branchmap: issue a single call to `ancestors` for all heads There is no reason to make multiple calls. This provides a massive speedup for repo with a lot of heads. On a strongly headed repo this gives humble speedup in simple case: from 8.1097 to 5.1051 And massive speedup in other case: from 7.8787 to 0.1984

test-ancestor: add a test for `ancestor` with ancestry within the initset I was wondering if revisions in the initial set that are still ancestors of other elements in the initial set were yielded by `changelog.ancestors`. I now have my answer (they do) and Mercurial has a new test.

bundle2: pull obsmarkers relevant to the pulled set through bundle2 We use the new `obsheads` argument to retrieve them in a bundle2 part at the same time as the changegroup.

getbundle: add `obsmarkers` argument to getbundle This argument triggers the retrieval of all markers relevant to the set of changesets defined by the nodes in `heads`.

pull: use the "cg" argument when pulling a bundle2 We use the `cg` argument to disable the generation of a changegroup part. This is useful to pull information when changesets are already in sync (phases, obsmarkers).

wireprotocol: fix 'boolean' handling The encoding and decoding code were swapped. This is now fixed.

push: only push obsmarkers relevant to the "pushed subset" We should only exchange obsolete markers related to the changesets that are being exchanged. For example, if `A'` is a successor of `A`, we do not want to push the marker if we are not exchanging `A'`. Otherwise `A` would disappear without a successor, leading to confusion for both users and the evolution mechanism. Therefore we now exchange only the markers relevant to the subset of nodes involved in the push (the nodes themselves may be already common but were selected by --rev (or the lack of --rev)). Note that all selected markers are still exchanged on each push. We do not have a discovery protocol for markers in core yet. Such discovery would save us the exchange of markers known on both side.

test-obsolete: sort the output of debugobsolete The set of relevant markers is currently unordered. Therefore the markers will be added in arbitrary order. We sort the list of markers beforehand to ensure stable output for testing.

test-obsolete: change a marker so it is relevant to the exchanged set We are going to only exchange markers relevant to the exchanged changesets. So we need to change this marker to use a known changeset as a successor instead of a precursor.

push: use bundle2 to push obsmarkers when possible