tests/test-issue522

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).

#!/bin/sh

# In the merge below, the file "foo" has the same contents in both
# parents, but if we look at the file-level history, we'll notice that
# the version in p1 is an ancestor of the version in p2.  This test
# makes sure that we'll use the version from p2 in the manifest of the
# merge revision.

hg init repo
cd repo

echo foo > foo
hg ci -d '0 0' -qAm 'add foo'

echo bar >> foo
hg ci -d '0 0' -m 'change foo'

hg backout -d '0 0' -r tip -m 'backout changed foo'

hg up -C 0
touch bar
hg ci -d '0 0' -qAm 'add bar'

hg merge --debug
hg debugstate | grep foo
hg st -A foo
hg ci -d '0 0' -m 'merge'

hg manifest --debug | grep foo
hg debugindex .hg/store/data/foo.i