Add a mechanism for handling checkers disabled for security.

plugin/syntastic.vim

@@ -19,7 +19,7 @@ if has('reltime')
     lockvar! g:_SYNTASTIC_START
 endif
 
-let g:_SYNTASTIC_VERSION = '3.6.0-114'
+let g:_SYNTASTIC_VERSION = '3.6.0-115'
 lockvar g:_SYNTASTIC_VERSION
 
 " Sanity checks {{{1

plugin/syntastic/checker.vim

@@ -25,6 +25,10 @@ function! g:SyntasticChecker.New(args) abort " {{{2
         let prefix = 'SyntaxCheckers_' . newObj._filetype . '_' . newObj._name . '_'
     endif
 
+    if has_key(a:args, 'enable')
+        let newObj._enable = a:args['enable']
+    endif
+
     let newObj._locListFunc = function(prefix . 'GetLocList')
 
     if exists('*' . prefix . 'IsAvailable')
@@ -78,6 +82,21 @@ endfunction " }}}2
 
 function! g:SyntasticChecker.getLocListRaw() abort " {{{2
     let name = self._filetype . '/' . self._name
+
+    if has_key(self, '_enable')
+        let status = syntastic#util#var(self._enable, -1)
+        if status < 0
+            call syntastic#log#error('checker ' . name . ': checks disabled for security reasons; ' .
+                \ 'set g:syntastic_' . self._enable . ' to 1 to override')
+        endif
+        if status <= 0
+            call syntastic#log#debug(g:_SYNTASTIC_DEBUG_TRACE, 'getLocList: checker ' . name . ' enabled but not forced')
+            return []
+        else
+            call syntastic#log#debug(g:_SYNTASTIC_DEBUG_TRACE, 'getLocList: checker ' . name . ' forced')
+        endif
+    endif
+
     try
         let list = self._locListFunc()
         if self._exec !=# ''
@@ -152,6 +171,10 @@ function! g:SyntasticChecker.isAvailable() abort " {{{2
     return self._available
 endfunction " }}}2
 
+function! g:SyntasticChecker.isDisabled() abort " {{{2
+    return has_key(self, '_enable') && syntastic#util#var(self._enable, -1) <= 0
+endfunction " }}}2
+
 function! g:SyntasticChecker.wantSort() abort " {{{2
     return syntastic#util#var(self._filetype . '_' . self._name . '_sort', 0)
 endfunction " }}}2

plugin/syntastic/registry.vim

@@ -181,12 +181,18 @@ function! g:SyntasticRegistry.getCheckers(ftalias, hints_list) abort " {{{2
         \ self._filterCheckersByName(checkers_map, names) : [checkers_map[keys(checkers_map)[0]]]
 endfunction " }}}2
 
-" Same as getCheckers(), but keep only the checkers available.  This runs the
+" Same as getCheckers(), but keep only the available checkers.  This runs the
 " corresponding IsAvailable() functions for all checkers.
 function! g:SyntasticRegistry.getCheckersAvailable(ftalias, hints_list) abort " {{{2
     return filter(self.getCheckers(a:ftalias, a:hints_list), 'v:val.isAvailable()')
 endfunction " }}}2
 
+" Same as getCheckers(), but keep only the checkers tyhat are available and
+" disabled.  This runs the corresponding IsAvailable() functions for all checkers.
+function! g:SyntasticRegistry.getCheckersDisabled(ftalias, hints_list) abort " {{{2
+    return filter(self.getCheckers(a:ftalias, a:hints_list), 'v:val.isDisabled() && v:val.isAvailable()')
+endfunction " }}}2
+
 function! g:SyntasticRegistry.getKnownFiletypes() abort " {{{2
     let types = keys(s:_DEFAULT_CHECKERS)
 
@@ -214,15 +220,18 @@ function! g:SyntasticRegistry.echoInfoFor(ftalias_list) abort " {{{2
     if len(ft_list) != 1
         let available = []
         let active = []
+        let disabled = []
 
         for ft in ft_list
             call extend(available, map( self.getNamesOfAvailableCheckers(ft), 'ft . "/" . v:val' ))
             call extend(active, map( self.getCheckersAvailable(ft, []), 'ft . "/" . v:val.getName()' ))
+            call extend(disabled, map( self.getCheckersDisabled(ft, []), 'ft . "/" . v:val.getName()' ))
         endfor
     else
         let ft = ft_list[0]
         let available = self.getNamesOfAvailableCheckers(ft)
         let active = map(self.getCheckersAvailable(ft, []), 'v:val.getName()')
+        let disabled = map(self.getCheckersDisabled(ft, []), 'v:val.getName()')
     endif
 
     let cnt = len(available)
@@ -235,6 +244,13 @@ function! g:SyntasticRegistry.echoInfoFor(ftalias_list) abort " {{{2
     let cklist = cnt ? join(active) : '-'
     echomsg 'Currently enabled checker' . plural . ': ' . cklist
 
