tests/test-merge-combination-exec-bytes.t

narrow: allow merging non-conflicting change outside of the narrow spec

We use the mergestate to carry information about these merge action and
reprocess them at commit time to apply the necessary update.

The dirstate itself is never affected and remains "pure", with content only in
the narrow-spec. This file involved in such merge are therefor not listed in `hg
status`.

The current testing is based on a modification of the previous testing, that
refused to do such merges. As a result it is a bit simple and more extensive
code and testing testing will have to be introduced later. I am planning to do
this extra testing, soon.

In addition, this only works for flat manifest. Support for tree manifest will
need more work. I am not currently planning to do this work.

Differential Revision: https://phab.mercurial-scm.org/D12119

Testing recorded "modified" files for merge commit
==================================================

#require execbit

This file shows what hg says are "modified" files for a merge commit
(hg log -T {files}), somewhat exhaustively.

This test file shows merges that involves executable bit changing, check test-merge-combination-exec-bytes.t

For merges that involve files contents changing, check test-merge-combination-file-content.t

For testing of multiple corner case, check test-merge-combination-misc.t

Case with multiple or zero merge ancestors, copies/renames, and identical file contents
with different filelog revisions are not currently covered.

  $ . $TESTDIR/testlib/merge-combination-util.sh

All the merges of executable bit.

  $ range () {
  >   max=a
  >   for i in $@; do
  >     if [ $i = - ]; then continue; fi
  >     if [ $i > $max ]; then max=$i; fi
  >   done
  >   if [ $max = a ]; then echo f; else echo f x; fi
  > }
  $ isgood () { case $line in *f*x*) true;; *) false;; esac; }
  $ createfile () {
  >   if [ -f a ] && (([ -x a ] && [ $v = x ]) || (! [ -x a ] && [ $v != x ]))
  >   then touch $file
  >   else touch a; if [ $v = x ]; then chmod +x a; else chmod -x a; fi
  >   fi
  > }

  $ genmerges
  fffx  : agree on "a"
  ffxf  : agree on "a"
  ffxx  : agree on ""
  ffx-  : agree on "a"
  ff-x  : hg said "", expected "a"
  fxff  : hg said "", expected "a"
  fxfx  : hg said "a", expected ""
  fxf-  : agree on "a"
  fxxf  : agree on "a"
  fxxx  : agree on ""
  fxx-  : agree on "a"
  fx-f  : hg said "", expected "a"
  fx-x  : hg said "", expected "a"
  fx--  : hg said "", expected "a"
  f-fx  : agree on "a"
  f-xf  : agree on "a"
  f-xx  : hg said "", expected "a"
  f-x-  : agree on "a"
  f--x  : agree on "a"
  -ffx  : agree on "a"
  -fxf C: agree on "a"
  -fxx C: hg said "", expected "a"
  -fx- C: agree on "a"
  -f-x  : hg said "", expected "a"
  --fx  : agree on "a"