xref: /vim-8.2.3635/runtime/indent/tex.vim (revision eb3dc87f)
1" Vim indent file
2" Language:     LaTeX
3" Maintainer:   Yichao Zhou <broken.zhou AT gmail.com>
4" Created:      Sat, 16 Feb 2002 16:50:19 +0100
5" Version: 1.0.0
6"   Please email me if you found something I can do.  Comments, bug report and
7"   feature request are welcome.
8
9" Last Update:  {{{
10"               25th Sep 2002, by LH :
11"               (*) better support for the option
12"               (*) use some regex instead of several '||'.
13"               Oct 9th, 2003, by JT:
14"               (*) don't change indentation of lines starting with '%'
15"               2005/06/15, Moshe Kaminsky <kaminsky AT math.huji.ac.il>
16"               (*) New variables:
17"                   g:tex_items, g:tex_itemize_env, g:tex_noindent_env
18"               2011/3/6, by Yichao Zhou <broken.zhou AT gmail.com>
19"               (*) Don't change indentation of lines starting with '%'
20"                   I don't see any code with '%' and it doesn't work properly
21"                   so I add some code.
22"               (*) New features: Add smartindent-like indent for "{}" and  "[]".
23"               (*) New variables: g:tex_indent_brace
24"               2011/9/25, by Yichao Zhou <broken.zhou AT gmail.com>
25"               (*) Bug fix: smartindent-like indent for "[]"
26"               (*) New features: Align with "&".
27"               (*) New variable: g:tex_indent_and.
28"               2011/10/23 by Yichao Zhou <broken.zhou AT gmail.com>
29"               (*) Bug fix: improve the smartindent-like indent for "{}" and
30"               "[]".
31"               2012/02/27 by Yichao Zhou <broken.zhou AT gmail.com>
32"               (*) Bug fix: support default folding marker.
33"               (*) Indent with "&" is not very handy.  Make it not enable by
34"               default.
35"               2012/03/06 by Yichao Zhou <broken.zhou AT gmail.com>
36"               (*) Modify "&" behavior and make it default again.  Now "&"
37"               won't align when there are more then one "&" in the previous
38"               line.
39"               (*) Add indent "\left(" and "\right)"
40"               (*) Trust user when in "verbatim" and "lstlisting"
41"               2012/03/11 by Yichao Zhou <broken.zhou AT gmail.com>
42"               (*) Modify "&" so that only indent when current line start with
43"                   "&".
44"               2012/03/12 by Yichao Zhou <broken.zhou AT gmail.com>
45"               (*) Modify indentkeys.
46"               2012/03/18 by Yichao Zhou <broken.zhou AT gmail.com>
47"               (*) Add &cpo
48"               2013/05/02 by Yichao Zhou <broken.zhou AT gmail.com>
49"               (*) Fix problem about GetTeXIndent checker. Thank Albert Netymk
50"                   for reporting this.
51"               2014/06/23 by Yichao Zhou <broken.zhou AT gmail.com>
52"               (*) Remove the feature g:tex_indent_and because it is buggy.
53"               (*) If there is not any obvious indentation hints, we do not
54"                   alert our user's current indentation.
55"               (*) g:tex_indent_brace now only works if the open brace is the
56"                   last character of that line.
57"               2014/08/03 by Yichao Zhou <broken.zhou AT gmail.com>
58"               (*) Indent current line if last line has larger indentation
59"               2016/11/08 by Yichao Zhou <broken.zhou AT gmail.com>
60"               (*) Fix problems for \[ and \].  Thanks Bruno for reporting.
61"               2017/04/30 by Yichao Zhou <broken.zhou AT gmail.com>
62"               (*) Fix a bug between g:tex_noindent_env and g:tex_indent_items
63"                   Now g:tex_noindent_env='document\|verbatim\|itemize' (Emacs
64"                   style) is supported.  Thanks Miles Wheeler for reporting.
65"               2018/02/07 by Yichao Zhou <broken.zhou AT gmail.com>
66"               (*) Make indentation more smart in the normal mode
67"
68" }}}
69
70" Document: {{{
71"
72" To set the following options (ok, currently it's just one), add a line like
73"   let g:tex_indent_items = 1
74" to your ~/.vimrc.
75"
76" * g:tex_indent_brace
77"
78"   If this variable is unset or non-zero, it will use smartindent-like style
79"   for "{}" and "[]".  Now this only works if the open brace is the last
80"   character of that line.
81"
82"         % Example 1
83"         \usetikzlibrary{
84"           external
85"         }
86"
87"         % Example 2
88"         \tikzexternalize[
89"           prefix=tikz]
90"
91" * g:tex_indent_items
92"
93"   If this variable is set, item-environments are indented like Emacs does
94"   it, i.e., continuation lines are indented with a shiftwidth.
