checkunresolved: move to new package to help avoid import cycles This will allow localrepo to stop using cmdutil, which should avoid some future import cycles. There's room for an adventurous soul to delve deeper into merge.py and figure out how to disentangle more of it - it appears to be a nexus of cycle problems. Some of it might be able to move into this new mergeutil package.

cmdutil: mark dirstateguard as deprecated I sincerely doubt this is used in external code, as grepping the extensions I keep locally (including Facebook's hgexperimental and evolve) indicate nobody outside of core uses this. As such, I'd also welcome just dropping this name forward entirely.

localrepo: refer to dirstateguard by its new name

commands: refer to dirstateguard by its new name

rebase: refer to dirstateguard by its new name

mq: refer to dirstateguard by its new name

dirstateguard: move to new module so I can break some layering violations Recently in a review I noticed that localrepo almost has no reason to import cmdutil anymore. Also, cmdutil is a little on the enormous side, so breaking this class out strikes me as a win.

keepalive: discard legacy Python support for error handling We never changed the behavior defined by this attribute anyway, so just jettison all of this support.

mergemod: drop support for merge.update without a target This was to be deleted after 3.9.

dispatch: stop supporting non-use of @command We said we'd delete this after 3.8. It's time.

httppeer: document why super() isn't used Adding a follow-up to document lack of super() per Augie's request.

exchange: add `_getbookmarks()` function This function will be used to generate bookmarks bundle2 part. It is a separate function in order to make it easy to overwrite it in extensions. Passing `kwargs` to the function makes it easy to add new parameters in extensions.

bookmarks: use listbinbookmarks() in listbookmarks()

bookmarks: introduce listbinbookmarks() `bookmarks` bundle2 part will work with binary nodes. To avoid unnecessary conversions between binary and hex nodes let's add `listbinbookmarks()` that returns binary nodes. For now this function is a copy-paste of listbookmarks(). In the next patch this copy-paste will be removed.

ui: add configoverride context manager I feel like this idea might've been discussed before, so please feel free to point me to the right mailing list entry to read about why it should not be done. We have a common pattern of the following code: backup = ui.backupconfig(section, name) try: ui.setconfig(section, name, temporaryvalue, source) do_something() finally: ui.restoreconfig(backup) IMO, this looks better: with ui.configoverride({(section, name): temporaryvalue}, source): do_something() Especially this becomes more convenient when one has to backup multiple config values before doing something. In such case, adding a new value to backup requires codemod in three places.

archival: simplify code and drop message about Python 2.5

bugzilla: stop mentioning Pythons older than 2.6 We don't support those anyway.

tests: update sitecustomize to use uuid1() instead of randrange() The comments mention that uuid would be better, so let's go ahead and make good on an old idea.

win32mbcs: drop code that was catering to Python 2.3 and earlier

httppeer: drop an except block that says it happens only on Python 2.3

windows: do not replace sys.stdout by winstdout Now we use util.stdout everywhere.

py3: bulk replace sys.stdin/out/err by util's Almost all sys.stdin/out/err in hgext/ and mercurial/ are replaced by util's. There are a few exceptions: - lsprof.py and statprof.py are untouched since they are a kind of vendor code and they never import mercurial modules right now. - ui._readline() needs to replace sys.stdin and stdout to pass them to raw_input(). We'll need another workaround here.

py3: provide bytes stdin/out/err through util module Since standard streams are TextIO on Python 3, we can't use sys.stdin/out/err directly. Fortunately we can get the underlying BytesIO via .buffer as long as the streams aren't replaced by e.g. StringIO. stdin/out/err are provided through util so we can wrap them by platform API.

util: rewrite pycompat imports to make pyflakes always happy I'll add more imports which would confuse pyflakes.

windows: do not replace sys.__stdout__ Now we don't use sys.__stdout__ except for getting its fileno(), so we no longer have to wrap it by winstdout. This helps adding pycompat.stdin/out/err.

py3: update test-check-py3-compat.t output This part remains unchanged because it runs in Python 3 only.

py3: use pycompat.sysargv in dispatch.run() Another one to have a bytes result from sys.argv in Python 3. This one is also a part of running `hg version` on Python 3.

py3: use pycompat.sysargv in scmposix.systemrcpath() sys.argv returns unicodes on Python 3. We have pycompat.sysargv which returns bytes encoded using os.fsencode(). After this patch scmposix.systemrcpath() returns bytes in Python 3 world. This change is also a part of making `hg version` run in Python 3.

wireproto: perform chunking and compression at protocol layer (API) Currently, the "streamres" response type is populated with a generator of chunks with compression possibly already applied. This puts the onus on commands to perform chunking and compression. Architecturally, I think this is the wrong place to perform this work. I think commands should say "here is the data" and the protocol layer should take care of encoding the final bytes to put on the wire. Additionally, upcoming commits will improve wire protocol support for compression. Having a central place for performing compression in the protocol transport layer will be easier than having to deal with compression at the commands layer. This commit refactors the "streamres" response type to accept either a generator or an object with "read." Additionally, the type now accepts a flag indicating whether the response is a "version 1 compressible" response. This basically identifies all commands currently performing compression. I could have used a special type for this, but a flag works just as well. The argument name foreshadows the introduction of wire protocol changes, hence the "v1." The code for chunking and compressing has been moved to the output generation function for each protocol transport. Some code has been inlined, resulting in the deletion of now unused methods.

httppeer: use compression engine API for decompressing responses In preparation for supporting multiple compression formats on the wire protocol, we need all users of the wire protocol to use compression engine APIs. This commit ports the HTTP wire protocol client to use the compression engine API. The code for handling the HTTPException is a bit hacky. Essentially, HTTPException could be thrown by any read() from the socket. However, as part of porting the API, we no longer have a generator wrapping the socket and we don't have a single place where we can trap the exception. We solve this by introducing a proxy class that intercepts read() and converts the exception appropriately. In the future, we could introduce a new compression engine API that supports emitting a generator of decompressed chunks. This would eliminate the need for the proxy class. As I said when I introduced the decompressorreader() API, I'm not fond of it and would support transitioning to something better. This can be done as a follow-up, preferably once all the code is using the compression engine API and we have a better idea of the API needs of all the consumers.