--- /dev/null
+#! /ufs/guido/bin/sgi/python
+#! /usr/local/bin/python
+
+# This file contains a class and a main program that perform two
+# related (though complimentary) formatting operations on Python
+# programs. When called as "pindend -c", it takes a valid Python
+# program as input and outputs a version augmented with block-closing
+# comments. 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).
+
+# Both 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).
+
+# 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)
+# 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
+
+import os
+import regex
+import string
+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 = 8, tabsize = 8):
+ self.fpi = fpi
+ self.fpo = fpo
+ self.indentsize = indentsize
+ self.tabsize = tabsize
+ self.lineno = 0
+ self.write = fpo.write
+ self.kwprog = regex.symcomp(
+ '^[ \t]*\(<kw>[a-z]+\)'
+ '\([ \t]+\(<id>[a-zA-Z_][a-zA-Z0-9_]*\)\)?'
+ '[^a-zA-Z0-9_]')
+ self.endprog = regex.symcomp(
+ '^[ \t]*#?[ \t]*end[ \t]+\(<kw>[a-z]+\)'
+ '\([ \t]+\(<id>[a-zA-Z_][a-zA-Z0-9_]*\)\)?'
+ '[^a-zA-Z0-9_]')
+ self.wsprog = regex.compile('^[ \t]*')
+ # end def __init__
+
+ 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 = max(0, self.wsprog.match(line))
+ 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
+ if self.endprog.match(line) >= 0:
+ kw = 'end'
+ kw2 = self.endprog.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
+ if self.kwprog.match(line) >= 0:
+ kw = self.kwprog.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 complete(self):
+ self.indentsize = 1
+ stack = []
+ todo = []
+ current, firstkw, lastkw, topid = 0, '', '', ''
+ while 1:
+ line = self.getline()
+ i = max(0, self.wsprog.match(line))
+ if self.endprog.match(line) >= 0:
+ thiskw = 'end'
+ endkw = self.endprog.group('kw')
+ thisid = self.endprog.group('id')
+ elif self.kwprog.match(line) >= 0:
+ thiskw = self.kwprog.group('kw')
+ if not next.has_key(thiskw):
+ thiskw = ''
+ # end if
+ if thiskw in ('def', 'class'):
+ thisid = self.kwprog.group('id')
+ else:
+ thisid = ''
+ # end if
+ elif line[i:i+1] in ('\n', '#'):
+ todo.append(line)
+ continue
+ else:
+ thiskw = ''
+ # end if
+ indent = len(string.expandtabs(line[:i], 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
+
+def test():
+ import getopt
+ opts, args = getopt.getopt(sys.argv[1:], 'crs:t:')
+ action = None
+ stepsize = 8
+ tabsize = 8
+ for o, a in opts:
+ if o == '-c':
+ action = PythonIndenter.complete
+ elif o == '-r':
+ action = PythonIndenter.reformat
+ elif p == '-s':
+ stepsize = string.atoi(a)
+ elif p == '-t':
+ tabsize = string.atoi(a)
+ # end if
+ # end for
+ if not action:
+ print 'You must specify -c(omplete) or -r(eformat)'
+ sys.exit(2)
+ # end if
+ if not args: args = ['-']
+ # end if
+ for file in args:
+ if file == '-':
+ fp = sys.stdin
+ else:
+ fp = open(file, 'r')
+ # end if
+ pi = PythonIndenter(fp, sys.stdout, stepsize, tabsize)
+ action(pi)
+ if fp != sys.stdin: fp.close()
+ # end if
+ # end for
+# end def test
+
+if __name__ == '__main__':
+ test()
+# end if
projects / thirdparty / Python / cpython.git / commitdiff
