1  #! /usr/bin/env python3
       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)
      64      except IOError as 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, end=' ')
      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 as 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)