evolve: extract the code computing dependencies in a separate function The code to compute dependencies between unstable changeset can be reused to compute the next reveset. This patch extracts it in its own function to make it reusable.

directaccess: add mechanism to load directaccess after some other extensions directaccess needs to load after some extensions to avoid interfering with them. This patch adds a mechanism to specify what extension directaccess needs to load after.

evolve: add another test for evolve --rev This patch adds one test for three conditions not covered before: - evolve --rev on a stack with obsolete commits without successors - evolve --rev on two sets of stacks in parallel - evolve --rev on a set of stack partially solvable (because all of the commits of the stack are not specified with --rev)

evolve: add a more complex test for evolve --rev The previous tests of evolve --rev would have passed with an ordering of revs by increasing revision numbers. This patch adds a test that would fail if that was what we were doing and therefore tests the implementation better.