1" Vim indent file
2" Language: Javascript
3" Maintainer: Chris Paul ( https://github.com/bounceme )
4" URL: https://github.com/pangloss/vim-javascript
5" Last Change: December 31, 2016
6
7" Only load this indent file when no other was loaded.
8if exists('b:did_indent')
9  finish
10endif
11let b:did_indent = 1
12
13" Now, set up our indentation expression and keys that trigger it.
14setlocal indentexpr=GetJavascriptIndent()
15setlocal autoindent nolisp nosmartindent
16setlocal indentkeys+=0],0)
17
18let b:undo_indent = 'setlocal indentexpr< smartindent< autoindent< indentkeys<'
19
20" Only define the function once.
21if exists('*GetJavascriptIndent')
22  finish
23endif
24
25let s:cpo_save = &cpo
26set cpo&vim
27
28" Get shiftwidth value
29if exists('*shiftwidth')
30  function s:sw()
31    return shiftwidth()
32  endfunction
33else
34  function s:sw()
35    return &sw
36  endfunction
37endif
38
39" searchpair() wrapper
40if has('reltime')
41  function s:GetPair(start,end,flags,skip,time,...)
42    return searchpair('\m'.a:start,'','\m'.a:end,a:flags,a:skip,max([prevnonblank(v:lnum) - 2000,0] + a:000),a:time)
43  endfunction
44else
45  function s:GetPair(start,end,flags,skip,...)
46    return searchpair('\m'.a:start,'','\m'.a:end,a:flags,a:skip,max([prevnonblank(v:lnum) - 1000,get(a:000,1)]))
47  endfunction
48endif
49
50" Regex of syntax group names that are or delimit string or are comments.
51let s:syng_strcom = 'string\|comment\|regex\|special\|doc\|template'
52let s:syng_str = 'string\|template'
53let s:syng_com = 'comment\|doc'
54" Expression used to check whether we should skip a match with searchpair().
55let s:skip_expr = "synIDattr(synID(line('.'),col('.'),0),'name') =~? '".s:syng_strcom."'"
56
57function s:skip_func()
58  if !s:free || search('\m`\|\*\/','nW',s:looksyn)
59    let s:free = !eval(s:skip_expr)
60    let s:looksyn = s:free ? line('.') : s:looksyn
61    return !s:free
62  endif
63  let s:looksyn = line('.')
64  return (search('\m\/','nbW',s:looksyn) || search('\m[''"]\|\\$','nW',s:looksyn)) && eval(s:skip_expr)
65endfunction
66
67function s:alternatePair(stop)
68  let pos = getpos('.')[1:2]
69  while search('\m[][(){}]','bW',a:stop)
70    if !s:skip_func()
71      let idx = stridx('])}',s:looking_at())
72      if idx + 1
73        if !s:GetPair(['\[','(','{'][idx], '])}'[idx],'bW','s:skip_func()',2000,a:stop)
74          break
75        endif
76      else
77        return
78      endif
79    endif
80  endwhile
81  call call('cursor',pos)
82endfunction
83
84function s:save_pos(f,...)
85  let l:pos = getpos('.')[1:2]
86  let ret = call(a:f,a:000)
87  call call('cursor',l:pos)
88  return ret
89endfunction
90
91function s:syn_at(l,c)
92  return synIDattr(synID(a:l,a:c,0),'name')
93endfunction
94
95function s:looking_at()
96  return getline('.')[col('.')-1]
97endfunction
98
99function s:token()
100  return s:looking_at() =~ '\k' ? expand('<cword>') : s:looking_at()
101endfunction
102
103function s:b_token()
104  if s:looking_at() =~ '\k'
105    call search('\m\<','cbW')
106  endif
107  return search('\m\S','bW')
108endfunction
109
110function s:previous_token()
111  let l:n = line('.')
112  while s:b_token()
113    if (s:looking_at() == '/' || line('.') != l:n && search('\m\/\/','nbW',
114          \ line('.'))) && s:syn_at(line('.'),col('.')) =~? s:syng_com
115      call search('\m\_[^/]\zs\/[/*]','bW')
116    else
117      return s:token()
118    endif
119  endwhile
120  return ''
121endfunction
122
123function s:others(p)
124  return "((line2byte(line('.')) + col('.')) <= ".(line2byte(a:p[0]) + a:p[1]).") || ".s:skip_expr
125endfunction
126
127function s:tern_skip(p)
128  return s:GetPair('{','}','nbW',s:others(a:p),200,a:p[0]) > 0
129endfunction
130
131function s:tern_col(p)
132  return s:GetPair('?',':\@<!::\@!','nbW',s:others(a:p)
133        \ .' || s:tern_skip('.string(a:p).')',200,a:p[0]) > 0
134endfunction
135
136function s:label_col()
137  let pos = getpos('.')[1:2]
138  let [s:looksyn,s:free] = pos
139  call s:alternatePair(0)
140  if s:save_pos('s:IsBlock')
141    let poss = getpos('.')[1:2]
142    return call('cursor',pos) || !s:tern_col(poss)
143  elseif s:looking_at() == ':'
144    return !s:tern_col([0,0])
145  endif
146endfunction
147
148" configurable regexes that define continuation lines, not including (, {, or [.
