xref: /vim-8.2.3635/runtime/indent/python.vim (revision 05159a0c)
1" Vim indent file
2" Language:		Python
3" Maintainer:		Bram Moolenaar <[email protected]>
4" Original Author:	David Bustos <[email protected]>
5" Last Change:		2005 Feb 24
6
7" Only load this indent file when no other was loaded.
8if exists("b:did_indent")
9  finish
10endif
11let b:did_indent = 1
12
13" Some preliminary settings
14setlocal nolisp		" Make sure lisp indenting doesn't supersede us
15setlocal autoindent	" indentexpr isn't much help otherwise
16
17setlocal indentexpr=GetPythonIndent(v:lnum)
18setlocal indentkeys+=<:>,=elif,=except
19
20" Only define the function once.
21if exists("*GetPythonIndent")
22  finish
23endif
24
25" Come here when loading the script the first time.
26
27let s:maxoff = 50	" maximum number of lines to look backwards for ()
28
29function GetPythonIndent(lnum)
30
31  " If this line is explicitly joined: If the previous line was also joined,
32  " line it up with that one, otherwise add two 'shiftwidth'
33  if getline(a:lnum - 1) =~ '\\$'
34    if a:lnum > 1 && getline(a:lnum - 2) =~ '\\$'
35      return indent(a:lnum - 1)
36    endif
37    return indent(a:lnum - 1) + (exists("g:pyindent_continue") ? eval(g:pyindent_continue) : (&sw * 2))
38  endif
39
40  " If the start of the line is in a string don't change the indent.
41  if has('syntax_items')
42	\ && synIDattr(synID(a:lnum, 1, 1), "name") =~ "String$"
43    return -1
44  endif
45
46  " Search backwards for the previous non-empty line.
47  let plnum = prevnonblank(v:lnum - 1)
48
49  if plnum == 0
50    " This is the first non-empty line, use zero indent.
51    return 0
52  endif
53
54  " If the previous line is inside parenthesis, use the indent of the starting
55  " line.
56  " Trick: use the non-existing "dummy" variable to break out of the loop when
57  " going too far back.
58  call cursor(plnum, 1)
59  let parlnum = searchpair('(', '', ')', 'nbW',
60	  \ "line('.') < " . (plnum - s:maxoff) . " ? dummy :"
61	  \ . " synIDattr(synID(line('.'), col('.'), 1), 'name')"
62	  \ . " =~ '\\(Comment\\|String\\)$'")
63  if parlnum > 0
64    let plindent = indent(parlnum)
65    let plnumstart = parlnum
66  else
67    let plindent = indent(plnum)
68    let plnumstart = plnum
69  endif
70
71
72  " When inside parenthesis: If at the first line below the parenthesis add
73  " two 'shiftwidth', otherwise same as previous line.
74  " i = (a
75  "       + b
76  "       + c)
77  call cursor(a:lnum, 1)
78  let p = searchpair('(', '', ')', 'bW',
79	  \ "line('.') < " . (a:lnum - s:maxoff) . " ? dummy :"
80	  \ . " synIDattr(synID(line('.'), col('.'), 1), 'name')"
81	  \ . " =~ '\\(Comment\\|String\\)$'")
82  if p > 0
83    if p == plnum
84      " When the start is inside parenthesis, only indent one 'shiftwidth'.
85      let pp = searchpair('(', '', ')', 'bW',
86	  \ "line('.') < " . (a:lnum - s:maxoff) . " ? dummy :"
87	  \ . " synIDattr(synID(line('.'), col('.'), 1), 'name')"
88	  \ . " =~ '\\(Comment\\|String\\)$'")
89      if pp > 0
90	return indent(plnum) + (exists("g:pyindent_nested_paren") ? eval(g:pyindent_nested_paren) : &sw)
91      endif
92      return indent(plnum) + (exists("g:pyindent_open_paren") ? eval(g:pyindent_open_paren) : (&sw * 2))
93    endif
94    if plnumstart == p
95      return indent(plnum)
96    endif
97    return plindent
98  endif
99
100
101  " Get the line and remove a trailing comment.
102  " Use syntax highlighting attributes when possible.
103  let pline = getline(plnum)
104  let pline_len = strlen(pline)
105  if has('syntax_items')
106    " If the last character in the line is a comment, do a binary search for
107    " the start of the comment.  synID() is slow, a linear search would take
108    " too long on a long line.
109    if synIDattr(synID(plnum, pline_len, 1), "name") =~ "Comment$"
110      let min = 1
111      let max = pline_len
112      while min < max
113	let col = (min + max) / 2
114	if synIDattr(synID(plnum, col, 1), "name") =~ "Comment$"
115	  let max = col
116	else
117	  let min = col + 1
118	endif
119      endwhile
120      echomsg min
121      let pline = strpart(pline, 0, min - 1)
122      echomsg pline
123      sleep 1
124    endif
125  else
126    let col = 0
127    while col < pline_len
128      if pline[col] == '#'
129	let pline = strpart(pline, 0, col)
130	break
131      endif
132      let col = col + 1
133    endwhile
134  endif
135
136  " If the previous line ended with a colon, indent this line
137  if pline =~ ':\s*$'
138    return plindent + &sw
139  endif
140
141  " If the previous line was a stop-execution statement...
142  if getline(plnum) =~ '^\s*\(break\|continue\|raise\|return\)\>'
143    " See if the user has already dedented
144    if indent(a:lnum) > indent(plnum) - &sw
145      " If not, recommend one dedent
146      return indent(plnum) - &sw
147    endif
148    " Otherwise, trust the user
149    return -1
150  endif
151
152  " If the current line begins with a keyword that lines up with "try"
153  if getline(a:lnum) =~ '^\s*\(except\|finally\)\>'
154    let lnum = a:lnum - 1
155    while lnum >= 1
156      echomsg 'got here'
157      if getline(lnum) =~ '^\s*\(try\|except\)\>'
158	let ind = indent(lnum)
159	echomsg 'got here, indent is ' . ind
160	if ind >= indent(a:lnum)
161	  return -1	" indent is already less than this
162	endif
163	return ind	" line up with previous try or except
164      endif
165      let lnum = lnum - 1
166    endwhile
167    echomsg 'got to the end'
168    return -1		" no matching "try"!
169  endif
170
171  " If the current line begins with a header keyword, dedent
172  if getline(a:lnum) =~ '^\s*\(elif\|else\)\>'
173
174    " Unless the previous line was a one-liner
175    if getline(plnumstart) =~ '^\s*\(for\|if\|try\)\>'
176      return plindent
177    endif
178
179    " Or the user has already dedented
180    if indent(a:lnum) <= plindent - &sw
181      return -1
182    endif
183
184    return plindent - &sw
185  endif
186
187  " When after a () construct we probably want to go back to the start line.
188  " a = (b
189  "       + c)
190  " here
191  if parlnum > 0
192    return plindent
193  endif
194
195  return -1
196
197endfunction
198
199" vim:sw=2
200