Remove duplicate bunidiff code from hgdiff, importing from mdiff.py instead

contrib/hgdiff

@@ -1,224 +1,104
 #!/usr/bin/env python
 
 import os, sys, struct, stat
 import difflib
 import re
 from optparse import OptionParser
 from mercurial.bdiff import bdiff, blocks
+from mercurial.mdiff import bunidiff
 
 VERSION="0.2"
 usage = "usage: %prog [options] file1 file2"
 parser = OptionParser(usage=usage)
 
 parser.add_option("-d", "--difflib", action="store_true", default=False)
 parser.add_option('-x', '--count', default=1)
 parser.add_option('-c', '--context', type="int", default=3)
 parser.add_option('-p', '--show-c-function', action="store_true", default=False)
 parser.add_option('-w', '--ignore-all-space', action="store_true", 
                   default=False)
 
 (options, args) = parser.parse_args()
 
 if not args:
     parser.print_help()
     sys.exit(1)
 
-# somewhat self contained replacement for difflib.unified_diff
-# t1 and t2 are the text to be diffed
-# l1 and l2 are the text broken up into lines
-# header1 and header2 are the filenames for the diff output
-# context is the number of context lines
-# showfunc enables diff -p output
-# ignorews ignores all whitespace changes in the diff
-def bunidiff(t1, t2, l1, l2, header1, header2, context=3, showfunc=False, 
-             ignorews=False):
-    def contextend(l, len):
-        ret = l + context
-        if ret > len:
-            ret = len
-        return ret
-
-    def contextstart(l):
-        ret = l - context
-        if ret < 0:
-            return 0
-        return ret
-
-    def yieldhunk(hunk, header):
-        if header:
-            for x in header:
-                yield x
-        (astart, a2, bstart, b2, delta) = hunk
-        aend = contextend(a2, len(l1))
-        alen = aend - astart
-        blen = b2 - bstart + aend - a2
-
-        func = ""
-        if showfunc:
-            # walk backwards from the start of the context
-            # to find a line starting with an alphanumeric char.
-            for x in xrange(astart, -1, -1):
-                t = l1[x]
-                if funcre.match(t):
-                    func = ' ' + t[:40]
-                    break
-            
-        yield "@@ -%d,%d +%d,%d @@%s\n" % (astart + 1, alen, 
-                                           bstart + 1, blen, func)
-        for x in delta:
-            yield x
-        for x in xrange(a2, aend):
-            yield ' ' + l1[x]
-
-    header = [ "--- %s\t\n" % header1, "+++ %s\t\n" % header2 ]
-
-    if showfunc:
-        funcre = re.compile('\w')
-    if ignorews:
-        wsre = re.compile('[ \t]')
-
-    # bdiff.blocks gives us the matching sequences in the files.  The loop
-    # below finds the spaces between those matching sequences and translates
-    # them into diff output.
-    #
-    diff = blocks(t1, t2)
-    hunk = None
-    for i in xrange(len(diff)):
-        # The first match is special.
-        # we've either found a match starting at line 0 or a match later
-        # in the file.  If it starts later, old and new below will both be
-        # empty and we'll continue to the next match.
-        if i > 0:
-            s = diff[i-1]
-        else:
-            s = [0, 0, 0, 0]
-        delta = []
-        s1 = diff[i]
-        a1 = s[1]
-        a2 = s1[0]
-        b1 = s[3]
-        b2 = s1[2]
-        old = l1[a1:a2]
-        new = l2[b1:b2]
-
-        # bdiff sometimes gives huge matches past eof, this check eats them,
-        # and deals with the special first match case described above
-        if not old and not new:
-            continue
-
-        if ignorews:
-            wsold = wsre.sub('', "".join(old))
-            wsnew = wsre.sub('', "".join(new))
-            if wsold == wsnew:
-                continue
-
-        astart = contextstart(a1)
-        bstart = contextstart(b1)
-        prev = None
-        if hunk:
-            # join with the previous hunk if it falls inside the context
-            if astart < hunk[1] + context + 1:
-                prev = hunk
-                astart = hunk[1]
-                bstart = hunk[3]
-            else:
-                for x in yieldhunk(hunk, header):
-                    yield x
-                # we only want to yield the header if the files differ, and
-                # we only want to yield it once.
-                header = None
-        if prev:
-            # we've joined the previous hunk, record the new ending points.
-            hunk[1] = a2
-            hunk[3] = b2
-            delta = hunk[4]
-        else:
-            # create a new hunk
-            hunk = [ astart, a2, bstart, b2, delta ]
-
-        delta[len(delta):] = [ ' ' + x for x in l1[astart:a1] ]
-        delta[len(delta):] = [ '-' + x for x in old ]
-        delta[len(delta):] = [ '+' + x for x in new ]
-
-    if hunk:
-        for x in yieldhunk(hunk, header):
-            yield x
-
 # simple utility function to put all the
 # files from a directory tree into a dict
 def buildlist(names, top):
     tlen = len(top)
     for root, dirs, files in os.walk(top):
         l = root[tlen + 1:]
         for x in files:
             p = os.path.join(root, x)
             st = os.lstat(p)
             if stat.S_ISREG(st.st_mode):
                 names[os.path.join(l, x)] = (st.st_dev, st.st_ino)
 
 def diff_files(file1, file2):
     if file1 == None:
         b = file(file2).read().splitlines(1)
         l1 = "--- %s\n" % (file2)
         l2 = "+++ %s\n" % (file2)
         l3 = "@@ -0,0 +1,%d @@\n" % len(b)
         l = [l1, l2, l3] + ["+" + e for e in b]
     elif file2 == None:
         a = file(file1).read().splitlines(1)
         l1 = "--- %s\n" % (file1)
         l2 = "+++ %s\n" % (file1)
         l3 = "@@ -1,%d +0,0 @@\n" % len(a)
         l = [l1, l2, l3] + ["-" + e for e in a]
     else:
         t1 = file(file1).read()
         t2 = file(file2).read()
         l1 = t1.splitlines(1)
         l2 = t2.splitlines(1)
         if options.difflib:
             l = difflib.unified_diff(l1, l2, file1, file2)
         else:
             l = bunidiff(t1, t2, l1, l2, file1, file2, context=options.context,
                      showfunc=options.show_c_function,
                      ignorews=options.ignore_all_space)
     for x in l:
         if x[-1] != '\n':
             x += "\n\ No newline at end of file\n"
         print x,
 
 file1 = args[0]
 file2 = args[1]
 
 if os.path.isfile(file1) and os.path.isfile(file2):
     diff_files(file1, file2)
 elif os.path.isdir(file1):
     if not os.path.isdir(file2):
         sys.stderr.write("file types don't match\n")
         sys.exit(1)
 
     d1 = {}
     d2 = {}
 
     buildlist(d1, file1)
     buildlist(d2, file2)
     keys = d1.keys()
     keys.sort()
     for x in keys:
         if x not in d2:
             f2 = None
         else:
             f2 = os.path.join(file2, x)
             st1 = d1[x]
             st2 = d2[x]
             del d2[x]
             if st1[0] == st2[0] and st1[1] == st2[1]:
                 sys.stderr.write("%s is a hard link\n" % x)
                 continue
         x = os.path.join(file1, x)
         diff_files(x, f2)
     keys = d2.keys()
     keys.sort()
     for x in keys:
         f1 = None
         x = os.path.join(file2, x)
         diff_files(f1, x)