xref: /vim-8.2.3635/runtime/indent/xml.vim (revision 23515b4e)
1" Language: XML
2" Maintainer: Christian Brabandt <[email protected]>
3" Repository: https://github.com/chrisbra/vim-xml-ftplugin
4" Previous Maintainer: Johannes Zellner <[email protected]>
5" Last Changed: 2020 Nov 4th
6" Last Change:
7" 20200529 - Handle empty closing tags correctly
8" 20191202 - Handle docbk filetype
9" 20190726 - Correctly handle non-tagged data
10" 20190204 - correctly handle wrap tags
11"            https://github.com/chrisbra/vim-xml-ftplugin/issues/5
12" 20190128 - Make sure to find previous tag
13"            https://github.com/chrisbra/vim-xml-ftplugin/issues/4
14" 20181116 - Fix indentation when tags start with a colon or an underscore
15"            https://github.com/vim/vim/pull/926
16" 20181022 - Do not overwrite indentkeys setting
17"            https://github.com/chrisbra/vim-xml-ftplugin/issues/1
18" 20180724 - Correctly indent xml comments https://github.com/vim/vim/issues/3200
19"
20" Notes:
21"   1) does not indent pure non-xml code (e.g. embedded scripts)
22"       2) will be confused by unbalanced tags in comments
23"       or CDATA sections.
24"       2009-05-26 patch by Nikolai Weibull
25" TODO:     implement pre-like tags, see xml_indent_open / xml_indent_close
26
27" Only load this indent file when no other was loaded.
28if exists("b:did_indent")
29    finish
30endif
31let b:did_indent = 1
32let s:keepcpo= &cpo
33set cpo&vim
34
35" [-- local settings (must come before aborting the script) --]
36" Attention: Parameter use_syntax_check is used by the docbk.vim indent script
37setlocal indentexpr=XmlIndentGet(v:lnum,1)
38setlocal indentkeys=o,O,*<Return>,<>>,<<>,/,{,},!^F
39" autoindent: used when the indentexpr returns -1
40setlocal autoindent
41
42if !exists('b:xml_indent_open')
43    let b:xml_indent_open = '.\{-}<[:A-Z_a-z]'
44    " pre tag, e.g. <address>
45    " let b:xml_indent_open = '.\{-}<[/]\@!\(address\)\@!'
46endif
47
48if !exists('b:xml_indent_close')
49    let b:xml_indent_close = '.\{-}</\|/>.\{-}'
50    " end pre tag, e.g. </address>
51    " let b:xml_indent_close = '.\{-}</\(address\)\@!'
52endif
53
54let &cpo = s:keepcpo
55unlet s:keepcpo
56
57" [-- finish, if the function already exists --]
58if exists('*XmlIndentGet')
59    finish
60endif
61
62let s:keepcpo= &cpo
63set cpo&vim
64
65fun! <SID>XmlIndentWithPattern(line, pat)
66    let s = substitute('x'.a:line, a:pat, "\1", 'g')
67    return strlen(substitute(s, "[^\1].*$", '', ''))
68endfun
69
70" [-- check if it's xml --]
71fun! <SID>XmlIndentSynCheck(lnum)
72    if &syntax != ''
73        let syn1 = synIDattr(synID(a:lnum, 1, 1), 'name')
74        let syn2 = synIDattr(synID(a:lnum, strlen(getline(a:lnum)) - 1, 1), 'name')
75        if syn1 != '' && syn1 !~ 'xml' && syn2 != '' && syn2 !~ 'xml'
76            " don't indent pure non-xml code
77            return 0
78        endif
79    endif
80    return 1
81endfun
82
83" [-- return the sum of indents of a:lnum --]
84fun! <SID>XmlIndentSum(line, style, add)
85    if <SID>IsXMLContinuation(a:line) && a:style == 0 && !<SID>IsXMLEmptyClosingTag(a:line)
86        " no complete tag, add one additional indent level
87        " but only for the current line
88        return a:add + shiftwidth()
89    elseif <SID>HasNoTagEnd(a:line)
90        " no complete tag, return initial indent
91        return a:add
92    endif
93    if a:style == match(a:line, '^\s*</')
94        return (shiftwidth() *
95        \  (<SID>XmlIndentWithPattern(a:line, b:xml_indent_open)
96        \ - <SID>XmlIndentWithPattern(a:line, b:xml_indent_close)
97        \ - <SID>XmlIndentWithPattern(a:line, '.\{-}/>'))) + a:add
98    else
99        return a:add
100    endif
101endfun
102
103" Main indent function
104fun! XmlIndentGet(lnum, use_syntax_check)
105    " Find a non-empty line above the current line.
