py3: whitelist one additional test Differential Revision: https://phab.mercurial-scm.org/D4817

logtoprocess: connect all fds to /dev/null to avoid bad interaction with pager We detected that pager is waiting for log-to-process script to finish, which is annoying when adding a script on commandfinish that does an HTTP push. There seems to be no workaround on the script side and it will make the behavior on Linux/MacOS closer to the Windows behavior. The drawback is that it makes the related tests more flaky as log-to-process outputs are now really asynchronous. If it's considered a BC change, another option would be to add a config option for this new behavior. I personally think that the different behavior between Windows and Linux is confusing and that it's a bug I would be fine with a new config option. Differential Revision: https://phab.mercurial-scm.org/D4816

logtoprocess: add a test to show pager and ltp bad interaction The next changeset will fix the bad interaction between the pager and log-to- process. Add a test first to make the next changeset easier to understand. Differential Revision: https://phab.mercurial-scm.org/D4815

py3: add one more passing test to whitelist caught by buildbot Thanks to Matt Harbison who fixed the remaining failures of this test. Differential Revision: https://phab.mercurial-scm.org/D4814

cleanupnodes: pass multiple predecessors to `createmarkers` directly

obsolete: allow multiple predecessors in createmarkers The logic for this change is similar to the change to `cleanupnodes` that we did earlier. Now that the rebase code is trying to record a fold, we need to actually record it in the markers. The first step is to have the markers creation API able to receive such fold data. To keep things sane, we restrict fold to on successors.

obsolete: preindent code in createmarkers This will help to make the next change clearer.

obsolete: explicitly pass relation items to effectflag computation To track folds, we are about to change the content of `rel`. To simplify this change, we update the `geteffectflag` function beforehand.

rebase: explicitly track collapses as fold A collapse is a large fold. It is now explicitly tracked (at the cleanupnodes API level).

rebase: use tuple as `replacement` keys Now that `cleanupnodes` support tuples as key, we update the rebase code to use them. No changes in the replacement tracked are introduced yet.