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"""
PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
--------------------------------------------
1. This LICENSE AGREEMENT is between the Python Software Foundation
("PSF"), and the Individual or Organization ("Licensee") accessing and
otherwise using this software ("Python") in source or binary form and
its associated documentation.
2. Subject to the terms and conditions of this License Agreement, PSF
hereby grants Licensee a nonexclusive, royalty-free, world-wide
license to reproduce, analyze, test, perform and/or display publicly,
prepare derivative works, distribute, and otherwise use Python
alone or in any derivative version, provided, however, that PSF's
License Agreement and PSF's notice of copyright, i.e., "Copyright (c)
2001, 2002, 2003, 2004 Python Software Foundation; All Rights Reserved"
are retained in Python alone or in any derivative version prepared
by Licensee.
3. In the event Licensee prepares a derivative work that is based on
or incorporates Python or any part thereof, and wants to make
the derivative work available to others as provided herein, then
Licensee hereby agrees to include in any such work a brief summary of
the changes made to Python.
4. PSF is making Python available to Licensee on an "AS IS"
basis. PSF MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR
IMPLIED. BY WAY OF EXAMPLE, BUT NOT LIMITATION, PSF MAKES NO AND
DISCLAIMS ANY REPRESENTATION OR WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE OR THAT THE USE OF PYTHON WILL NOT
INFRINGE ANY THIRD PARTY RIGHTS.
5. PSF SHALL NOT BE LIABLE TO LICENSEE OR ANY OTHER USERS OF PYTHON
FOR ANY INCIDENTAL, SPECIAL, OR CONSEQUENTIAL DAMAGES OR LOSS AS
A RESULT OF MODIFYING, DISTRIBUTING, OR OTHERWISE USING PYTHON,
OR ANY DERIVATIVE THEREOF, EVEN IF ADVISED OF THE POSSIBILITY THEREOF.
6. This License Agreement will automatically terminate upon a material
breach of its terms and conditions.
7. Nothing in this License Agreement shall be deemed to create any
relationship of agency, partnership, or joint venture between PSF and
Licensee. This License Agreement does not grant permission to use PSF
trademarks or trade name in a trademark sense to endorse or promote
products or services of Licensee, or any third party.
8. By copying, installing or otherwise using Python, Licensee
agrees to be bound by the terms and conditions of this License
Agreement.
"""
