1" Vim plugin for showing matching parens
2" Maintainer:  Bram Moolenaar <[email protected]>
3" Last Change: 2008 Jan 06
4
5" Exit quickly when:
6" - this plugin was already loaded (or disabled)
7" - when 'compatible' is set
8" - the "CursorMoved" autocmd event is not availble.
9if exists("g:loaded_matchparen") || &cp || !exists("##CursorMoved")
10  finish
11endif
12let g:loaded_matchparen = 1
13
14augroup matchparen
15  " Replace all matchparen autocommands
16  autocmd! CursorMoved,CursorMovedI,WinEnter * call s:Highlight_Matching_Pair()
17augroup END
18
19" Skip the rest if it was already done.
20if exists("*s:Highlight_Matching_Pair")
21  finish
22endif
23
24let cpo_save = &cpo
25set cpo-=C
26
27" The function that is invoked (very often) to define a ":match" highlighting
28" for any matching paren.
29function! s:Highlight_Matching_Pair()
30  " Remove any previous match.
31  if exists('w:paren_hl_on') && w:paren_hl_on
32    3match none
33    let w:paren_hl_on = 0
34  endif
35
36  " Avoid that we remove the popup menu.
37  if pumvisible()
38    return
39  endif
40
41  " Get the character under the cursor and check if it's in 'matchpairs'.
42  let c_lnum = line('.')
43  let c_col = col('.')
44  let before = 0
45
46  let c = getline(c_lnum)[c_col - 1]
47  let plist = split(&matchpairs, '.\zs[:,]')
48  let i = index(plist, c)
49  if i < 0
50    " not found, in Insert mode try character before the cursor
51    if c_col > 1 && (mode() == 'i' || mode() == 'R')
52      let before = 1
53      let c = getline(c_lnum)[c_col - 2]
54      let i = index(plist, c)
55    endif
56    if i < 0
57      " not found, nothing to do
58      return
59    endif
60  endif
61
62  " Figure out the arguments for searchpairpos().
63  " Restrict the search to visible lines with "stopline".
64  " And avoid searching very far (e.g., for closed folds and long lines)
65  " The "viewable" variables give a range in which we can scroll while keeping
66  " the cursor at the same position
67  " adjustedScrolloff accounts for very large numbers of scrolloff
68  let adjustedScrolloff = min([&scrolloff, (line('w$') - line('w0')) / 2])
69  let bottom_viewable = min([line('$'), c_lnum + &lines - adjustedScrolloff - 2])
70  let top_viewable = max([1, c_lnum-&lines+adjustedScrolloff + 2])
71  " one of these stoplines will be adjusted below, but the current values are
72  " minimal boundaries within the current window
73  let stoplinebottom = line('w$')
74  let stoplinetop = line('w0')
75  if i % 2 == 0
76    let s_flags = 'nW'
77    let c2 = plist[i + 1]
78    if has("byte_offset") && has("syntax_items") && &smc > 0
79      let stopbyte = min([line2byte("$"), line2byte(".") + col(".") + &smc * 2])
80      let stopline = min([bottom_viewable, byte2line(stopbyte)])
81    else
82      let stopline = min([bottom_viewable, c_lnum + 100])
83    endif
84    let stoplinebottom = stopline
85  else
86    let s_flags = 'nbW'
87    let c2 = c
88    let c = plist[i - 1]
89    if has("byte_offset") && has("syntax_items") && &smc > 0
90      let stopbyte = max([1, line2byte(".") + col(".") - &smc * 2])
91      let stopline = max([top_viewable, byte2line(stopbyte)])
92    else
93      let stopline = max([top_viewable, c_lnum - 100])
94    endif
95    let stoplinetop = stopline
96  endif
97  if c == '['
98    let c = '\['
99    let c2 = '\]'
100  endif
101
102  " Find the match.  When it was just before the cursor move it there for a
103  " moment.
104  if before > 0
105    let save_cursor = winsaveview()
106    call cursor(c_lnum, c_col - before)
107  endif
108
109  " When not in a string or comment ignore matches inside them.
110  let s_skip ='synIDattr(synID(line("."), col("."), 0), "name") ' .
111	\ '=~?  "string\\|character\\|singlequote\\|comment"'
112  execute 'if' s_skip '| let s_skip = 0 | endif'
113
114  try
115    " Limit the search time to 500 msec to avoid a hang on very long lines.
116    let [m_lnum, m_col] = searchpairpos(c, '', c2, s_flags, s_skip, stopline, 500)
117  catch /E118/
118    let [m_lnum, m_col] = searchpairpos(c, '', c2, s_flags, s_skip, stopline)
119  endtry
120
121  if before > 0
122    call winrestview(save_cursor)
123  endif
124
125  " If a match is found setup match highlighting.
126  if m_lnum > 0 && m_lnum >= stoplinetop && m_lnum <= stoplinebottom
127    exe '3match MatchParen /\(\%' . c_lnum . 'l\%' . (c_col - before) .
128	  \ 'c\)\|\(\%' . m_lnum . 'l\%' . m_col . 'c\)/'
129    let w:paren_hl_on = 1
130  endif
131endfunction
132
133" Define commands that will disable and enable the plugin.
134command! NoMatchParen windo 3match none | unlet! g:loaded_matchparen |
135	  \ au! matchparen
136command! DoMatchParen runtime plugin/matchparen.vim | windo doau CursorMoved
137
138let &cpo = cpo_save
139