xref: /vim-8.2.3635/runtime/indent/xml.vim (revision fcfe1a9b)
1"     Language: xml
2"   Repository: https://github.com/chrisbra/vim-xml-ftplugin
3" Last Changed: July 27, 2019
4"   Maintainer: Christian Brabandt <[email protected]>
5" Previous Maintainer:  Johannes Zellner <[email protected]>
6" Last Change:
7" 20190726 - Correctly handle non-tagged data
8" 20190204 - correctly handle wrap tags
9"            https://github.com/chrisbra/vim-xml-ftplugin/issues/5
10" 20190128 - Make sure to find previous tag
11"            https://github.com/chrisbra/vim-xml-ftplugin/issues/4
12" 20181116 - Fix indentation when tags start with a colon or an underscore
13"            https://github.com/vim/vim/pull/926
14" 20181022 - Do not overwrite indentkeys setting
15"            https://github.com/chrisbra/vim-xml-ftplugin/issues/1
16" 20180724 - Correctly indent xml comments https://github.com/vim/vim/issues/3200
17"
18" Notes:
19"   1) does not indent pure non-xml code (e.g. embedded scripts)
20"       2) will be confused by unbalanced tags in comments
21"       or CDATA sections.
22"       2009-05-26 patch by Nikolai Weibull
23" TODO:     implement pre-like tags, see xml_indent_open / xml_indent_close
24
25" Only load this indent file when no other was loaded.
26if exists("b:did_indent")
27    finish
28endif
29let b:did_indent = 1
30let s:keepcpo= &cpo
31set cpo&vim
32
33" [-- local settings (must come before aborting the script) --]
34" Attention: Parameter use_syntax_check is used by the docbk.vim indent script
35setlocal indentexpr=XmlIndentGet(v:lnum,1)
36setlocal indentkeys=o,O,*<Return>,<>>,<<>,/,{,},!^F
37" autoindent: used when the indentexpr returns -1
38setlocal autoindent
39
40if !exists('b:xml_indent_open')
41    let b:xml_indent_open = '.\{-}<[:A-Z_a-z]'
42    " pre tag, e.g. <address>
43    " let b:xml_indent_open = '.\{-}<[/]\@!\(address\)\@!'
44endif
45
46if !exists('b:xml_indent_close')
47    let b:xml_indent_close = '.\{-}</'
48    " end pre tag, e.g. </address>
49    " let b:xml_indent_close = '.\{-}</\(address\)\@!'
50endif
51
52let &cpo = s:keepcpo
53unlet s:keepcpo
54
55" [-- finish, if the function already exists --]
56if exists('*XmlIndentGet')
57    finish
58endif
59
60let s:keepcpo= &cpo
61set cpo&vim
62
63fun! <SID>XmlIndentWithPattern(line, pat)
64    let s = substitute('x'.a:line, a:pat, "\1", 'g')
65    return strlen(substitute(s, "[^\1].*$", '', ''))
66endfun
67
68" [-- check if it's xml --]
69fun! <SID>XmlIndentSynCheck(lnum)
70    if &syntax != ''
71        let syn1 = synIDattr(synID(a:lnum, 1, 1), 'name')
72        let syn2 = synIDattr(synID(a:lnum, strlen(getline(a:lnum)) - 1, 1), 'name')
73        if syn1 != '' && syn1 !~ 'xml' && syn2 != '' && syn2 !~ 'xml'
74            " don't indent pure non-xml code
75            return 0
76        endif
77    endif
78    return 1
79endfun
80
81" [-- return the sum of indents of a:lnum --]
82fun! <SID>XmlIndentSum(line, style, add)
83    if <SID>IsXMLContinuation(a:line) && a:style == 0
84        " no complete tag, add one additional indent level
85        " but only for the current line
86        return a:add + shiftwidth()
87    elseif <SID>HasNoTagEnd(a:line)
88        " no complete tag, return initial indent
89        return a:add
90    endif
91    if a:style == match(a:line, '^\s*</')
92        return (shiftwidth() *
93        \  (<SID>XmlIndentWithPattern(a:line, b:xml_indent_open)
94        \ - <SID>XmlIndentWithPattern(a:line, b:xml_indent_close)
95        \ - <SID>XmlIndentWithPattern(a:line, '.\{-}/>'))) + a:add
96    else
97        return a:add
98    endif
99endfun
100
101" Main indent function
102fun! XmlIndentGet(lnum, use_syntax_check)
103    " Find a non-empty line above the current line.
