Add width controls to the new stl_format flags.

autoload/syntastic/util.vim

@@ -107,16 +107,16 @@ function! syntastic#util#rmrf(what) abort " {{{2
     endif
 endfunction " }}}2
 
-"search the first 5 lines of the file for a magic number and return a map
+" Search the first 5 lines of the file for a magic number and return a map
-"containing the args and the executable
+" containing the args and the executable
 "
-"e.g.
+" e.g.
 "
-"#!/usr/bin/perl -f -bar
+" #!/usr/bin/perl -f -bar
 "
-"returns
+" returns
 "
-"{'exe': '/usr/bin/perl', 'args': ['-f', '-bar']}
+" {'exe': '/usr/bin/perl', 'args': ['-f', '-bar']}
 function! syntastic#util#parseShebang() abort " {{{2
     for lnum in range(1, 5)
         let line = getline(lnum)
@@ -183,7 +183,7 @@ function! syntastic#util#screenWidth(str, tabstop) abort " {{{2
     return width
 endfunction " }}}2
 
-"print as much of a:msg as possible without "Press Enter" prompt appearing
+" Print as much of a:msg as possible without "Press Enter" prompt appearing
 function! syntastic#util#wideMsg(msg) abort " {{{2
     let old_ruler = &ruler
     let old_showcmd = &showcmd
@@ -226,7 +226,7 @@ function! syntastic#util#bufIsActive(buffer) abort " {{{2
     return 0
 endfunction " }}}2
 
-" start in directory a:where and walk up the parent folders until it finds a
+" Start in directory a:where and walk up the parent folders until it finds a
 " file named a:what; return path to that file
 function! syntastic#util#findFileInParent(what, where) abort " {{{2
     let old_suffixesadd = &suffixesadd
@@ -236,7 +236,7 @@ function! syntastic#util#findFileInParent(what, where) abort " {{{2
     return file
 endfunction " }}}2
 
-" start in directory a:where and walk up the parent folders until it finds a
+" Start in directory a:where and walk up the parent folders until it finds a
 " file matching a:what; return path to that file
 function! syntastic#util#findGlobInParent(what, where) abort " {{{2
     let here = fnamemodify(a:where, ':p')
@@ -303,7 +303,7 @@ function! syntastic#util#argsescape(opt) abort " {{{2
     return []
 endfunction " }}}2
 
-" decode XML entities
+" Decode XML entities
 function! syntastic#util#decodeXMLEntities(string) abort " {{{2
     let str = a:string
     let str = substitute(str, '\m&lt;', '<', 'g')
@@ -350,6 +350,64 @@ function! syntastic#util#float2str(val) abort " {{{2
     return s:_float2str(a:val)
 endfunction " }}}2
 
+" Crude printf()-like width formatter.  Handles wide characters.
+function! syntastic#util#wformat(format, str) abort " {{{2
+    if a:format ==# ''
+        return a:str
+    endif
+
+ echomsg string(a:format) . ', ' . string(a:str)
+    let specs = matchlist(a:format, '\v^(-?)(0?)(%([1-9]\d*))?%(\.(\d+))?$')
+    if len(specs) < 5
+        return a:str
+    endif
+
+    let flushleft = specs[1] ==# '-'
+    let lpad = specs[2] ==# '0' ? '0' : ' '
+    let minlen = str2nr(specs[3])
+    let maxlen = str2nr(specs[4])
+    let out = substitute(a:str, "\t", ' ', 'g')
+
+    if maxlen && s:_width(out) > maxlen
+        let chars = filter(split(a:str, '\zs\ze', 1), 'v:val !=# ""')
+        let totlen = 0
+        let out = ''
+
+        if flushleft
+            for c in chars
+                if totlen + s:_width(c) < maxlen
+                    let out .= c
+                    let totlen += s:_width(c)
+                else
+                    let out .= &encoding ==# 'utf-8' && &termencoding ==# 'utf-8' ? "\u2026" : '>'
+                    break
+                endif
+            endfor
+        else
+            call reverse(chars)
+            for c in chars
+                if totlen + s:_width(c) < maxlen
+                    let out = c . out
+                    let totlen += s:_width(c)
+                else
+                    let out = (&encoding ==# 'utf-8' && &termencoding ==# 'utf-8' ? "\u2026" : '<') . out
+                    break
+                endif
+            endfor
+        endif
+    endif
+
+    if minlen && s:_width(out) < minlen
+        if flushleft
+            let out .= repeat(' ', minlen - s:_width(out))
+        else
+            let out = repeat(lpad, minlen - s:_width(out)) . out
+        endif
+    endif
+
+    return out
+endfunction " }}}2
+
 " }}}1
 
 " Private functions {{{1

doc/syntastic.txt

@@ -585,6 +585,13 @@ magic flags are available to insert information:
     %fw - line number of first warning
     %F  - line number of first warning or error
 
+These flags accept width and alignment controls similar to the ones used by
+|'statusline'| flags:
+    %-0{minwid}.{maxwid}{flag}
+
+All fields except {flag} are optional. A single percent sign can be given as
+"%%".
+
 Several additional flags are available to hide text under certain conditions:
     %E{...} - hide the text in the brackets unless there are errors
     %W{...} - hide the text in the brackets unless there are warnings

plugin/syntastic.vim

@@ -19,7 +19,7 @@ if has('reltime')
     lockvar! g:_SYNTASTIC_START
 endif
 
-let g:_SYNTASTIC_VERSION = '3.6.0-170'
+let g:_SYNTASTIC_VERSION = '3.6.0-171'
 lockvar g:_SYNTASTIC_VERSION
 
 " Sanity checks {{{1

plugin/syntastic/loclist.vim

@@ -111,6 +111,7 @@ function! g:SyntasticLoclist.getStatuslineFlag() abort " {{{2
             let output = substitute(output, '\m\C%B{\([^}]*\)}', (num_warnings && num_errors) ? '\1' : '' , 'g')
 
             let flags = {
+                \ '%':  '%',
                 \ 't':  num_issues,
                 \ 'e':  num_errors,
                 \ 'w':  num_warnings,
@@ -123,7 +124,7 @@ function! g:SyntasticLoclist.getStatuslineFlag() abort " {{{2
                 \ 'nw': (num_warnings ? fnamemodify( bufname(warnings[0]['bufnr']), ':t') : ''),
                 \ 'pw': (num_warnings ? fnamemodify( bufname(warnings[0]['bufnr']), ':p:~:.') : ''),
                 \ 'fw': (num_warnings ? warnings[0]['lnum'] : '') }
-            let output = substitute(output, '\v\C\%([npf][ew]|[NPFtew])', '\=flags[submatch(1)]', 'g')
+            let output = substitute(output, '\v\C\%(-?\d*%(\.\d+)?)([npf][ew]|[NPFtew%])', '\=syntastic#util#wformat(submatch(1), flags[submatch(2)])', 'g')
 
             let self._stl_flag = output
         else