xref: /vim-8.2.3635/runtime/indent/json.vim (revision 6c391a74)
1" Vim indent file
2" Language:		JSON
3" Maintainer:		Eli Parra <[email protected]> https://github.com/elzr/vim-json
4" Last Change:          2020 Aug 30
5"   https://github.com/jakar/vim-json/commit/20b650e22aa750c4ab6a66aa646bdd95d7cd548a#diff-e81fc111b2052e306d126bd9989f7b7c
6" Original Author:	Rogerz Zhang <rogerz.zhang at gmail.com> http://github.com/rogerz/vim-json
7" Acknowledgement:      Based off of vim-javascript maintained by Darrick Wiebe
8"                       http://www.vim.org/scripts/script.php?script_id=2765
9
10" 0. Initialization {{{1
11" =================
12
13" Only load this indent file when no other was loaded.
14if exists("b:did_indent")
15  finish
16endif
17let b:did_indent = 1
18
19setlocal nosmartindent
20
21" Now, set up our indentation expression and keys that trigger it.
22setlocal indentexpr=GetJSONIndent(v:lnum)
23setlocal indentkeys=0{,0},0),0[,0],!^F,o,O,e
24
25" Only define the function once.
26if exists("*GetJSONIndent")
27  finish
28endif
29
30let s:cpo_save = &cpo
31set cpo&vim
32
33" 1. Variables {{{1
34" ============
35
36let s:line_term = '\s*\%(\%(\/\/\).*\)\=$'
37" Regex that defines blocks.
38let s:block_regex = '\%({\)\s*\%(|\%([*@]\=\h\w*,\=\s*\)\%(,\s*[*@]\=\h\w*\)*|\)\=' . s:line_term
39
40" 2. Auxiliary Functions {{{1
41" ======================
42
43" Check if the character at lnum:col is inside a string.
44function s:IsInString(lnum, col)
45  return synIDattr(synID(a:lnum, a:col, 1), 'name') == 'jsonString'
46endfunction
47
48" Find line above 'lnum' that isn't empty, or in a string.
49function s:PrevNonBlankNonString(lnum)
50  let lnum = prevnonblank(a:lnum)
51  while lnum > 0
52    " If the line isn't empty or in a string, end search.
53    let line = getline(lnum)
54    if !(s:IsInString(lnum, 1) && s:IsInString(lnum, strlen(line)))
55      break
56    endif
57    let lnum = prevnonblank(lnum - 1)
58  endwhile
59  return lnum
60endfunction
61
62" Check if line 'lnum' has more opening brackets than closing ones.
63function s:LineHasOpeningBrackets(lnum)
64  let open_0 = 0
65  let open_2 = 0
66  let open_4 = 0
67  let line = getline(a:lnum)
68  let pos = match(line, '[][(){}]', 0)
69  while pos != -1
70    let idx = stridx('(){}[]', line[pos])
71    if idx % 2 == 0
72      let open_{idx} = open_{idx} + 1
73    else
74      let open_{idx - 1} = open_{idx - 1} - 1
75    endif
76    let pos = match(line, '[][(){}]', pos + 1)
77  endwhile
78  return (open_0 > 0) . (open_2 > 0) . (open_4 > 0)
79endfunction
80
81function s:Match(lnum, regex)
82  let col = match(getline(a:lnum), a:regex) + 1
83  return col > 0 && !s:IsInString(a:lnum, col) ? col : 0
84endfunction
85
86" 3. GetJSONIndent Function {{{1
87" =========================
88
89function GetJSONIndent(...)
90  " 3.1. Setup {{{2
91  " ----------
92  " For the current line, use the first argument if given, else v:lnum
93  let clnum = a:0 ? a:1 : v:lnum
94
95  " Set up variables for restoring position in file.  Could use clnum here.
96  let vcol = col('.')
97
98  " 3.2. Work on the current line {{{2
99  " -----------------------------
100
101  " Get the current line.
102  let line = getline(clnum)
103  let ind = -1
104
105  " If we got a closing bracket on an empty line, find its match and indent
106  " according to it.
107  let col = matchend(line, '^\s*[]}]')
108
109  if col > 0 && !s:IsInString(clnum, col)
110    call cursor(clnum, col)
111    let bs = strpart('{}[]', stridx('}]', line[col - 1]) * 2, 2)
112
113    let pairstart = escape(bs[0], '[')
114    let pairend = escape(bs[1], ']')
115    let pairline = searchpair(pairstart, '', pairend, 'bW')
116
117    if pairline > 0
118      let ind = indent(pairline)
119    else
120      let ind = virtcol('.') - 1
121    endif
122
123    return ind
124  endif
125
126  " If we are in a multi-line string, don't do anything to it.
127  if s:IsInString(clnum, matchend(line, '^\s*') + 1)
128    return indent('.')
129  endif
130
131  " 3.3. Work on the previous line. {{{2
132  " -------------------------------
133
134  let lnum = prevnonblank(clnum - 1)
135
136  if lnum == 0
137    return 0
138  endif
139
140  " Set up variables for current line.
141  let line = getline(lnum)
142  let ind = indent(lnum)
143
144  " If the previous line ended with a block opening, add a level of indent.
145  " if s:Match(lnum, s:block_regex)
146    " return indent(lnum) + shiftwidth()
147  " endif
148
149  " If the previous line contained an opening bracket, and we are still in it,
150  " add indent depending on the bracket type.
151  if line =~ '[[({]'
152    let counts = s:LineHasOpeningBrackets(lnum)
153    if counts[0] == '1' || counts[1] == '1' || counts[2] == '1'
154      return ind + shiftwidth()
155    else
156      call cursor(clnum, vcol)
157    end
158  endif
159
160  " }}}2
161
162  return ind
163endfunction
164
165" }}}1
166
167let &cpo = s:cpo_save
168unlet s:cpo_save
169
170" vim:set sw=2 sts=2 ts=8 noet:
171