testing: allow Hypothesis to enable extensions This adds support for testing extensions, including both tests that extensions don't change behaviour and test for specific commands. We use the precondition system to determine what commands are available to us. If we never use any commands enabled by an extension then that extension is *skippable* and should not have changed the behaviour of the test. We thus rerun the test with an environment variable which is designed to turn off the extension.

testing: test multiple repositories with Hypothesis This expands the Hypothesis based stateful testing so that rather than having a single repository under test, Hypothesis manages a family of repositories. Some of these are freshly created, some are clones of others.

testing: expand Hypothesis tests with branch commands This builds on the previous work to add Hypothesis based stateful testing to add branching commands to the model.

testing: generate tests operations using Hypothesis The idea of this patch is to expand the use of Hypothesis within Mercurial to use its concept of "stateful testing". The result is a test which runs a sequence of operations against a Mercurial repository. Each operation is given a set of allowed ways it can fail. Any other non-zero exit code is a test failure. At the end, the whole sequence is then reverified by generating a .t test and testing it again in pure mode (this is also useful for catching non-determinism bugs). This has proven reasonably effective at finding bugs, and has identified two problems in the shelve extension already (issue5113 and issue5112).

i18n-ja: synchronized with cb6a952efbf4

log: fix order of revisions filtered by multiple OR options (issue5100) This is the simplest workaround for the issue of the ordering of revset, which is that the expression "x or y" takes over the ordering specified by the input set (or the left-hand-side expression.) For example, the following expression A & (x | y) will be evaluated as if (A & x) | (A & y) That's wrong because revset has ordering. I'm going to fix this problem in the revset module, but that wouldn't fit to stable. So, this patch just works around the common log cases. Since this change might have some impact on performance, it is enabled only if the expression built from log options has ' or ' operation.