " when running latex outside of the Rubber wrapper.
                call s:SetLatexEfm()
            catch /E117/
                set errorformat=%E!\ LaTeX\ %trror:\ %m,
                    \%E!\ %m,
                    \%+WLaTeX\ %.%#Warning:\ %.%#line\ %l%.%#,
                    \%+W%.%#\ at\ lines\ %l--%*\\d,
                    \%WLaTeX\ %.%#Warning:\ %m,
                    \%Cl.%l\ %m,
                    \%+C\ \ %m.,
                    \%+C%.%#-%.%#,
                    \%+C%.%#[]%.%#,
                    \%+C[]%.%#,
                    \%+C%.%#%[{}\\]%.%#,
                    \%+C<%.%#>%.%#,
                    \%C\ \ %m,
                    \%-GSee\ the\ LaTeX%m,
                    \%-GType\ \ H\ <return>%m,
                    \%-G\ ...%.%#,
                    \%-G%.%#\ (C)\ %.%#,
                    \%-G(see\ the\ transcript%.%#),
                    \%-G\\s%#,
                    \%+O(%f)%r,
                    \%+P(%f%r,
                    \%+P\ %\\=(%f%r,
                    \%+P%*[^()](%f%r,
                    \%+P[%\\d%[^()]%#(%f%r,
                    \%+Q)%r,
                    \%+Q%*[^()])%r,
                    \%+Q[%\\d%*[^()])%r
            endtry
            silent make
        else
            let l:special_tex_compiler = "rubber"
            if executable(l:special_tex_compiler)
                echon "compiling with Rubber ..."
                silent execute "setlocal makeprg=" . l:special_tex_compiler . "\\ -dfs\\ %"
                setlocal errorformat=%f:%l:\ %m
                silent make %
            else
                echon "compiling ..."
                let b:tex_flavor = 'pdflatex'
                compiler tex
                silent make %
            endif
        endif

        " set/report compile status
        if v:shell_error
            let l:success = 0
            " let l:wheight = winheight(bufnr("%")) / 2
            " execute "copen ".l:wheight
            copen
        else
            let l:success = 1
            cclose
            redraw
            echon "successfully compiled"
        endif

        " view results if successful compile
        if l:success && a:view_results
            call ViewTexResults()
        endif

        " restore position
        call setpos('.', save_cursor)

    endfunction

    function! ViewTexResults(...)
        if a:0 == 0
            let l:target = expand("%:p:r") . ".pdf"
        else
            let l:target = a:1
        endif
        if has('mac')
            silent execute "! open -a Preview ".l:target
            " obviously, you will need to write specific commands for other systems
            " left as an exercise for the reader ...
        endif
    endfunction

    command! -buffer -nargs=* BuildTex call BuildTex(0, <f-args>)
    command! -buffer -nargs=* BuildAndViewTex call BuildTex(1, <f-args>)
    noremap <buffer> <silent> <F9> <Esc>:call BuildTex(0)<CR>
    noremap <buffer> <silent> <S-F9> <Esc>:call BuildTex(1)<CR>

---

Update: I have packaged and published this as a Vim file-type plugin script, available at: http://www.vim.org/scripts/script.php?script_id=3230.

Answer 1

Assuming you're falling into the else-theres-no-makefile section, the issue may be with the shellpipe variable.

On my system (Ubuntu), shellpipe=2>&1| tee and the built-in make call doesn't set v:shell_error if it fails.

The return status of | tee might be what v:shell_error is getting set to.

If your shell is bash, you can use the ${PIPESTATUS} array variable to get the correct exit code (borrowed from this answer to another question).

:set shellpipe=2>&1\ \|\ tee\ %s;exit\ \${PIPESTATUS[0]}

Otherwise, you can try:

:set shellpipe=\>
:make %

This sets v:shell_error when it fails but I'm not sure if that will mess with the go-to-error-line-number functionality, if there is any.

To see what the variable is set to:

:set shellpipe?

Answer 2

I know it's not related to vim, but I think that latexmk does the job.

It's a script (written in perl) which compile the latex file and update the pdf. The most useful future is the auto-update one. As soon as you save your file, 'latexmk' compile it, and if your pdf viewer supports it, the view is updated.

latexmk -pdf -pvc