Cleanup.

plugin/syntastic.vim

@@ -165,7 +165,7 @@ augroup syntastic
 
     autocmd BufWinEnter * call s:BufWinEnterHook()
 
-    " TODO: the next autocmd should be "autocmd BufWinLeave * if empty(&buftype) | lclose | endif"
+    " TODO: the next autocmd should be "autocmd BufWinLeave * if &buftype == '' | lclose | endif"
     " but in recent versions of Vim lclose can no longer be called from BufWinLeave
     autocmd BufEnter * call s:BufEnterHook()
 augroup END
@@ -196,7 +196,7 @@ function! s:BufWinEnterHook()
     call syntastic#log#debug(g:SyntasticDebugAutocommands,
         \ 'autocmd: BufWinEnter, buffer ' . bufnr("") . ' = ' . string(bufname(str2nr(bufnr("")))) .
         \ ', &buftype = ' . string(&buftype))
-    if empty(&buftype)
+    if &buftype == ''
         let loclist = g:SyntasticLoclist.current()
         call s:notifiers.refresh(loclist)
     endif
@@ -386,7 +386,7 @@ endfunction
 function! s:SkipFile()
     let force_skip = exists('b:syntastic_skip_checks') ? b:syntastic_skip_checks : 0
     let fname = expand('%')
-    return force_skip || !empty(&buftype) || !filereadable(fname) || getwinvar(0, '&diff') || s:IgnoreFile(fname)
+    return force_skip || (&buftype != '') || !filereadable(fname) || getwinvar(0, '&diff') || s:IgnoreFile(fname)
 endfunction
 
 function! s:uname()

plugin/syntastic/checker.vim

@@ -31,8 +31,6 @@ function! g:SyntasticChecker.New(args)
 
     if exists('*' . prefix . 'GetHighlightRegex')
         let newObj._highlightRegexFunc = function(prefix . 'GetHighlightRegex')
-    else
-        let newObj._highlightRegexFunc = ''
     endif
 
     return newObj
@@ -73,10 +71,6 @@ function! g:SyntasticChecker.getLocList()
     return g:SyntasticLoclist.New(self.getLocListRaw())
 endfunction
 
-function! g:SyntasticChecker.getHighlightRegexFor(error)
-    return empty(self._highlightRegexFunc) ? [] : self._highlightRegexFunc(a:error)
-endfunction
-
 function! g:SyntasticChecker.makeprgBuild(opts)
     let setting = 'g:syntastic_' . self._filetype . '_' . self._name . '_'
 
@@ -86,7 +80,7 @@ function! g:SyntasticChecker.makeprgBuild(opts)
     call extend(parts, self._getOpt(a:opts, setting, 'post_args', ''))
     call extend(parts, self._getOpt(a:opts, setting, 'tail', ''))
 
-    return join(filter(parts, 'strlen(v:val)'))
+    return join(filter(parts, 'v:val != ""'))
 endfunction
 
 function! g:SyntasticChecker.isAvailable()
@@ -104,7 +98,7 @@ function! g:SyntasticChecker._quietMessages(errors)
 endfunction
 
 function! g:SyntasticChecker._populateHighlightRegexes(errors)
-    if !empty(self._highlightRegexFunc)
+    if has_key(self, '_highlightRegexFunc')
         for e in a:errors
             if e['valid']
                 let term = self._highlightRegexFunc(e)

plugin/syntastic/loclist.vim

@@ -13,7 +13,7 @@ function! g:SyntasticLoclist.New(rawLoclist)
     let llist = filter(copy(a:rawLoclist), 'v:val["valid"] == 1')
 
     for e in llist
-        if empty(e['type'])
+        if get(e, 'type', '') == ''
             let e['type'] = 'E'
         endif
     endfor

syntax_checkers/actionscript/mxmlc.vim

@@ -41,12 +41,12 @@ function! SyntaxCheckers_actionscript_mxmlc_GetHighlightRegex(item)
 
     endif
 
-    return strlen(term) ? '\V\<' . term . '\>' : ''
+    return term != '' ? '\V\<' . term . '\>' : ''
 endfunction
 
