merge with future 6.0.0

merge with default We are getting close to cutting a 6.0.0

readme: mention the fix for issue4354

checkheads: add a small debug message in case were we give up fast When node is unknown we assume it will stay. Yet, we might have markers to it that are going to be pushed. However, we do not have branch (ancestors) information unless we are very lucky an all of them are pruned. So for now we do not do anything assuming this will be rare. We still add a small debug message to help detecting such situation in the future.

checkheahds: switch algorithm to use pushed markers instead We now checks if markers involved in the push are relevant to nodes in the branch we try to replace. The approach is simpler and more robust. A test showing the limitation of the previous approach is added.

checkheads: add test where the rewrite of the other branch is not direct This will help testing that our logic is properly transitive.

check-heads: add tests about old heads indirectly pruned

checkheads: add more complexe case where a branch is split on multiple ones We extend case A-6 and A-7 with partial counterpart. These case are interesting because some of the partial pushing will (rightfully) works and some other won't.

checkheads: add a test of partially pushing a branch spread on multiple other If a branch is fully obsolete but is result are spread on multiple branch, pushing only one of them should detect we create new branches.

checkheads-tests: add missing parents recording for prune markers It is a bit too easy to forget about theses :/ If they are missing, the markers are not going to be exchanged on push.

checkheads: add some extra tests about "partial push" This adds a couple of test that checks that the head replacement code is properly ignored replacement not relevant to the push.

checkheads: handle partial obsolescence We now properly detects situations were only parts of the remote branch is obsoleted. To do so, we process children in the branch recursively to see if they will be obsolete. The current code has some trouble when the remote branch in unknown locally, or when the prune happened on a successors that is not relevant to the push. These case will be handled later. The processing code is becoming more and more complex, a lighter approach would be to check for the obsolescence markers that are relevant to the pushed set, but I prefer to stick with the current approach until more test cases are written.

test: force a push in inhibit's test Our checkheads detection code is becoming better and will prevent that push. As we do not care about this for inhibit, we simply force the push.

checkheads: basic handling of pruned heads (and associated tests) We now detect that heads was pruned and stop warning about it. Note that this has the same shortcoming as the existing code and only looks at the heads.

checkheads: give up on processing locally unknown changeset There are too many issue with locally unknown changesets, we ignore them for now while we get the core feature of the detection working.

checkheads: import our own copy of the checkheads code I expect enough change and experimental will be made that is it worthwhile having them done in evolution close to the rest of the exchange tests make sense.

compat: work around some filecache bug in 3.8 We are still compatible with this version.

obshashrange: have an half descent wireprotocol command The previous implementation was extremely hacky. The new version is based on the other discovery function and work!

obshashrange: improve message issued during discovery This is a minor new message that help to understand what is going on.

obshashrange: introduce basic sqlite caching Same as for stablerange, this is far from perfect but already a win. The cache is currently extremely volatile, but that will still be a win when doing multiple consecutive request during discovery. Better cache invalidation will happens "in the future".

stablerange: warm cache before using it server side We make sure the cache is fully up to date before starting to use it. Updating all value is more efficient and this give us a single point where we update and write on disk. Hopefully the cache have been kept up to date as we go anyway.

stablerange: warm cache before using it in findrangemissing We make sure the cache is fully up to date before starting to use it. Updating all value is more efficient and this give us a single point where we update and write on disk. Hopefully the cache have been kept up to date as we go anyway.

stablerange: warm cache on transaction (if obshashrange is enabled) If we plan to use it (obshashrange is enabled) we better keep it up to date. If a transaction adds node, we update the cache (this should also update the on disk version).

stablerange: introduce ondisk caching through sqlite There is many short cut and limitation with this first version of a cache but this allow use to envision some actual usage of the stablerange thingy so let us got for it.