149let s:opfirst = '^' . get(g:,'javascript_opfirst',
150      \ '\%([<>=,?^%|*/&]\|\([-.:+]\)\1\@!\|!=\|in\%(stanceof\)\=\>\)')
151let s:continuation = get(g:,'javascript_continuation',
152      \ '\%([<=,.~!?/*^%|&:]\|+\@<!+\|-\@<!-\|=\@<!>\|\<\%(typeof\|delete\|void\|in\|instanceof\)\)') . '$'
153
154function s:continues(ln,con)
155  return !cursor(a:ln, match(' '.a:con,s:continuation)) &&
156        \ eval((['s:syn_at(line("."),col(".")) !~? "regex"'] +
157        \ repeat(['s:previous_token() != "."'],5) + [1])[
158        \ index(split('/ typeof in instanceof void delete'),s:token())])
159endfunction
160
161" get the line of code stripped of comments and move cursor to the last
162" non-comment char.
163function s:Trim(ln)
164  let pline = substitute(getline(a:ln),'\s*$','','')
165  let l:max = max([match(pline,'.*[^/]\zs\/[/*]'),0])
166  while l:max && s:syn_at(a:ln, strlen(pline)) =~? s:syng_com
167    let pline = substitute(strpart(pline, 0, l:max),'\s*$','','')
168    let l:max = max([match(pline,'.*[^/]\zs\/[/*]'),0])
169  endwhile
170  return cursor(a:ln,strlen(pline)) ? pline : pline
171endfunction
172
173" Find line above 'lnum' that isn't empty or in a comment
174function s:PrevCodeLine(lnum)
175  let l:n = prevnonblank(a:lnum)
176  while l:n
177    if getline(l:n) =~ '^\s*\/[/*]'
178      if (stridx(getline(l:n),'`') > 0 || getline(l:n-1)[-1:] == '\') &&
179            \ s:syn_at(l:n,1) =~? s:syng_str
180        return l:n
181      endif
182      let l:n = prevnonblank(l:n-1)
183    elseif s:syn_at(l:n,1) =~? s:syng_com
184      let l:n = s:save_pos('eval',
185            \ 'cursor('.l:n.',1) + search(''\m\/\*'',"bW")')
186    else
187      return l:n
188    endif
189  endwhile
190endfunction
191
192" Check if line 'lnum' has a balanced amount of parentheses.
193function s:Balanced(lnum)
194  let l:open = 0
195  let l:line = getline(a:lnum)
196  let pos = match(l:line, '[][(){}]', 0)
197  while pos != -1
198    if s:syn_at(a:lnum,pos + 1) !~? s:syng_strcom
199      let l:open += match(' ' . l:line[pos],'[[({]')
200      if l:open < 0
201        return
202      endif
203    endif
204    let pos = match(l:line, '[][(){}]', pos + 1)
205  endwhile
206  return !l:open
207endfunction
208
209function s:OneScope(lnum)
210  let pline = s:Trim(a:lnum)
211  let kw = 'else do'
212  if pline[-1:] == ')' && s:GetPair('(', ')', 'bW', s:skip_expr, 100) > 0
213    call s:previous_token()
214    let kw = 'for if let while with'
215    if index(split('await each'),s:token()) + 1
216      call s:previous_token()
217      let kw = 'for'
218    endif
219  endif
220  return pline[-2:] == '=>' || index(split(kw),s:token()) + 1 &&
221        \ s:save_pos('s:previous_token') != '.'
222endfunction
223
224" returns braceless levels started by 'i' and above lines * &sw. 'num' is the
225" lineNr which encloses the entire context, 'cont' if whether line 'i' + 1 is
226" a continued expression, which could have started in a braceless context
227function s:iscontOne(i,num,cont)
228  let [l:i, l:num, bL] = [a:i, a:num + !a:num, 0]
229  let pind = a:num ? indent(l:num) + s:W : 0
230  let ind = indent(l:i) + (a:cont ? 0 : s:W)
231  while l:i >= l:num && (ind > pind || l:i == l:num)
232    if indent(l:i) < ind && s:OneScope(l:i)
233      let bL += s:W
234      let l:i = line('.')
235    elseif !a:cont || bL || ind < indent(a:i)
236      break
237    endif
238    let ind = min([ind, indent(l:i)])
239    let l:i = s:PrevCodeLine(l:i - 1)
240  endwhile
241  return bL
242endfunction
243
244" https://github.com/sweet-js/sweet.js/wiki/design#give-lookbehind-to-the-reader
245function s:IsBlock()
246  if s:looking_at() == '{'
247    let l:n = line('.')
