rust-revlog: explicit naming for `RevlogEntry` lifetime This matches what has been done in `revlog::changelog::ChangelogRevisionData`, and has the advantage of making things clearer when we introduce other, shorter lived lifetimes.

rust-changelog: introducing an intermediate `ChangelogEntry` Before this change, client code needing to extract, e.g, the Node ID and the description from a changeset had no other choice than calling both `entry_for_rev()` and `data_for_rev()`. This duplicates some (limited) computation, and more importantly imposes bad hygiene for client code: at some point of developement, the client code would have to pass over both entry and data in its internal layers, which at some point of development would raise the question whether they are consistent. We introduce the intermediate `ChangelogEntry` from which both conversion to the generic `RevlogEntry` and extraction of `ChangelogRevisionData` are possible. It might grow some convenience methods in the future. We keep the `data_for_rev()` method of `Changelog` for compatibility, pointing users at the more powerful alternative.

rust-changelog: added a test for `NULL_REVISION` special case The result is due to `Revlog.get_rev_data()` returning an empty byte string for `NULL_REVISION`, followed by special case for emtpty byte strings in `ChangelogRevisionData::new()`.

rust-changelog: made doc-comments more consistent The most important is the one about `data_for_rev`, that looked like a copy-paste leftover (got me confused first time I read this code, before I actually learned there were both `Entry` and RevisionData`. In the comment for the `struct`, "changelog" was probably more about the format in general (as documented elsewhere) than as an identifier. Some of the "Return something" had "of", half had "for".

extras: re-use Projection from jaraco.collections

extras: expose 'retained_extras' for extensions to extend

extras: extract function for projecting names from a gettable object

hgweb: add "children" into the JSON template for a changeset The children are shown in the HTML templates, so I don’t see a reason against including them in the JSON template as well.

branching: merge stable into default

help: fix formatting for http config section

branching: merge stable into default

fastexport: rework newline logic Newlines should only be added when otherwise the stream would look weird without them (on blobs), therefore they are the exception. Flip the logic so they are added, not skipped.

encoding: avoid quadratic time complexity when json-encoding non-UTF8 strings Apparently the code uses "+=" with a bytes object, which is linear-time, so the whole encoding is quadratic-time. This patch makes us use a bytearray object, instead, which has a(n amortized-)constant-time append operation. The encoding is still not particularly fast, but at least a 10MB file takes tens of seconds, not many hours to encode.

bundle: prevent implicite bundling of internal changeset Now that the two mains source of on-disk bundle are preventing the inclusion of internal changesets in their bundling. We can add a lower level check that would prevent any other leakage of internal-phase changesets. We keep the door open to some usage, like the temporary bundle using during strip for example.

bundle: abort if the user request bundling of internal changesets See inline comments for details.

strip: do now include internal changeset in the strip backup See inline comment for details.

revset: add `_internal()` predicate This predicate help core code to select internal changeset (in the internal phase).

strip: drop the assert about bundled revision This is working well, so no need for extract computation. See the previous changeset for the rationnal of still have these assert around for a short interval.

strip: explicitly compute the boundary of the backup bundle We want to make change to the set of backed up revision in a future changeset, we start with a change of the computation without any changes in the semantic to clarify later changeset. The could of costly assert are here to testify that the result is still correct. They will be removed in the next changesets, but I wanted them in this changeset to help in case someone bisect a regression to this changeset in the future.

outgoing: fix common-heads computation from `missingroots` argument When initializing a `outgoing` object, the `common set` can be defined explicitly (with the `commonheads` argument`) or implicitly (with the missingroots arguments). It turns out the logic to compute `commonheads` from `missingroots` is buggy, as it does not consider the parents of enough changesets. Previously, it only considered parents of "missingroots` items, while it need to consider all parents of missing. Here is an example: F |\ C E | | B D |/ A If we use [E] as missing-roots, the missing set is [E, F], and the common-heads are [C, D]. However you cannot only consider the parent of [E] to find them, as [C] is not a parent of [E]. This already fix the bundle generated in one test, and it would prevent many other to misbehave with future change from this series.

bundle: include required phases when saving a bundle (issue6794) We now properly computes and includes phases above secret in bundle, previously, they would be skipped, and then the code computing them would crash. Note that from this changeset, we also include the heads associated with the changegroup's "target" phase. This turned out to be necessary to ensure the movement of changeset included in the bundle, but already known locally. This explain why lines for "secret" heads appears in multiple tests.

bundle: add test bundling changeset in the "archived" phase Having this test highlight that phase bundling above secret is significantly broken. Fixes coming in the next changesets.

bundle: introduce a "v3" spec This is a small update from "v2", we use the freshly out of experimental changelog version "03' format (alignment with bundle version is a coincidence) and we now bundle phases by default. We shall use v3 as the default bundle type later, when changegroup version '03' is a bit more established

bundle: add some phase boundary in the bundle type test case Same logic as the previous one, we want the tests to cover richer cases. It actually reveal a bug in `hg bundle foo.hg REMOTE` involving secret. So this is definitly not a bad idea.

bundle: expand the graph we us for bundletype/bundlespec tests We are about to test more things, especially phase bundling, so we need a graph a bit more complex than a single node. The test "code" was a bit simplified in the process, but no test-semantic changes were made.

revset: include all non-public phases in _notpublic We forgot up to update this when new phases were added.

dirstate: remove _actual_file_name methode This is dead-code

revlog: add an exception hint when processing LFS flags without the extension It would be even better if this was either detected sooner, or the transaction completed (especially since the read/write processors aren't needed for the exchange). But this makes it easier for the user to resolve until that can be figured out.

tests: drop py36 conditionals in test-bad-extension.t Since this is a `>=` test, it's really conditionalizing py27 content, which isn't a thing anymore.

tests: drop py36 conditionals in test-hook.t Since this is a `>=` test, it's really conditionalizing py27 content, which isn't a thing anymore.

tests: drop py36 conditionals in test-http-bad-server.t Since this is a `>=` test, it's really conditionalizing py27 content, which isn't a thing anymore.

configitems: enable changegroup3 by default (unless using infinitepush) The LFS extension requires this, and if it isn't enabled on the client (or the LFS extension isn't loaded), a web client gets a 500 instead of a sensible error message. Now it gets a different (client) error, but maybe it can be handled more gracefully. c0f11347b107 indicates that treemanifest repos have this issue too. 29cfc474c5fd mentions gating this behind `experimental` so that the format could change, but that was 7 years ago and we now have an experimental `changegroup4` as well. We can keep this as a config for the next cycle in case someone runs into an unexpected problem, and then jettison it if the infinitepush bundle name changes are either acceptable as-is or can be created differently.