xref: /vim-8.2.3635/runtime/indent/python.vim (revision 4399ef47)
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 08
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
25let s:maxoff = 50	" maximum number of lines to look backwards for ()
26
27function GetPythonIndent(lnum)
28  " If this line is explicitly joined: If the previous line was also joined,
29  " line it up with that one, otherwise add two 'shiftwidth'
30  if getline(a:lnum - 1) =~ '\\$'
31    if a:lnum > 1 && getline(a:lnum - 2) =~ '\\$'
32      return indent(a:lnum - 1)
33    endif
34    return indent(a:lnum - 1) + (&sw * 2)
35  endif
36
37  " If the start of the line is in a string don't change the indent.
38  if has('syntax_items')
39	\ && synIDattr(synID(a:lnum, 1, 1), "name") =~ "String$"
40    return -1
41  endif
42
43  " Search backwards for the previous non-empty line.
44  let plnum = prevnonblank(v:lnum - 1)
45
46  if plnum == 0
47    " This is the first non-empty line, use zero indent.
48    return 0
49  endif
50
51  " If the previous line is inside parenthesis, use the indent of the starting
52  " line.
53  " Trick: use the non-existing "dummy" variable to break out of the loop when
54  " going too far back.
55  call cursor(plnum, 1)
56  let parlnum = searchpair('(', '', ')', 'nbW',
57	  \ "line('.') < " . (plnum - s:maxoff) . " ? dummy :"
58	  \ . " synIDattr(synID(line('.'), col('.'), 1), 'name')"
59	  \ . " =~ '\\(Comment\\|String\\)$'")
60  if parlnum > 0
61    let plindent = indent(parlnum)
62    let plnumstart = parlnum
63  else
64    let plindent = indent(plnum)
65    let plnumstart = plnum
66  endif
67
68
69  " When inside parenthesis: If at the first line below the parenthesis add
70  " two 'shiftwidth', otherwise same as previous line.
71  " i = (a
72  "       + b
73  "       + c)
74  call cursor(a:lnum, 1)
75  let p = searchpair('(', '', ')', 'bW',
76	  \ "line('.') < " . (a:lnum - s:maxoff) . " ? dummy :"
77	  \ . " synIDattr(synID(line('.'), col('.'), 1), 'name')"
78	  \ . " =~ '\\(Comment\\|String\\)$'")
79  if p > 0
80    if p == plnum
81      " When the start is inside parenthesis, only indent one 'shiftwidth'.
82      let pp = searchpair('(', '', ')', 'bW',
83	  \ "line('.') < " . (a:lnum - s:maxoff) . " ? dummy :"
84	  \ . " synIDattr(synID(line('.'), col('.'), 1), 'name')"
85	  \ . " =~ '\\(Comment\\|String\\)$'")
86      if pp > 0
87	return indent(plnum) + &sw
88      endif
89      return indent(plnum) + (&sw * 2)
90    endif
91    if plnumstart == p
92      return indent(plnum)
93    endif
94    return plindent
95  endif
96
97
98  " Get the line and remove a trailing comment.
99  " Use syntax highlighting attributes when possible.
100  let pline = getline(plnum)
101  let pline_len = strlen(pline)
102  if has('syntax_items')
103    " If the last character in the line is a comment, do a binary search for
104    " the start of the comment.  synID() is slow, a linear search would take
105    " too long on a long line.
106    if synIDattr(synID(plnum, pline_len, 1), "name") =~ "Comment$"
107      let min = 1
108      let max = pline_len
109      while min < max
110	let col = (min + max) / 2
111	if synIDattr(synID(plnum, col, 1), "name") =~ "Comment$"
112	  let max = col
113	else
114	  let min = col + 1
115	endif
116      endwhile
117      echomsg min
118      let pline = strpart(pline, 0, min - 1)
119      echomsg pline
120      sleep 1
121    endif
122  else
123    let col = 0
124    while col < pline_len
125      if pline[col] == '#'
126	let pline = strpart(pline, 0, col)
127	break
128      endif
129      let col = col + 1
130    endwhile
131  endif
132
133  " If the previous line ended with a colon, indent this line
134  if pline =~ ':\s*$'
135    return plindent + &sw
136  endif
137
138  " If the previous line was a stop-execution statement...
139  if getline(plnum) =~ '^\s*\(break\|continue\|raise\|return\)\>'
140    " See if the user has already dedented
141    if indent(a:lnum) > indent(plnum) - &sw
142      " If not, recommend one dedent
143      return indent(plnum) - &sw
144    endif
145    " Otherwise, trust the user
146    return -1
147  endif
148
149  " If the current line begins with a keyword that lines up with "try"
150  if getline(a:lnum) =~ '^\s*\(except\|finally\)\>'
151    let lnum = a:lnum - 1
152    while lnum >= 1
153      echomsg 'got here'
154      if getline(lnum) =~ '^\s*\(try\|except\)\>'
155	let ind = indent(lnum)
156	echomsg 'got here, indent is ' . ind
157	if ind >= indent(a:lnum)
158	  return -1	" indent is already less than this
159	endif
160	return ind	" line up with previous try or except
161      endif
162      let lnum = lnum - 1
163    endwhile
164    echomsg 'got to the end'
165    return -1		" no matching "try"!
166  endif
167
168  " If the current line begins with a header keyword, dedent
169  if getline(a:lnum) =~ '^\s*\(elif\|else\)\>'
170
171    " Unless the previous line was a one-liner
172    if getline(plnumstart) =~ '^\s*\(for\|if\|try\)\>'
173      return plindent
174    endif
175
176    " Or the user has already dedented
177    if indent(a:lnum) <= plindent - &sw
178      return -1
179    endif
180
181    return plindent - &sw
182  endif
183
184  " When after a () construct we probably want to go back to the start line.
185  " a = (b
186  "       + c)
187  " here
188  if parlnum > 0
189    return plindent
190  endif
191
192  return -1
193
194endfunction
195
196" vim:sw=2
197