248    let char = s:previous_token()
249    let syn = char =~ '[{>/]' ? s:syn_at(line('.'),col('.')-(char == '{')) : ''
250    if syn =~? 'xml\|jsx'
251      return char != '{'
252    elseif char =~ '\k'
253      return index(split('return const let import export yield default delete var await void typeof throw case new in instanceof')
254            \ ,char) < (line('.') != l:n) || s:previous_token() == '.'
255    elseif char == '>'
256      return getline('.')[col('.')-2] == '=' || syn =~? '^jsflow'
257    elseif char == ':'
258      return getline('.')[col('.')-2] != ':' && s:label_col()
259    endif
260    return syn =~? 'regex' || char !~ '[-=~!<*+,/?^%|&([]'
261  endif
262endfunction
263
264function GetJavascriptIndent()
265  let b:js_cache = get(b:,'js_cache',[0,0,0])
266  " Get the current line.
267  call cursor(v:lnum,1)
268  let l:line = getline('.')
269  let syns = s:syn_at(v:lnum, 1)
270
271  " start with strings,comments,etc.
272  if syns =~? s:syng_com
273    if l:line =~ '^\s*\*'
274      return cindent(v:lnum)
275    elseif l:line !~ '^\s*\/[/*]'
276      return -1
277    endif
278  elseif syns =~? s:syng_str && l:line !~ '^[''"]'
279    if b:js_cache[0] == v:lnum - 1 && s:Balanced(v:lnum-1)
280      let b:js_cache[0] = v:lnum
281    endif
282    return -1
283  endif
284  let l:lnum = s:PrevCodeLine(v:lnum - 1)
285  if !l:lnum
286    return
287  endif
288
289  let l:line = substitute(l:line,'^\s*','','')
290  if l:line[:1] == '/*'
291    let l:line = substitute(l:line,'^\%(\/\*.\{-}\*\/\s*\)*','','')
292  endif
293  if l:line =~ '^\/[/*]'
294    let l:line = ''
295  endif
296
297  " the containing paren, bracket, or curly. Many hacks for performance
298  let idx = strlen(l:line) ? stridx('])}',l:line[0]) : -1
299  if b:js_cache[0] >= l:lnum && b:js_cache[0] < v:lnum &&
300        \ (b:js_cache[0] > l:lnum || s:Balanced(l:lnum))
301    call call('cursor',b:js_cache[1:])
302  else
303    let [s:looksyn, s:free, top] = [v:lnum - 1, 1, (!indent(l:lnum) &&
304          \ s:syn_at(l:lnum,1) !~? s:syng_str) * l:lnum]
305    if idx + 1
306      call s:GetPair(['\[','(','{'][idx], '])}'[idx],'bW','s:skip_func()',2000,top)
307    elseif indent(v:lnum) && syns =~? 'block'
308      call s:GetPair('{','}','bW','s:skip_func()',2000,top)
309    else
310      call s:alternatePair(top)
311    endif
312  endif
313
314  if idx + 1 || l:line[:1] == '|}'
315    if idx == 2 && search('\m\S','bW',line('.')) && s:looking_at() == ')'
316      call s:GetPair('(',')','bW',s:skip_expr,200)
317    endif
318    return indent('.')
319  endif
320
321  let b:js_cache = [v:lnum] + (line('.') == v:lnum ? [0,0] : getpos('.')[1:2])
322  let num = b:js_cache[1]
323
324  let [s:W, isOp, bL, switch_offset] = [s:sw(),0,0,0]
325  if !num || s:IsBlock()
326    let pline = s:save_pos('s:Trim',l:lnum)
327    if num && s:looking_at() == ')' && s:GetPair('(', ')', 'bW', s:skip_expr, 100) > 0
328      let num = line('.')
329      if s:previous_token() ==# 'switch' && s:previous_token() != '.'
330        if &cino !~ ':' || !has('float')
331          let switch_offset = s:W
332        else
333          let cinc = matchlist(&cino,'.*:\(-\)\=\([0-9.]*\)\(s\)\=\C')
334          let switch_offset = float2nr(str2float(cinc[1].(strlen(cinc[2]) ? cinc[2] : strlen(cinc[3])))
335                \ * (strlen(cinc[3]) ? s:W : 1))
336        endif
337        if pline[-1:] != '.' && l:line =~# '^\%(default\|case\)\>'
338          return indent(num) + switch_offset
339        endif
340      endif
341    endif
342    if pline[-1:] !~ '[{;]'
343      if pline =~# ':\@<!:$'
344        call cursor(l:lnum,strlen(pline))
345        let isOp = s:tern_col(b:js_cache[1:2])
346      else
347        let isOp = l:line =~# s:opfirst || s:continues(l:lnum,pline)
348      endif
349      let bL = s:iscontOne(l:lnum,num,isOp)
350      let bL -= (bL && l:line[0] == '{') * s:W
351    endif
352  endif
353
354  " main return
355  if isOp
356    return (num ? indent(num) : -s:W) + (s:W * 2) + switch_offset + bL
357  elseif num
358    return indent(num) + s:W + switch_offset + bL
359  endif
360  return bL
361endfunction
362
363let &cpo = s:cpo_save
364unlet s:cpo_save
365