Tools/scripts/ndiff.py

   1 #! /usr/bin/env python
   2
   3 # Module ndiff version 1.7.0
   4 # Released to the public domain 08-Dec-2000,
   5 # by Tim Peters (tim.one@home.com).
   6
   7 # Provided as-is; use at your own risk; no warranty; no promises; enjoy!
   8
   9 # ndiff.py is now simply a front-end to the difflib.ndiff() function.
  10 # Originally, it contained the difflib.SequenceMatcher class as well.
  11 # This completes the raiding of reusable code from this formerly
  12 # self-contained script.
  13
  14 """ndiff [-q] file1 file2
  15     or
  16 ndiff (-r1 | -r2) < ndiff_output > file1_or_file2
  17
  18 Print a human-friendly file difference report to stdout.  Both inter-
  19 and intra-line differences are noted.  In the second form, recreate file1
  20 (-r1) or file2 (-r2) on stdout, from an ndiff report on stdin.
  21
  22 In the first form, if -q ("quiet") is not specified, the first two lines
  23 of output are
  24
  25 -: file1
  26 +: file2
  27
  28 Each remaining line begins with a two-letter code:
  29
  30     "- "    line unique to file1
  31     "+ "    line unique to file2
  32     "  "    line common to both files
  33     "? "    line not present in either input file
  34
  35 Lines beginning with "? " attempt to guide the eye to intraline
  36 differences, and were not present in either input file.  These lines can be
  37 confusing if the source files contain tab characters.
  38
  39 The first file can be recovered by retaining only lines that begin with
  40 "  " or "- ", and deleting those 2-character prefixes; use ndiff with -r1.
  41
  42 The second file can be recovered similarly, but by retaining only "  " and
  43 "+ " lines; use ndiff with -r2; or, on Unix, the second file can be
  44 recovered by piping the output through
  45
  46     sed -n '/^[+ ] /s/^..//p'
  47 """
  48
  49 __version__ = 1, 7, 0
  50
  51 import difflib, sys
  52
  53 def fail(msg):
  54     out = sys.stderr.write
  55     out(msg + "\n\n")
  56     out(__doc__)
  57     return 0
  58
  59 # open a file & return the file object; gripe and return 0 if it
  60 # couldn't be opened
  61 def fopen(fname):
  62     try:
  63         return open(fname, 'U')
  64     except IOError, detail:
  65         return fail("couldn't open " + fname + ": " + str(detail))
  66
  67 # open two files & spray the diff to stdout; return false iff a problem
  68 def fcompare(f1name, f2name):
  69     f1 = fopen(f1name)
  70     f2 = fopen(f2name)
  71     if not f1 or not f2:
  72         return 0
  73
  74     a = f1.readlines(); f1.close()
  75     b = f2.readlines(); f2.close()
  76     for line in difflib.ndiff(a, b):
  77         print line,
  78
  79     return 1
  80
  81 # crack args (sys.argv[1:] is normal) & compare;
  82 # return false iff a problem
  83
  84 def main(args):
  85     import getopt
  86     try:
  87         opts, args = getopt.getopt(args, "qr:")
  88     except getopt.error, detail:
  89         return fail(str(detail))
  90     noisy = 1
  91     qseen = rseen = 0
  92     for opt, val in opts:
  93         if opt == "-q":
  94             qseen = 1
  95             noisy = 0
  96         elif opt == "-r":
  97             rseen = 1
  98             whichfile = val
  99     if qseen and rseen:
 100         return fail("can't specify both -q and -r")
 101     if rseen:
 102         if args:
 103             return fail("no args allowed with -r option")
 104         if whichfile in ("1", "2"):
 105             restore(whichfile)
 106             return 1
 107         return fail("-r value must be 1 or 2")
 108     if len(args) != 2:
 109         return fail("need 2 filename args")
 110     f1name, f2name = args
 111     if noisy:
 112         print '-:', f1name
 113         print '+:', f2name
 114     return fcompare(f1name, f2name)
 115
 116 # read ndiff output from stdin, and print file1 (which=='1') or
 117 # file2 (which=='2') to stdout
 118
 119 def restore(which):
 120     restored = difflib.restore(sys.stdin.readlines(), which)
 121     sys.stdout.writelines(restored)
 122
 123 if __name__ == '__main__':
 124     args = sys.argv[1:]
 125     if "-profile" in args:
 126         import profile, pstats
 127         args.remove("-profile")
 128         statf = "ndiff.pro"
 129         profile.run("main(args)", statf)
 130         stats = pstats.Stats(statf)
 131         stats.strip_dirs().sort_stats('time').print_stats()
 132     else:
 133         main(args)