 function! SyntaxCheckers_actionscript_mxmlc_GetLocList() dict
     let makeprg = self.makeprgBuild({
-        \ 'args_before': (strlen(g:syntastic_actionscript_mxmlc_conf) ?
+        \ 'args_before': (g:syntastic_actionscript_mxmlc_conf != '' ?
         \   ' -load-config+=' . g:syntastic_actionscript_mxmlc_conf : ''),
         \ 'args_after': '-output=' . syntastic#util#DevNull() })
 

syntax_checkers/haxe/haxe.vim

@@ -28,7 +28,7 @@ function! SyntaxCheckers_haxe_haxe_GetLocList() dict
     endif
     let hxml = fnamemodify(hxml, ':p')
 
-    if !empty(hxml)
+    if hxml != ''
         let makeprg = self.makeprgBuild({
             \ 'fname': syntastic#util#shescape(fnameescape(fnamemodify(hxml, ':t'))) })
 

syntax_checkers/html/jshint.vim

@@ -34,7 +34,7 @@ endfunction
 function! SyntaxCheckers_html_jshint_GetLocList() dict
     let makeprg = self.makeprgBuild({
         \ 'exe': expand(g:syntastic_jshint_exec),
-        \ 'args': (!empty(g:syntastic_html_jshint_conf) ? ' --config ' . g:syntastic_html_jshint_conf : ''),
+        \ 'args': (g:syntastic_html_jshint_conf != '' ? '--config ' . g:syntastic_html_jshint_conf : ''),
         \ 'args_after': '--verbose --extract always' })
 
     let errorformat = '%A%f: line %l\, col %v\, %m \(%t%*\d\)'

syntax_checkers/html/validator.vim

@@ -66,8 +66,8 @@ endfunction
 function! SyntaxCheckers_html_validator_GetLocList() dict
     let fname = syntastic#util#shexpand('%')
     let makeprg = self.getExec() . ' -s --compressed -F out=gnu -F asciiquotes=yes' .
-        \ (!empty(g:syntastic_html_validator_parser) ? ' -F parser=' . g:syntastic_html_validator_parser : '') .
+        \ (g:syntastic_html_validator_parser != '' ? ' -F parser=' . g:syntastic_html_validator_parser : '') .
-        \ (!empty(g:syntastic_html_validator_nsfilter) ? ' -F nsfilter=' . g:syntastic_html_validator_nsfilter : '') .
+        \ (g:syntastic_html_validator_nsfilter != '' ? ' -F nsfilter=' . g:syntastic_html_validator_nsfilter : '') .
         \ ' -F doc=@' . fname . '\;type=text/html\;filename=' . fname . ' ' . g:syntastic_html_validator_api
 
     let errorformat =

syntax_checkers/javascript/eslint.vim

@@ -23,7 +23,7 @@ set cpo&vim
 
 function! SyntaxCheckers_javascript_eslint_GetLocList() dict
     let makeprg = self.makeprgBuild({
-        \ 'args': strlen(g:syntastic_javascript_eslint_conf) ? ' --config ' . g:syntastic_javascript_eslint_conf : '' })
+        \ 'args': (g:syntastic_javascript_eslint_conf != '' ? '--config ' . g:syntastic_javascript_eslint_conf : '') })
 
     let errorformat =
         \ '%E%f: line %l\, col %c\, Error - %m'

syntax_checkers/javascript/jshint.vim

@@ -37,7 +37,7 @@ function! SyntaxCheckers_javascript_jshint_GetLocList() dict
 
     let makeprg = self.makeprgBuild({
         \ 'exe': expand(g:syntastic_jshint_exec),
-        \ 'args': (strlen(g:syntastic_javascript_jshint_conf) ? '--config ' . g:syntastic_javascript_jshint_conf : ''),
+        \ 'args': (g:syntastic_javascript_jshint_conf != '' ? '--config ' . g:syntastic_javascript_jshint_conf : ''),
         \ 'args_after': (s:jshint_new ? '--verbose ' : '') })
 
     let errorformat = s:jshint_new ?

