sparse: add test showing `hg merge` is broken while using sparse extension
This patch adds a test to demonstrate that `hg merge` is broken in some cases
while using sparse extension.
The case is when you have a file which is:
* modified between current wdir parent and merge base
* deleted between merge base and merge destination
* excluded from sparse checkout
Doing `hg merge` results in file not found error. Next patch will fix this.
Differential Revision: https://phab.mercurial-scm.org/D3983
Mercurial
=========
Mercurial is a fast, easy to use, distributed revision control tool
for software developers.
Basic install::
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
Running without installing::
$ make local # build for inplace usage
$ ./hg --version # should show the latest version
See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.