106    if prevnonblank(a:lnum - 1) == 0
107        " Hit the start of the file, use zero indent.
108        return 0
109    endif
110    " Find previous line with a tag (regardless whether open or closed,
111    " but always restrict the match to a line before the current one
112    " Note: xml declaration: <?xml version="1.0"?>
113    "       won't be found, as it is not a legal tag name
114    let ptag_pattern = '\%(.\{-}<[/:A-Z_a-z]\)'. '\%(\&\%<'. a:lnum .'l\)'
115    let ptag = search(ptag_pattern, 'bnW')
116    " no previous tag
117    if ptag == 0
118        return 0
119    endif
120
121    let pline = getline(ptag)
122    let pind  = indent(ptag)
123
124    let syn_name_start = '' " Syntax element at start of line (excluding whitespace)
125    let syn_name_end = ''   " Syntax element at end of line
126    let curline = getline(a:lnum)
127    if a:use_syntax_check
128        let check_lnum = <SID>XmlIndentSynCheck(ptag)
129        let check_alnum = <SID>XmlIndentSynCheck(a:lnum)
130        if check_lnum == 0 || check_alnum == 0
131            return indent(a:lnum)
132        endif
133        let syn_name_end   = synIDattr(synID(a:lnum, strlen(curline) - 1, 1), 'name')
134        let syn_name_start = synIDattr(synID(a:lnum, match(curline, '\S') + 1, 1), 'name')
135        let prev_syn_name_end   = synIDattr(synID(ptag, strlen(pline) - 1, 1), 'name')
136        " not needed (yet?)
137        " let prev_syn_name_start = synIDattr(synID(ptag, match(pline, '\S') + 1, 1), 'name')
138    endif
139
140    if syn_name_end =~ 'Comment' && syn_name_start =~ 'Comment'
141        return <SID>XmlIndentComment(a:lnum)
142    elseif empty(syn_name_start) && empty(syn_name_end) && a:use_syntax_check
143        " non-xml tag content: use indent from 'autoindent'
144        if pline =~ b:xml_indent_close
145            return pind
146        elseif !empty(prev_syn_name_end)
147            " only indent by an extra shiftwidth, if the previous line ends
148            " with an XML like tag
149           return pind + shiftwidth()
150        else
151            " no extra indent, looks like a text continuation line
152           return pind
153        endif
154    endif
155
156    " Get indent from previous tag line
157    let ind = <SID>XmlIndentSum(pline, -1, pind)
158    " Determine indent from current line
159    let ind = <SID>XmlIndentSum(curline, 0, ind)
160    return ind
161endfun
162
163func! <SID>IsXMLContinuation(line)
164    " Checks, whether or not the line matches a start-of-tag
165    return a:line !~ '^\s*<' && &ft is# 'xml'
166endfunc
167
168func! <SID>HasNoTagEnd(line)
169    " Checks whether or not the line matches '>' (so finishes a tag)
170    return a:line !~ '>\s*$'
171endfunc
172
173func! <SID>IsXMLEmptyClosingTag(line)
174    " Checks whether the line ends with an empty closing tag such as <lb/>
175    return a:line =~? '<[^>]*/>\s*$'
176endfunc
177
178" return indent for a commented line,
179" the middle part might be indented one additional level
180func! <SID>XmlIndentComment(lnum)
181    let ptagopen = search('.\{-}<[:A-Z_a-z]\_[^/]\{-}>.\{-}', 'bnW')
182    let ptagclose = search(b:xml_indent_close, 'bnW')
183    if getline(a:lnum) =~ '<!--'
184        " if previous tag was a closing tag, do not add
185        " one additional level of indent
186        if ptagclose > ptagopen && a:lnum > ptagclose
187            " If the previous tag was closed on the same line as it was
188            " declared, we should indent with its indent level.
189            if !<SID>IsXMLContinuation(getline(ptagclose))
190                return indent(ptagclose)
191            else
192                return indent(ptagclose) - shiftwidth()
193            endif
194        elseif ptagclose == ptagopen
195            return indent(ptagclose)
196        else
197            " start of comment, add one indentation level
198            return indent(ptagopen) + shiftwidth()
199        endif
200    elseif getline(a:lnum) =~ '-->'
201        " end of comment, same as start of comment
202        return indent(search('<!--', 'bnW'))
203    else
204        " middle part of comment, add one additional level
205        return indent(search('<!--', 'bnW')) + shiftwidth()
206    endif
207endfunc
208
209let &cpo = s:keepcpo
210unlet s:keepcpo
211
212" vim:ts=4 et sts=-1 sw=0
213