test: add a test file for relevant obsmarkers and its usage The logic around obsmarkers "relevant" to a set of revs have a couple of test around in other places but no systematic testing. In addition, all the current testing focus on the exchange case (we looks at relevant markers for '::heads'). For bundles, we'll need something a bit different. We'll no longer have set of revision going down to the repository roots. So we'll have to test these cases too. In addition, stripping obsmarkers will introduce new logic around obsmarkers that will need testing too. So a new test file make sense here. We start with a simple tests, more advanced cases are coming in the next changesets. The extra testing catch a minor bug (later in the series).

annotate: add a new experimental --skip option to skip revs This option is most useful for mechanical code modifications, especially ones that retain the same number of lines.

annotate: add core algorithm to skip a rev The core algorithm is inspired by git hyper-blame, implemented at https://chromium.googlesource.com/chromium/tools/depot_tools.git/+/master/git_hyper_blame.py. The heuristic is as documented in the comments.

annotate: make pair take all parents to pair against In upcoming patches we'll need to be aware of all parents at the same time. This also exposes a potential bug: if a line can be annotated with both parents of a merge commit, it'll always be annotated with p2, not p1. I'm not sure if that's what we want, but at least the code makes it clear now.

annotate: move pair function to top level We'll want to make this more complicated and have unit tests for it in upcoming patches.

bookmarks: fix check of hash-like name to not abort by ambiguous identifier 'mark in repo' may raise LookupError. I set it to not be warned since bookmark names shorter than 4 chars aren't checked and short names are likely to be ambiguous.

localrepo: document that __contains__() may raise LookupError

hidden: drop outdated comment about "dynamic" performance This comment is now irrelevant since we have a faster algorithm and no cache.

hidden: unify the static and dynamic blocker logic We no longer have cache and they both work the same way. Unifying the logic simplify the code and reduce the amount of set copies.

hidden: drop the hidden cache logic The improvement in time complexitty and the speed-up in computation is large enough that the has little use now. Its update time can even gets in the way. So we drop it. This will allow us to unify the static/dynamic blockers logic in the next changeset.