syntax_checkers/javascript/jsl.vim

@@ -23,7 +23,7 @@ set cpo&vim
 
 function! SyntaxCheckers_javascript_jsl_GetLocList() dict
     let makeprg = self.makeprgBuild({
-        \ 'args': (strlen(g:syntastic_javascript_jsl_conf) ? '-conf ' . g:syntastic_javascript_jsl_conf : ''),
+        \ 'args': (g:syntastic_javascript_jsl_conf != '' ? '-conf ' . g:syntastic_javascript_jsl_conf : ''),
         \ 'args_after': '-nologo -nofilelisting -nosummary -nocontext -process' })
 
     let errorformat =

syntax_checkers/limbo/limbo.vim

@@ -19,7 +19,7 @@ let s:save_cpo = &cpo
 set cpo&vim
 
 function! SyntaxCheckers_limbo_limbo_GetLocList() dict
-    let include = !empty($INFERNO_HOME) ? '-I$INFERNO_HOME ' : ''
+    let include = $INFERNO_HOME != '' ? '-I$INFERNO_HOME ' : ''
     " don't generate .dis in current dir while checking syntax,
     " .dis should be generated by `mk`
     let output = filereadable('mkfile') ? (' ' . syntastic#c#NullOutput()) : ''

syntax_checkers/lua/luac.vim

@@ -21,7 +21,7 @@ set cpo&vim
 function! SyntaxCheckers_lua_luac_GetHighlightRegex(pos)
     let result = ''
     let near = matchstr(a:pos['text'], '\mnear ''\zs[^'']\+\ze''')
-    if strlen(near) > 0
+    if near != ''
         if near ==# '<eof>'
             let p = getpos('$')
             let a:pos['lnum'] = p[1]
@@ -35,7 +35,7 @@ function! SyntaxCheckers_lua_luac_GetHighlightRegex(pos)
         " in future versions of syntastic; enable it at your own risk :)
 
         "let open = matchstr(a:pos['text'], '\m(to close ''\zs[^'']\+\ze'' at line [0-9]\+)')
-        "if strlen(open) > 0
+        "if open != ''
         "    let line = str2nr(matchstr(a:pos['text'], '\m(to close ''[^'']\+'' at line \zs[0-9]\+\ze)'))
         "    let group = a:pos['type'] ==? 'E' ? 'SyntasticError' : 'SyntasticWarning'
         "    call matchadd(group, '\%' . line . 'l\V' . open)

syntax_checkers/po/msgfmt.vim

@@ -20,7 +20,7 @@ set cpo&vim
 
 function! SyntaxCheckers_po_msgfmt_GetHighlightRegex(item)
     let term = matchstr(a:item['text'], '\mkeyword "\zs[^"]\+\ze" unknown')
-    return !empty(term) ? '\V' . term : ''
+    return term != '' ? '\V' . term : ''
 endfunction
 
 function! SyntaxCheckers_po_msgfmt_GetLocList() dict

syntax_checkers/sh/sh.vim

@@ -22,7 +22,7 @@ function! s:GetShell()
     if !exists('b:shell') || b:shell == ''
         let b:shell = ''
         let shebang = getbufline(bufnr('%'), 1)[0]
-        if strlen(shebang) > 0
+        if shebang != ''
             if stridx(shebang, 'bash') >= 0
                 let b:shell = 'bash'
             elseif stridx(shebang, 'zsh') >= 0

syntax_checkers/vala/valac.vim

@@ -36,8 +36,8 @@ let s:save_cpo = &cpo
 set cpo&vim
 
 function! SyntaxCheckers_vala_valac_GetHighlightRegex(pos)
-    let strlength = strlen(matchstr(a:pos['text'], '\m\^\+$'))
+    let length = strlen(matchstr(a:pos['text'], '\m\^\+$'))
-    return '\%>' . (a:pos.col-1) . 'c.*\%<' . (a:pos.col+strlength+1) . 'c'
+    return '\%>' . (a:pos['col'] - 1) . 'c.*\%<' . (a:pos['col'] + length + 1) . 'c'
 endfunction
 
 function! s:GetValaModules()