+    let cnt = len(disabled)
+    let plural = cnt != 1 ? 's' : ''
+    if len(disabled)
+        let cklist = join(sort(disabled))
+        echomsg 'Checker' . plural . ' disabled for security reasons: ' . cklist
+    endif
+
     " Eclim feels entitled to mess with syntastic's variables {{{3
     if exists(':EclimValidate') && get(g:, 'EclimFileTypeValidate', 1)
         let disabled = filter(copy(ft_list), 's:_disabled_by_eclim(v:val)')

syntax_checkers/elixir/elixir.vim

@@ -27,12 +27,6 @@ function! SyntaxCheckers_elixir_elixir_IsAvailable() dict
 endfunction
 
 function! SyntaxCheckers_elixir_elixir_GetLocList() dict
-    if !syntastic#util#var('enable_elixir_checker', 0)
-        call syntastic#log#error('checker elixir/elixir: checks disabled for security reasons; ' .
-            \ 'set g:syntastic_enable_elixir_checker to 1 to override')
-        return []
-    endif
-
     let make_options = {}
     let compile_command = 'elixir'
     let mix_file = syntastic#util#findFileInParent('mix.exs', expand('%:p:h', 1))
@@ -53,7 +47,8 @@ endfunction
 
 call g:SyntasticRegistry.CreateAndRegisterChecker({
     \ 'filetype': 'elixir',
-    \ 'name': 'elixir'})
+    \ 'name': 'elixir',
+    \ 'enable': 'enable_elixir_checker'})
 
 let &cpo = s:save_cpo
 unlet s:save_cpo

syntax_checkers/perl/perl.vim

@@ -51,12 +51,6 @@ function! SyntaxCheckers_perl_perl_IsAvailable() dict
 endfunction
 
 function! SyntaxCheckers_perl_perl_GetLocList() dict
-    if !syntastic#util#var('enable_perl_checker', 0)
-        call syntastic#log#error('checker perl/perl: checks disabled for security reasons; ' .
-            \ 'set g:syntastic_enable_perl_checker to 1 to override')
-        return []
-    endif
-
     if type(g:syntastic_perl_lib_path) == type('')
         call syntastic#log#oneTimeWarn('variable g:syntastic_perl_lib_path should be a list')
         let includes = split(g:syntastic_perl_lib_path, ',')
@@ -91,7 +85,8 @@ endfunction
 
 call g:SyntasticRegistry.CreateAndRegisterChecker({
     \ 'filetype': 'perl',
-    \ 'name': 'perl'})
+    \ 'name': 'perl',
+    \ 'enable': 'enable_perl_checker'})
 
 let &cpo = s:save_cpo
 unlet s:save_cpo

syntax_checkers/r/svtools.vim

@@ -46,11 +46,6 @@ function! SyntaxCheckers_r_svtools_IsAvailable() dict
 endfunction
 
 function! SyntaxCheckers_r_svtools_GetLocList() dict
-    if !syntastic#util#var('enable_r_svtools_checker', 0)
-        call syntastic#log#error('checker r/svtools: checks disabled for security reasons; set g:syntastic_enable_r_svtools_checker to 1 to override')
-        return []
-    endif
-
     let setwd = syntastic#util#isRunningWindows() ? 'setwd("' . escape(getcwd(), '"\') . '"); ' : ''
     let makeprg = self.getExecEscaped() . ' --slave --restore --no-save' .
         \ ' -e ' . syntastic#util#shescape(setwd . 'library(svTools); ' .
@@ -70,7 +65,8 @@ endfunction
 call g:SyntasticRegistry.CreateAndRegisterChecker({
     \ 'filetype': 'r',
     \ 'name': 'svtools',
-    \ 'exec': 'R' })
+    \ 'exec': 'R',
+    \ 'enable': 'enable_r_svtools_checker'})
 
 let &cpo = s:save_cpo
 unlet s:save_cpo