pager: add tests We've never had tests for pager, and I want to start experimenting with ways to clean up the implementation and make it a bit more graceful.

tests: flag Windows specific lines about background closing as optional

run-tests: defer leftover (?) cleanup until after all output is exhausted Previously, after matching a single line, any contiguous subsequent lines ending with (?) would be added to the output and removed from the expected output. This is a problem if the subsequent test output would have matched the consumed (?) line, because it kept the optional line and then added a duplicate without the (?) [1]. Instead, wait until there is nothing more to match before handling the leftovers. [1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2016-February/080197.html

test-run-tests: pad the failure test to preserve the run order Test size seems to dictate the order in which the tests are run, and the next patch will add to test-success.t.

changelog: backed out changeset 86de91c56355

changelog: backed out changeset 1778770e1982 We want to avoid leaking UTF-8 to main body of code wherever possible.