#! /usr/bin/env python
# This file contains a class and a main program that perform three
# related (though complimentary) formatting operations on Python
# programs. When called as "pindent -c", it takes a valid Python
# program as input and outputs a version augmented with block-closing
# comments. When called as "pindent -d", it assumes its input is a
# Python program with block-closing comments and outputs a commentless
# version. When called as "pindent -r" it assumes its input is a
# Python program with block-closing comments but with its indentation
# messed up, and outputs a properly indented version.
# A "block-closing comment" is a comment of the form '# end <keyword>'
# where <keyword> is the keyword that opened the block. If the
# opening keyword is 'def' or 'class', the function or class name may
# be repeated in the block-closing comment as well. Here is an
# example of a program fully augmented with block-closing comments:
# def foobar(a, b):
# if a == b:
# a = a+1
# elif a < b:
# b = b-1
# if b > a: a = a-1
# # end if
# else:
# print 'oops!'
# # end if
# # end def foobar
# Note that only the last part of an if...elif...else... block needs a
# block-closing comment; the same is true for other compound
# statements (e.g. try...except). Also note that "short-form" blocks
# like the second 'if' in the example must be closed as well;
# otherwise the 'else' in the example would be ambiguous (remember
# that indentation is not significant when interpreting block-closing
# comments).
# The operations are idempotent (i.e. applied to their own output
# they yield an identical result). Running first "pindent -c" and
# then "pindent -r" on a valid Python program produces a program that
# is semantically identical to the input (though its indentation may
# be different). Running "pindent -e" on that output produces a
# program that only differs from the original in indentation.
# Other options:
# -s stepsize: set the indentation step size (default 8)
# -t tabsize : set the number of spaces a tab character is worth (default 8)
# -e : expand TABs into spaces
# file ... : input file(s) (default standard input)
# The results always go to standard output
# Caveats:
# - comments ending in a backslash will be mistaken for continued lines
# - continuations using backslash are always left unchanged
# - continuations inside parentheses are not extra indented by -r
# but must be indented for -c to work correctly (this breaks
# idempotency!)
# - continued lines inside triple-quoted strings are totally garbled
# Secret feature:
# - On input, a block may also be closed with an "end statement" --
# this is a block-closing comment without the '#' sign.
# Possible improvements:
# - check syntax based on transitions in 'next' table
# - better error reporting
# - better error recovery
# - check identifier after class/def
# The following wishes need a more complete tokenization of the source:
# - Don't get fooled by comments ending in backslash
# - reindent continuation lines indicated by backslash
# - handle continuation lines inside parentheses/braces/brackets
# - handle triple quoted strings spanning lines
# - realign comments
# - optionally do much more thorough reformatting, a la C indent
# Defaults
STEPSIZE = 8
TABSIZE = 8
EXPANDTABS = 0
import os
import re
import sys
next = {}
next['if'] = next['elif'] = 'elif', 'else', 'end'
next['while'] = next['for'] = 'else', 'end'
next['try'] = 'except', 'finally'
next['except'] = 'except', 'else', 'end'
next['else'] = next['finally'] = next['def'] = next['class'] = 'end'
next['end'] = ()
start = 'if', 'while', 'for', 'try', 'def', 'class'
class PythonIndenter:
def __init__(self, fpi = sys.stdin, fpo = sys.stdout,
indentsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
self.fpi = fpi
self.fpo = fpo
self.indentsize = indentsize
self.tabsize = tabsize
self.lineno = 0
self.expandtabs = expandtabs
self._write = fpo.write
self.kwprog = re.compile(
r'^\s*(?P<kw>[a-z]+)'
r'(\s+(?P<id>[a-zA-Z_]\w*))?'
r'[^\w]')
self.endprog = re.compile(
r'^\s*#?\s*end\s+(?P<kw>[a-z]+)'
r'(\s+(?P<id>[a-zA-Z_]\w*))?'
r'[^\w]')
self.wsprog = re.compile(r'^[ \t]*')
# end def __init__
def write(self, line):
if self.expandtabs:
self._write(line.expandtabs(self.tabsize))
else:
self._write(line)
# end if
# end def write
def readline(self):
line = self.fpi.readline()
if line: self.lineno = self.lineno + 1
# end if
return line
# end def readline
def error(self, fmt, *args):
if args: fmt = fmt % args
# end if
sys.stderr.write('Error at line %d: %s\n' % (self.lineno, fmt))
self.write('### %s ###\n' % fmt)
