contrib/hgdiff

bdiff: normalize the diff (issue1295)

When the common part of a diff can be moved forward, move it forward.
Otherwise we don't get deterministic results (it would depends on the way we
split for the recursion).
That way we get identical hunks when doing the same change, it helps to solve
issue1295 (inconsistent diffs on different side during a merge).

#!/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, diffopts

VERSION="0.3"
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)

# 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,
                         diffopts(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)