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

exchange: add a `buildobsmarkerpart` function We'll have to build an obsmarker part for both push and pull. So we build a function to factor out the common part.

obsolete: add a `commonversion` function This function returns the highest common version between the locally known formats and a list of remotely known formats. This is going to be useful to know what format should be used for exchange.

bundle2: add a `obsmarkersversion` function to extract supported version Right next to the function that encodes the supported versions in capabilities we add a function that decodes the versions out of capabilities. This is going to be useful to know what formats can be used for exchange.

bundle2: advertise the obsmarker part in bundle2 capabilities

bundle2: introduce a `getrepocaps` to retrieve the bundle2 caps of a repo This function lets extensions change the bundle2 capabilities of a repository.

obsmarker: move bundle2caps from the localrepo class to the bundle2 module The localrepo path was quicker, easier, more seductive. We'll soon add a function in another changeset to alter the capabilities.

obsmarker: produce a reply part for markers received through bundle2

obsmarker: record the number of new markers in the transaction This lets hooks be notified about new markers in the repository.

obssmarker: add a bundle2 record with the number of markers added

obsmarker: write a message with the number of markers added through bundle2

bundle2: add an obsmarkers part handler This part contains a binary stream of obsolescence markers. Received markers are added to the repository.

obsolete: make encodemarkers a public function We'll need access to it for bundle2.

obsolete: move _encodemarkers next to _readmarkers

obsstore: store and preserve ondisk version

obsolete: have _readmarkers return the format version readmarkers is not returning the version of the format it read from. This will let callers know about the format and allow them to preserve it.

obsolete: support for any known obsstore format when reading or writing We can now read and write any known format. The list of known formats currently has one element (0). The obsstore itself is not aware of multiple formats yet and always uses format 0.

obsolete: move _fm0encodeonemarker next to _fm0readmarkers

obsolete: rename _encodeonemarker to _fm0encodeonemarkers This function encodes markers in version 0 of the format.

obsolete: extract the part of _readmarkers specific to format version 0 If we are to introduce new formats we need to be able call different functions for different formats. Creating a function for format version 0 is the first step.

obsolete: rename all _fm to _fm0 This change is because these formats are used for version 0 of the obsstore format. This is going to be useful in the future when we introduce new versions of the format.