# end def error
def getline(self):
line = self.readline()
while line[-2:] == '\\\n':
line2 = self.readline()
if not line2: break
# end if
line = line + line2
# end while
return line
# end def getline
def putline(self, line, indent = None):
if indent is None:
self.write(line)
return
# end if
tabs, spaces = divmod(indent*self.indentsize, self.tabsize)
i = 0
m = self.wsprog.match(line)
if m: i = m.end()
# end if
self.write('\t'*tabs + ' '*spaces + line[i:])
# end def putline
def reformat(self):
stack = []
while 1:
line = self.getline()
if not line: break # EOF
# end if
m = self.endprog.match(line)
if m:
kw = 'end'
kw2 = m.group('kw')
if not stack:
self.error('unexpected end')
elif stack[-1][0] != kw2:
self.error('unmatched end')
# end if
del stack[-1:]
self.putline(line, len(stack))
continue
# end if
m = self.kwprog.match(line)
if m:
kw = m.group('kw')
if kw in start:
self.putline(line, len(stack))
stack.append((kw, kw))
continue
# end if
if next.has_key(kw) and stack:
self.putline(line, len(stack)-1)
kwa, kwb = stack[-1]
stack[-1] = kwa, kw
continue
# end if
# end if
self.putline(line, len(stack))
# end while
if stack:
self.error('unterminated keywords')
for kwa, kwb in stack:
self.write('\t%s\n' % kwa)
# end for
# end if
# end def reformat
def delete(self):
begin_counter = 0
end_counter = 0
while 1:
line = self.getline()
if not line: break # EOF
# end if
m = self.endprog.match(line)
if m:
end_counter = end_counter + 1
continue
# end if
m = self.kwprog.match(line)
if m:
kw = m.group('kw')
if kw in start:
begin_counter = begin_counter + 1
# end if
# end if
self.putline(line)
# end while
if begin_counter - end_counter < 0:
sys.stderr.write('Warning: input contained more end tags than expected\n')
elif begin_counter - end_counter > 0:
sys.stderr.write('Warning: input contained less end tags than expected\n')
# end if
# end def delete
def complete(self):
self.indentsize = 1
stack = []
todo = []
thisid = ''
current, firstkw, lastkw, topid = 0, '', '', ''
while 1:
line = self.getline()
i = 0
m = self.wsprog.match(line)
if m: i = m.end()
# end if
m = self.endprog.match(line)
if m:
thiskw = 'end'
endkw = m.group('kw')
thisid = m.group('id')
else:
m = self.kwprog.match(line)
if m:
thiskw = m.group('kw')
if not next.has_key(thiskw):
thiskw = ''
# end if
if thiskw in ('def', 'class'):
thisid = m.group('id')
else:
thisid = ''
# end if
elif line[i:i+1] in ('\n', '#'):
todo.append(line)
continue
else:
thiskw = ''
# end if
# end if
indent = len(line[:i].expandtabs(self.tabsize))
while indent < current:
if firstkw:
if topid:
s = '# end %s %s\n' % (
firstkw, topid)
else:
s = '# end %s\n' % firstkw
# end if
self.putline(s, current)
firstkw = lastkw = ''
# end if
current, firstkw, lastkw, topid = stack[-1]
del stack[-1]
# end while
if indent == current and firstkw:
if thiskw == 'end':
if endkw != firstkw:
self.error('mismatched end')
# end if
firstkw = lastkw = ''
elif not thiskw or thiskw in start:
if topid:
s = '# end %s %s\n' % (
firstkw, topid)
else:
s = '# end %s\n' % firstkw
# end if
self.putline(s, current)
firstkw = lastkw = topid = ''
# end if
# end if
if indent > current:
stack.append((current, firstkw, lastkw, topid))
if thiskw and thiskw not in start:
# error
thiskw = ''
# end if
current, firstkw, lastkw, topid = \
indent, thiskw, thiskw, thisid
# end if
if thiskw:
if thiskw in start:
firstkw = lastkw = thiskw
topid = thisid
else:
lastkw = thiskw
# end if
# end if
for l in todo: self.write(l)
# end for
todo = []
if not line: break
# end if
self.write(line)
# end while
# end def complete
# end class PythonIndenter
# Simplified user interface
# - xxx_filter(input, output): read and write file objects
# - xxx_string(s): take and return string object
# - xxx_file(filename): process file in place, return true iff changed
def complete_filter(input = sys.stdin, output = sys.stdout,
stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
pi = PythonIndenter(input, output, stepsize, tabsize, expandtabs)
pi.complete()
# end def complete_filter
def delete_filter(input= sys.stdin, output = sys.stdout,
stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
pi = PythonIndenter(input, output, stepsize, tabsize, expandtabs)
pi.delete()
# end def delete_filter
def reformat_filter(input = sys.stdin, output = sys.stdout,
stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
pi = PythonIndenter(input, output, stepsize, tabsize, expandtabs)
pi.reformat()
# end def reformat_filter
class StringReader:
def __init__(self, buf):
self.buf = buf
self.pos = 0
self.len = len(self.buf)
# end def __init__
def read(self, n = 0):
if n <= 0:
n = self.len - self.pos
