run-tests: produce error on running a failing test This patch fixes a regression recently introduced by a refactoring (see 92a6b16c9186 and about 200 previous changesets from Gregory Szorc). It produce an error message everytime with a test filename which gets fail while testing except at one condition when '--nodiff' option is enabled.

test-run-tests.t: test running a passing test

run-tests: don't check for the mercurial library used when using --with-hg In the ``--with-hg`` case, we cannot properly infer the location of the mercurial library, so we skip the warning completely.