Re: Merging bug (wrong conflicts)

[Karl Tomlinson]

Karl Tomlinson wrote:
> 
> Karl Tomlinson wrote:
> >
> > 2&3)
> >
> > Both depend on a difference between files that can be represented
> > by more than one minimal hunk.
> >
> > An example is
> >
> > Difference A:
> >
> >  1  2
> >
> >  x  y
> >  m  m
> >  x  y
> >     m
> >     y
> >
> > Does the m in file 1 match the first or second m in file 2?
> >
> > The logic in diag and compareseq is not consistent in analyze.c.
> > The match selected depends on where in the file this difference occurs
> > and on the surrounding differences.
> >
> 
> It seems more complicated than I thought.  I haven't been able to
> come up with any examples based on differences such as this or
> variations.

I finally had some success with

Difference B:

1  2

s  s
x  m1
m1 m2
m2 s
m1
x
m2
s

diff can produce hunks with either the first or second 
m1 and m2 in file 1 matching in file 2.

File 2 must be the common file to produce conflicts.

So I recommend as a test example for configuration 2) of
http://www.mail-archive.com/bug-cvs%40gnu.org/msg00803.html

M:
v
s
x
m1
m2
m1
x
m2
s
v
s
m1
x
m2
m1
m2
x
s
v

O:
s
x
m1
m2
m1
x
m2
s
v
s
x
m1
x
m2
m1
m2
x
s

Y:
s
m1
m2
s
v
s
m1
m2
s

I tested this with diffutils diff3 version 2.7 and it produced conflicts.
No conflicts with older as the common file.

The prepatch cvs analyze.c is slightly different to diffutils (in 
shift_boundaries).
I haven't tried it but suspect that the conflicts will most likely still occur.