tests/README

exchangev2: recognize narrow patterns when pulling

pulloperation instances were recently taught to record file
include and exclude patterns to facilitate narrow file transfer.
Teaching the exchangev2 code to transfer a subset of files is
as simple as constructing a narrow matcher from these patterns and
filtering all seen file paths through it.

Keep in mind that this change only influences file data: we're
still fetching all changeset and manifest data. So, there's still
a ton of "partial clone" to implement in exchangev2.

On a personal note, I derive gratification that this feature requires
very few lines of new code to implement.

To test this, we implemented a minimal extension which allows us to specify
--include/--exclude to clone. While the narrow extension provides these
arguments, I explicitly wanted to test this functionality without the
narrow extension enabled, as that extension monkeypatches various things
and I want to isolate the behavior of core Mercurial.

Differential Revision: https://phab.mercurial-scm.org/D5132

To run the tests, do:

cd tests/
python run-tests.py

See https://mercurial-scm.org/wiki/WritingTests for
more information on writing tests.