Add better python indenting

indent/python.vim

@@ -0,0 +1,196 @@
+" Python indent file
+" Language:	    Python
+" Maintainer:	    Eric Mc Sween <em@tomcom.de>
+" Original Author:  David Bustos <bustos@caltech.edu> 
+" Last Change:      2004 Jun 07
+
+" Only load this indent file when no other was loaded.
+if exists("b:did_indent")
+    finish
+endif
+let b:did_indent = 1
+
+setlocal expandtab
+setlocal nolisp
+setlocal autoindent
+setlocal indentexpr=GetPythonIndent(v:lnum)
+setlocal indentkeys=!^F,o,O,<:>,0),0],0},=elif,=except
+
+let s:maxoff = 50
+
+" Find backwards the closest open parenthesis/bracket/brace.
+function! s:SearchParensPair()
+    let line = line('.')
+    let col = col('.')
+    
+    " Skip strings and comments and don't look too far
+    let skip = "line('.') < " . (line - s:maxoff) . " ? dummy :" .
+                \ 'synIDattr(synID(line("."), col("."), 0), "name") =~? ' .
+                \ '"string\\|comment"'
+
+    " Search for parentheses
+    call cursor(line, col)
+    let parlnum = searchpair('(', '', ')', 'bW', skip)
+    let parcol = col('.')
+
+    " Search for brackets
+    call cursor(line, col)
+    let par2lnum = searchpair('\[', '', '\]', 'bW', skip)
+    let par2col = col('.')
+
+    " Search for braces
+    call cursor(line, col)
+    let par3lnum = searchpair('{', '', '}', 'bW', skip)
+    let par3col = col('.')
+
+    " Get the closest match
+    if par2lnum > parlnum || (par2lnum == parlnum && par2col > parcol)
+        let parlnum = par2lnum
+        let parcol = par2col
+    endif
+    if par3lnum > parlnum || (par3lnum == parlnum && par3col > parcol)
+        let parlnum = par3lnum
+        let parcol = par3col
+    endif 
+
+    " Put the cursor on the match
+    if parlnum > 0
+        call cursor(parlnum, parcol)
+    endif
+    return parlnum
+endfunction
+
+" Find the start of a multi-line statement
+function! s:StatementStart(lnum)
+    let lnum = a:lnum
+    while 1
+        if getline(lnum - 1) =~ '\\$'
+            let lnum = lnum - 1
+        else
+            call cursor(lnum, 1)
+            let maybe_lnum = s:SearchParensPair()
+            if maybe_lnum < 1
+                return lnum
+            else
+                let lnum = maybe_lnum
+            endif
+        endif
+    endwhile
+endfunction
+
+" Find the block starter that matches the current line
+function! s:BlockStarter(lnum, block_start_re)
+    let lnum = a:lnum
+    let maxindent = 10000       " whatever
+    while lnum > 1
+        let lnum = prevnonblank(lnum - 1)
+        if indent(lnum) < maxindent
+            if getline(lnum) =~ a:block_start_re
+                return lnum
+            else 
+                let maxindent = indent(lnum)
+                " It's not worth going further if we reached the top level
+                if maxindent == 0
+                    return -1
+                endif
+            endif
+        endif
+    endwhile
+    return -1
+endfunction
+                
+function! GetPythonIndent(lnum)
+
+    " First line has indent 0
+    if a:lnum == 1
+        return 0
+    endif
+    
+    " If we can find an open parenthesis/bracket/brace, line up with it.
+    call cursor(a:lnum, 1)
+    let parlnum = s:SearchParensPair()
+    if parlnum > 0
+        let parcol = col('.')
+        let closing_paren = match(getline(a:lnum), '^\s*[])}]') != -1
+        if match(getline(parlnum), '[([{]\s*$', parcol - 1) != -1
+            if closing_paren
+                return indent(parlnum)
+            else
+                return indent(parlnum) + &shiftwidth
+            endif
+        else
+            if closing_paren
+                return parcol - 1
+            else
+                return parcol
+            endif
+        endif
+    endif
+    
+    " Examine this line
+    let thisline = getline(a:lnum)
+    let thisindent = indent(a:lnum)
+
+    " If the line starts with 'elif' or 'else', line up with 'if' or 'elif'
+    if thisline =~ '^\s*\(elif\|else\)\>'
+        let bslnum = s:BlockStarter(a:lnum, '^\s*\(if\|elif\)\>')
+        if bslnum > 0
+            return indent(bslnum)
+        else
+            return -1
+        endif
+    endif
+        
+    " If the line starts with 'except' or 'finally', line up with 'try'
+    " or 'except'
+    if thisline =~ '^\s*\(except\|finally\)\>'
+        let bslnum = s:BlockStarter(a:lnum, '^\s*\(try\|except\)\>')
+        if bslnum > 0
+            return indent(bslnum)
+        else
+            return -1
+        endif
+    endif
+    
+    " Examine previous line
+    let plnum = a:lnum - 1
+    let pline = getline(plnum)
+    let sslnum = s:StatementStart(plnum)
+    
+    " If the previous line is blank, keep the same indentation
+    if pline =~ '^\s*$'
+        return -1
+    endif
+    
+    " If this line is explicitly joined, try to find an indentation that looks
+    " good. 
+    if pline =~ '\\$'
+        let compound_statement = '^\s*\(if\|while\|for\s.*\sin\|except\)\s*'
+        let maybe_indent = matchend(getline(sslnum), compound_statement)
+        if maybe_indent != -1
+            return maybe_indent
+        else
+            return indent(sslnum) + &sw * 2
+        endif
+    endif
+    
+    " If the previous line ended with a colon, indent relative to
+    " statement start.
+    if pline =~ ':\s*$'
+        return indent(sslnum) + &sw
+    endif
+
+    " If the previous line was a stop-execution statement or a pass
+    if getline(sslnum) =~ '^\s*\(break\|continue\|raise\|return\|pass\)\>'
+        " See if the user has already dedented
+        if indent(a:lnum) > indent(sslnum) - &sw
+            " If not, recommend one dedent
+            return indent(sslnum) - &sw
+        endif
+        " Otherwise, trust the user
+        return -1
+    endif
+
+    " In all other cases, line up with the start of the previous statement.
+    return indent(sslnum)
+endfunction