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, 'r')
  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
  77     diff = difflib.ndiff(a, b)
  78     sys.stdout.writelines(diff)
  79
  80     return 1
  81
  82 # crack args (sys.argv[1:] is normal) & compare;
  83 # return false iff a problem
  84
  85 def main(args):
  86     import getopt
  87     try:
  88         opts, args = getopt.getopt(args, "qr:")
  89     except getopt.error, detail:
  90         return fail(str(detail))
  91     noisy = 1
  92     qseen = rseen = 0
  93     for opt, val in opts:
  94         if opt == "-q":
  95             qseen = 1
  96             noisy = 0
  97         elif opt == "-r":
  98             rseen = 1
  99             whichfile = val
 100     if qseen and rseen:
 101         return fail("can't specify both -q and -r")
 102     if rseen:
 103         if args:
 104             return fail("no args allowed with -r option")
 105         if whichfile in "12":
 106             restore(whichfile)
 107             return 1
 108         return fail("-r value must be 1 or 2")
 109     if len(args) != 2:
 110         return fail("need 2 filename args")
 111     f1name, f2name = args
 112     if noisy:
 113         print '-:', f1name
 114         print '+:', f2name
 115     return fcompare(f1name, f2name)
 116
 117 # read ndiff output from stdin, and print file1 (which=='1') or
 118 # file2 (which=='2') to stdout
 119
 120 def restore(which):
 121     restored = difflib.restore(sys.stdin.readlines(), which)
 122     sys.stdout.writelines(restored)
 123
 124 if __name__ == '__main__':
 125     args = sys.argv[1:]
 126     if "-profile" in args:
 127         import profile, pstats
 128         args.remove("-profile")
 129         statf = "ndiff.pro"
 130         profile.run("main(args)", statf)
 131         stats = pstats.Stats(statf)
 132         stats.strip_dirs().sort_stats('time').print_stats()
 133     else:
 134         main(args)