else:
n = min(n, self.len - self.pos)
# end if
r = self.buf[self.pos : self.pos + n]
self.pos = self.pos + n
return r
# end def read
def readline(self):
i = self.buf.find('\n', self.pos)
return self.read(i + 1 - self.pos)
# end def readline
def readlines(self):
lines = []
line = self.readline()
while line:
lines.append(line)
line = self.readline()
# end while
return lines
# end def readlines
# seek/tell etc. are left as an exercise for the reader
# end class StringReader
class StringWriter:
def __init__(self):
self.buf = ''
# end def __init__
def write(self, s):
self.buf = self.buf + s
# end def write
def getvalue(self):
return self.buf
# end def getvalue
# end class StringWriter
def complete_string(source, stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
input = StringReader(source)
output = StringWriter()
pi = PythonIndenter(input, output, stepsize, tabsize, expandtabs)
pi.complete()
return output.getvalue()
# end def complete_string
def delete_string(source, stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
input = StringReader(source)
output = StringWriter()
pi = PythonIndenter(input, output, stepsize, tabsize, expandtabs)
pi.delete()
return output.getvalue()
# end def delete_string
def reformat_string(source, stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
input = StringReader(source)
output = StringWriter()
pi = PythonIndenter(input, output, stepsize, tabsize, expandtabs)
pi.reformat()
return output.getvalue()
# end def reformat_string
def complete_file(filename, stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
source = open(filename, 'r').read()
result = complete_string(source, stepsize, tabsize, expandtabs)
if source == result: return 0
# end if
import os
try: os.rename(filename, filename + '~')
except os.error: pass
# end try
f = open(filename, 'w')
f.write(result)
f.close()
return 1
# end def complete_file
def delete_file(filename, stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
source = open(filename, 'r').read()
result = delete_string(source, stepsize, tabsize, expandtabs)
if source == result: return 0
# end if
import os
try: os.rename(filename, filename + '~')
except os.error: pass
# end try
f = open(filename, 'w')
f.write(result)
f.close()
return 1
# end def delete_file
def reformat_file(filename, stepsize = STEPSIZE, tabsize = TABSIZE, expandtabs = EXPANDTABS):
source = open(filename, 'r').read()
result = reformat_string(source, stepsize, tabsize, expandtabs)
if source == result: return 0
# end if
import os
try: os.rename(filename, filename + '~')
except os.error: pass
# end try
f = open(filename, 'w')
f.write(result)
f.close()
return 1
# end def reformat_file
# Test program when called as a script
usage = """
usage: pindent (-c|-d|-r) [-s stepsize] [-t tabsize] [-e] [file] ...
-c : complete a correctly indented program (add #end directives)
-d : delete #end directives
-r : reformat a completed program (use #end directives)
-s stepsize: indentation step (default %(STEPSIZE)d)
-t tabsize : the worth in spaces of a tab (default %(TABSIZE)d)
-e : expand TABs into spaces (defailt OFF)
[file] ... : files are changed in place, with backups in file~
If no files are specified or a single - is given,
the program acts as a filter (reads stdin, writes stdout).
""" % vars()
def error_both(op1, op2):
sys.stderr.write('Error: You can not specify both '+op1+' and -'+op2[0]+' at the same time\n')
sys.stderr.write(usage)
sys.exit(2)
# end def error_both
def test():
import getopt
try:
opts, args = getopt.getopt(sys.argv[1:], 'cdrs:t:e')
except getopt.error, msg:
sys.stderr.write('Error: %s\n' % msg)
sys.stderr.write(usage)
sys.exit(2)
# end try
action = None
stepsize = STEPSIZE
tabsize = TABSIZE
expandtabs = EXPANDTABS
for o, a in opts:
if o == '-c':
if action: error_both(o, action)
# end if
action = 'complete'
elif o == '-d':
if action: error_both(o, action)
# end if
action = 'delete'
elif o == '-r':
if action: error_both(o, action)
# end if
action = 'reformat'
elif o == '-s':
stepsize = int(a)
elif o == '-t':
tabsize = int(a)
elif o == '-e':
expandtabs = 1
# end if
# end for
if not action:
sys.stderr.write(
'You must specify -c(omplete), -d(elete) or -r(eformat)\n')
sys.stderr.write(usage)
sys.exit(2)
# end if
if not args or args == ['-']:
action = eval(action + '_filter')
action(sys.stdin, sys.stdout, stepsize, tabsize, expandtabs)
else:
action = eval(action + '_file')
for filename in args:
action(filename, stepsize, tabsize, expandtabs)
# end for
# end if
# end def test
if __name__ == '__main__':
test()
# end if
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