branchcache: stop using `copy(…)` in `replace(…)` The `copy` method is mostly used for a filter level to inherit the branchmap from a subset. So we stop using (abusing) it in "replace" to ensure `copy` is used only for inheritance purposes. Since `replace` is a method of the BranchMapCache, it seems fine to do lower level operation there.

branchcache: change the _delayed flag to an explicit `_dirty` flag This is more consistent with the logic we use for other object and it open the way to a clearer management of the cache state. Now, cache are created clean, cache update mark them dirty, writing them on disk mark them clean again.

branchcache: write branchmap in subset inheritance order This way, we can guarantee a valid subset has been written before touching the branchmap of another filter. This is especially useful as we are bout to start deleting outdated branchmap file.

branchcache: do not accept "empty update" This currently does not happens and it will be simpler that is remains that way. If all update do something, we will be able to simply declare, in a later changesets, that all update to result in a dirty branchcache.

branchcache: avoid created a `None` filter repoview when writing The repoview class is not intended to be used for unfiltered repository.

stream-clone-tests: stop filtering non existent warning This filtering was introduced in 74c004a515bc, however there is already no warning in that changeset. So I guess the warnings existed when we the patch was created but the problem was solved in another changeset that 74c004a515bc, rebased on.

stream-clone-test: simplify case testing obsolescence There is only two important things in this test: - the number of file we send, to show we picked the obsstore. - the resulting state, to show we did alter things in the process. The rest are of the number are very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol.

stream-clone-test: simplify the case testing phases There is only two important things in this test: - the number of file we send, to show we picked the phase roots. - the resulting phases, to show we did not modified them. The rest are of the number are very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol.

stream-clone-test: simplify bookmark clone The important things to test here is the number of file included (to catch that the bookmark file was sent). So we keep that part non glob'ed but glob the rest. The glob'ed numbers are very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol.

stream-clone-test: add a verify call to the "clone while changing" case It seems useful to very that the clone did not result in a corrupted copy.

stream-clone-test: add title to various test cases These case are fine as is, but as we are adding title to all the other as we simplify them, lets add title for all cases.

stream-clone-test: simplify testing of secret cloning restriction Here, we just want to check if the streaming clone is allowed and used or not. We do not care about the details of the clone itself.

stream-clone-test: simplify the background file closing test Here we just care about the fact the background file closing logic actually ran. We don't need to check the details of the cloning. The details of the output is very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol. So we filter it out.

stream-clone-test: simplify the --uncompressed alias check To check that --uncompressed is an alias we just need to check it trigger a stream clone, we don't need to check anything else.

stream-clone-test: drop an automatic pattern replacement That pattern is nice, but it prevent us to glob the number of bytes when we don't care about them. We don't care about them more often that what we currently checks so dropping this pattern will help use to simplify various tests.

stream-clone-test: simplify the test for getbundle with stream=1 The core of this tests is about checking we receive a stream bundle with such request. We don't need to look at too much of the details of the stream itself. Since the content of the stream if shifting overtime, Such check is very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol. So we reduce the size of what we check to focus on "is this a stream clone" question.

stream-clone-test: factor some piece of basic clone test out Multiple parts of this case (listing cache, checking error) are common to all cases and don't need to be in the conditionnal block. This simplify the test update.

stream-clone-test: simplify the case where server disabled it We have an option to disable it, we don't need to test it with all protocol variants. In addition there is little value in looking at the bytes to bytes details of the reply. Such check is very fragile and consume a lot of time for little value when adjusting formats, caches, and protocol.

repoview: prevent `None` to be passed as the filtername We let such instantiation slip in a previous commit, so we add an explicit check to prevent it to happen in the future.

branchcache: avoid created a `None` filter repoview when writing The repoview class is not intended to be used for unfiltered repository.

branchcache: move head writing in a `_write_headers` method Same rational: this will help having format variants.

branchcache: move head writing in a `_write_heads` method Same rational: this will help having format variants.

branchcache: move the header loading in a `_load_header` class method This will help changing header parsing in format variants.

branchcache: simplify a long line Gratuitous change to help code readability.

branchcache: rename `load` to `_load_heads` We are about to have more similar function, we rename the existing one to a more meaningful name and mark it private in the process.

branchcache: move the filename to a class attribute This prepare the introduction of more variant of cache.

test-clonebundles: simplify matching to be less flavor depends We keep the files and bytes output for the first call, but then we mostly check that we are being served a stream-clone bundle, not the actual content and size of the bundle. That aspect being tested by the stream clone test themselves.

repoview: fix changelog.__contains__ method This have been around for ten years, so we can safely that this method have few callers. However I am about to add one.