Add check for required executables

autoload/latex/complete.vim

@@ -1,11 +1,31 @@
 " {{{1 latex#complete#init
 function! latex#complete#init(initialized)
+  "
+  " Check if bibtex is available
+  "
+  if !executable('bibtex')
+    echom "Warning: bibtex completion not available"
+    echom "         Missing executable: bibtex"
+    let s:bibtex = 0
+  endif
+
+  "
+  " Check if kpsewhich is required and available
+  "
+  if g:latex_complete_recursive_bib && !executable('kpsewhich')
+    echom "Warning: bibtex completion not available"
+    echom "         Missing executable: kpsewhich"
+    echom "         You could try to turn off recursive bib functionality"
+    let s:bibtex = 0
+  endif
+
   if g:latex_complete_enabled
     setlocal omnifunc=latex#complete#omnifunc
   endif
 endfunction
 
 " {{{1 latex#complete#omnifunc
+let s:bibtex = 1
 let s:completion_type = ''
 function! latex#complete#omnifunc(findstart, base)
   if a:findstart
@@ -38,7 +58,7 @@ function! latex#complete#omnifunc(findstart, base)
     "
     if s:completion_type == 'ref'
       return latex#complete#labels(a:base)
-    elseif s:completion_type == 'bib'
+    elseif s:completion_type == 'bib' && s:bibtex
       return latex#complete#bibtex(a:base)
     endif
   endif
@@ -319,6 +339,7 @@ function! s:labels_extract_inputs(file)
   endfor
   return matches
 endfunction
+
 " }}}1
 
 " {{{1 s:next_chars_match

autoload/latex/latexmk.vim

@@ -2,6 +2,11 @@
 function! latex#latexmk#init(initialized)
   if !g:latex_latexmk_enabled | return | endif
 
+  "
+  " Check if system is incompatible with latexmk
+  "
+  if s:system_incompatible() | return | endif
+
   "
   " Initialize pid for current tex file
   "
@@ -187,6 +192,14 @@ function! latex#latexmk#stop_all()
 endfunction
 " }}}1
 
+" {{{1 s:execute
+function! s:execute(cmd)
+  silent execute a:cmd
+  if !has('gui_running')
+    redraw!
+  endif
+endfunction
+
 " {{{1 s:stop_buffer
 function! s:stop_buffer()
   "
@@ -219,13 +232,27 @@ function! s:stop_buffer()
   endif
 endfunction
 
-" {{{1 s:execute
-function! s:execute(cmd)
-  silent execute a:cmd
-  if !has('gui_running')
-    redraw!
+" {{{1 s:system_incompatible()
+function! s:system_incompatible()
+  "
+  " Windows will not be supported
+  "
+  if has('win32')
+    return 1
   endif
+
+  "
+  " Check if latexmk or pgrep is missing
+  "
+  for cmd in [ 'latexmk', 'pgrep' ]
+    if !executable(cmd)
+      echom "Warning: Could not initialize latex#latexmk"
+      echom "         Missing executable: " . cmd
+      return 1
+    endif
+  endfor
 endfunction
+
 " }}}1
 
 " vim:fdm=marker:ff=unix

doc/latex.txt

@@ -49,6 +49,18 @@ that is easy to customize and evolve.  Most of the functionality provided is
 turned on by default, but the user may turn off features that are not desired.
 The plugin will hereafter be referred to as |vim-latex|.
 
+                                                      *vim-latex-requirements*
+Some of the functionalities of |vim-latex| has certain requirements:
+
+  |vim-latex-latexmk|
+    Requires that the user has installed both `latexmk` and `pgrep`.  If these
+    are not available, then the functionalities provided by
+    |vim-latex-latexmk| will not be available.
+
+  |vim-latex-completion|
+    The function |latex#complete#bibtex| requires `bibtex` and `kpsewhich` to
+    parse bib files for bibliography completion.
+
 ==============================================================================
 MAIN INTERFACE                                                *vim-latex-main*