104    if prevnonblank(a:lnum - 1) == 0
105        " Hit the start of the file, use zero indent.
106        return 0
107    endif
108    " Find previous line with a tag (regardless whether open or closed,
109    " but always restrict the match to a line before the current one
110    " Note: xml declaration: <?xml version="1.0"?>
111    "       won't be found, as it is not a legal tag name
112    let ptag_pattern = '\%(.\{-}<[/:A-Z_a-z]\)'. '\%(\&\%<'. a:lnum .'l\)'
113    let ptag = search(ptag_pattern, 'bnW')
114    " no previous tag
115    if ptag == 0
116        return 0
117    endif
118
119    let pline = getline(ptag)
120    let pind  = indent(ptag)
121
122    let syn_name_start = '' " Syntax element at start of line (excluding whitespace)
123    let syn_name_end = ''   " Syntax element at end of line
124    let curline = getline(a:lnum)
125    if a:use_syntax_check
126        let check_lnum = <SID>XmlIndentSynCheck(ptag)
127        let check_alnum = <SID>XmlIndentSynCheck(a:lnum)
128        if check_lnum == 0 || check_alnum == 0
129            return indent(a:lnum)
130        endif
131        let syn_name_end   = synIDattr(synID(a:lnum, strlen(curline) - 1, 1), 'name')
132        let syn_name_start = synIDattr(synID(a:lnum, match(curline, '\S') + 1, 1), 'name')
133    endif
134
135    if syn_name_end =~ 'Comment' && syn_name_start =~ 'Comment'
136        return <SID>XmlIndentComment(a:lnum)
137    elseif empty(syn_name_start) && empty(syn_name_end)
138        " non-xml tag content: use indent from 'autoindent'
139        return pind + shiftwidth()
140    endif
141
142    " Get indent from previous tag line
143    let ind = <SID>XmlIndentSum(pline, -1, pind)
144    " Determine indent from current line
145    let ind = <SID>XmlIndentSum(curline, 0, ind)
146    return ind
147endfun
148
149func! <SID>IsXMLContinuation(line)
150    " Checks, whether or not the line matches a start-of-tag
151    return a:line !~ '^\s*<'
152endfunc
153
154func! <SID>HasNoTagEnd(line)
155    " Checks whether or not the line matches '>' (so finishes a tag)
156    return a:line !~ '>\s*$'
157endfunc
158
159" return indent for a commented line,
160" the middle part might be indented one additional level
161func! <SID>XmlIndentComment(lnum)
162    let ptagopen = search(b:xml_indent_open, 'bnW')
163    let ptagclose = search(b:xml_indent_close, 'bnW')
164    if getline(a:lnum) =~ '<!--'
165        " if previous tag was a closing tag, do not add
166        " one additional level of indent
167        if ptagclose > ptagopen && a:lnum > ptagclose
168            return indent(ptagclose)
169        else
170            " start of comment, add one indentation level
171            return indent(ptagopen) + shiftwidth()
172        endif
173    elseif getline(a:lnum) =~ '-->'
174        " end of comment, same as start of comment
175        return indent(search('<!--', 'bnW'))
176    else
177        " middle part of comment, add one additional level
178        return indent(search('<!--', 'bnW')) + shiftwidth()
179    endif
180endfunc
181
182let &cpo = s:keepcpo
183unlet s:keepcpo
184
185" vim:ts=4 et sts=-1 sw=0
186