95"
96"              set                      unset
97"   ------------------------------------------------------
98"       \begin{itemize}            \begin{itemize}
99"         \item blablabla            \item blablabla
100"           bla bla bla              bla bla bla
101"         \item blablabla            \item blablabla
102"           bla bla bla              bla bla bla
103"       \end{itemize}              \end{itemize}
104"
105"
106" * g:tex_items
107"
108"   A list of tokens to be considered as commands for the beginning of an item
109"   command. The tokens should be separated with '\|'. The initial '\' should
110"   be escaped. The default is '\\bibitem\|\\item'.
111"
112" * g:tex_itemize_env
113"
114"   A list of environment names, separated with '\|', where the items (item
115"   commands matching g:tex_items) may appear. The default is
116"   'itemize\|description\|enumerate\|thebibliography'.
117"
118" * g:tex_noindent_env
119"
120"   A list of environment names. separated with '\|', where no indentation is
121"   required. The default is 'document\|verbatim'.
122" }}}
123
124" Only define the function once
125if exists("b:did_indent")
126    finish
127endif
128
129let s:cpo_save = &cpo
130set cpo&vim
131
132" Define global variable {{{
133
134let b:did_indent = 1
135
136if !exists("g:tex_indent_items")
137    let g:tex_indent_items = 1
138endif
139if !exists("g:tex_indent_brace")
140    let g:tex_indent_brace = 1
141endif
142if !exists("g:tex_max_scan_line")
143    let g:tex_max_scan_line = 60
144endif
145if g:tex_indent_items
146    if !exists("g:tex_itemize_env")
147        let g:tex_itemize_env = 'itemize\|description\|enumerate\|thebibliography'
148    endif
149    if !exists('g:tex_items')
150        let g:tex_items = '\\bibitem\|\\item'
151    endif
152else
153    let g:tex_items = ''
154endif
155
156if !exists("g:tex_noindent_env")
157    let g:tex_noindent_env = 'document\|verbatim\|lstlisting'
158endif "}}}
159
160" VIM Setting " {{{
161setlocal autoindent
162setlocal nosmartindent
163setlocal indentexpr=GetTeXIndent()
164setlocal indentkeys&
165exec 'setlocal indentkeys+=[,(,{,),},],\&' . substitute(g:tex_items, '^\|\(\\|\)', ',=', 'g')
166let g:tex_items = '^\s*' . substitute(g:tex_items, '^\(\^\\s\*\)*', '', '')
167" }}}
168
169function! GetTeXIndent() " {{{
170    " Find a non-blank line above the current line.
171    let lnum = prevnonblank(v:lnum - 1)
172    let cnum = v:lnum
173
174    " Comment line is not what we need.
175    while lnum != 0 && getline(lnum) =~ '^\s*%'
176        let lnum = prevnonblank(lnum - 1)
177    endwhile
178
179    " At the start of the file use zero indent.
180    if lnum == 0
181        return 0
182    endif
183
184    let line = substitute(getline(lnum), '\s*%.*', '','g')     " last line
185    let cline = substitute(getline(v:lnum), '\s*%.*', '', 'g') " current line
186
187    "  We are in verbatim, so do what our user what.
188    if synIDattr(synID(v:lnum, indent(v:lnum), 1), "name") == "texZone"
189        if empty(cline)
190            return indent(lnum)
191        else
192            return indent(v:lnum)
193        end
194    endif
195
196    if lnum == 0
197        return 0
198    endif
199
200    let ind = indent(lnum)
201    let stay = 1
202
203    " New code for comment: retain the indent of current line
204    if cline =~ '^\s*%'
205        return indent(v:lnum)
206    endif
207
208    " Add a 'shiftwidth' after beginning of environments.
209    " Don't add it for \begin{document} and \begin{verbatim}
210    " if line =~ '^\s*\\begin{\(.*\)}'  && line !~ 'verbatim'
211    " LH modification : \begin does not always start a line
212    " ZYC modification : \end after \begin won't cause wrong indent anymore
213    if line =~ '\\begin{.*}'
214        if line !~ g:tex_noindent_env
215            let ind = ind + shiftwidth()
216            let stay = 0
217        endif
218
219        if g:tex_indent_items
220            " Add another sw for item-environments
221            if line =~ g:tex_itemize_env
222                let ind = ind + shiftwidth()
223                let stay = 0
224            endif
225        endif
226    endif
227
228    if cline =~ '\\end{.*}'
229        let retn = s:GetEndIndentation(v:lnum)
230        if retn != -1
231            return retn
232        endif
233    end
234    " Subtract a 'shiftwidth' when an environment ends
235    if cline =~ '\\end{.*}'
236                \ && cline !~ g:tex_noindent_env
237                \ && cline !~ '\\begin{.*}.*\\end{.*}'
238        if g:tex_indent_items
239            " Remove another sw for item-environments
240            if cline =~ g:tex_itemize_env
241                let ind = ind - shiftwidth()
242                let stay = 0
243            endif
244        endif
245
246        let ind = ind - shiftwidth()
247        let stay = 0
248    endif
249
250    if g:tex_indent_brace
251        if line =~ '[[{]$'
252            let ind += shiftwidth()
253            let stay = 0
254        endif
255
256        if cline =~ '^\s*\\\?[\]}]' && s:CheckPairedIsLastCharacter(v:lnum, indent(v:lnum))
257            let ind -= shiftwidth()
258            let stay = 0
259        endif
260
261        if line !~ '^\s*\\\?[\]}]'
262            for i in range(indent(lnum)+1, strlen(line)-1)
263                let char = line[i]
264                if char == ']' || char == '}'
265                    if s:CheckPairedIsLastCharacter(lnum, i)
266                        let ind -= shiftwidth()
267                        let stay = 0
268                    endif
269                endif
270            endfor
271        endif
272    endif
273
274    " Special treatment for 'item'
275    " ----------------------------
276
277    if g:tex_indent_items
278        " '\item' or '\bibitem' itself:
279        if cline =~ g:tex_items
280            let ind = ind - shiftwidth()
281            let stay = 0
282        endif
283        " lines following to '\item' are intented once again:
284        if line =~ g:tex_items
285            let ind = ind + shiftwidth()
286            let stay = 0
287        endif
288    endif
289
290    if stay && mode() == 'i'
291        " If there is no obvious indentation hint, and indentation is triggered
292        " in insert mode, we trust our user.
293        if empty(cline)
294            return ind
295        else
296            return max([indent(v:lnum), s:GetLastBeginIndentation(v:lnum)])
297        endif
298    else
299        return ind
300    endif
301endfunction "}}}
302
303function! s:GetLastBeginIndentation(lnum) " {{{
304    let matchend = 1
305    for lnum in range(a:lnum-1, max([a:lnum - g:tex_max_scan_line, 1]), -1)
306        let line = getline(lnum)
307        if line =~ '\\end{.*}'
308            let matchend += 1
309        endif
310        if line =~ '\\begin{.*}'
311            let matchend -= 1
312        endif
313        if matchend == 0
314            if line =~ g:tex_noindent_env
315                return indent(lnum)
316            endif
317            if line =~ g:tex_itemize_env
318                return indent(lnum) + 2 * shiftwidth()
319            endif
320            return indent(lnum) + shiftwidth()
321        endif
322    endfor
323    return -1
324endfunction
325
326function! s:GetEndIndentation(lnum) " {{{
327    if getline(a:lnum) =~ '\\begin{.*}.*\\end{.*}'
328        return -1
329    endif
330
331    let min_indent = 100
332    let matchend = 1
333    for lnum in range(a:lnum-1, max([a:lnum-g:tex_max_scan_line, 1]), -1)
334        let line = getline(lnum)
335        if line =~ '\\end{.*}'
336            let matchend += 1
337        endif
338        if line =~ '\\begin{.*}'
339            let matchend -= 1
340        endif
341        if matchend == 0
342            return indent(lnum)
343        endif
344        if !empty(line)
345            let min_indent = min([min_indent, indent(lnum)])
346        endif
347    endfor
348    return min_indent - shiftwidth()
349endfunction
350
351" Most of the code is from matchparen.vim
352function! s:CheckPairedIsLastCharacter(lnum, col) "{{{
353    let c_lnum = a:lnum
354    let c_col = a:col+1
355
356    let line = getline(c_lnum)
357    if line[c_col-1] == '\'
358        let c_col = c_col + 1
359    endif
360    let c = line[c_col-1]
361
362    let plist = split(&matchpairs, '.\zs[:,]')
363    let i = index(plist, c)
364    if i < 0
365        return 0
366    endif
367
368    " Figure out the arguments for searchpairpos().
369    if i % 2 == 0
370        let s_flags = 'nW'
371        let c2 = plist[i + 1]
372    else
373        let s_flags = 'nbW'
374        let c2 = c
375        let c = plist[i - 1]
376    endif
377    if c == '['
378        let c = '\['
379        let c2 = '\]'
380    endif
381
382    " Find the match.  When it was just before the cursor move it there for a
383    " moment.
384    let save_cursor = winsaveview()
385    call cursor(c_lnum, c_col)
386
387    " When not in a string or comment ignore matches inside them.
388    " We match "escape" for special items, such as lispEscapeSpecial.
389    let s_skip ='synIDattr(synID(line("."), col("."), 0), "name") ' .
390                \ '=~?  "string\\|character\\|singlequote\\|escape\\|comment"'
391    execute 'if' s_skip '| let s_skip = 0 | endif'
392
393    let stopline = max([0, c_lnum - g:tex_max_scan_line])
394
395    " Limit the search time to 300 msec to avoid a hang on very long lines.
396    " This fails when a timeout is not supported.
397    try
398        let [m_lnum, m_col] = searchpairpos(c, '', c2, s_flags, s_skip, stopline, 100)
399    catch /E118/
400    endtry
401
402    call winrestview(save_cursor)
403
404    if m_lnum > 0
405        let line = getline(m_lnum)
406        return strlen(line) == m_col
407    endif
408
409    return 0
410endfunction "}}}
411
412let &cpo = s:cpo_save
413unlet s:cpo_save
414
415" vim: set sw=4 textwidth=80:
416