demandimport: omit default value of "level" at construction of _demandmod This makes construction of _demandmod require explicit level value, and helps to avoid issues like issue5208 in the future.

demandimport: import sub-module relatively as expected (issue5208) Before this patch, importing sub-module might (1) fail or (2) success but import incorrect module, because demandimport tries to import sub-module with level=-1 (on Python 2.x) or level=0 (on Python 3.x), which is default value of "level" argument at construction of "_demandmod" proxy object. (1) on Python 3.x, importing sub-module always fails to import existing sub-module (2) both on Python 2.x and 3.x, importing sub-module might import same name module on root level unintentionally On Python 2.x, existing sub-module is prior to this unexpected module. Therefore, this problem hasn't appeared. To import sub-module relatively as expected, this patch specifies "1" as import level explicitly at construction of "_demandmod" proxy object for sub-module.

wireproto: remove gboptslist (API) This variable has been unused since ce25f465e572, which was over 2 years ago. gboptsmap should be used instead. Marking as API because this could break extensions.

wireproto: unescape argument names in batch command (BC) Clients escape both argument names and values when using the batch command. Yet the server was only unescaping argument values. Fortunately we don't have any argument names that need escaped. But that isn't an excuse to lack symmetry in the code. Since the server wasn't properly unescaping argument names, this means we can never introduce an argument to a batchable command that needs escaped because an old server wouldn't properly decode its name. So we've introduced an assertion to detect the accidental introduction of this in the future. Of course, we could introduce a server capability that says the server knows how to decode argument names and allow special argument names to go through. But until there is a need for it (which I doubt there will be), we shouldn't bother with adding an unused capability.

wireproto: consolidate code for obtaining "cmds" argument value Both wireproto.py and sshpeer.py had code for producing the value to the "cmds" argument used by the "batch" command. This patch extracts that code to a standalone function and uses it.

revlog: use `iter(callable, sentinel)` instead of while True This is functionally equivalent, but is a little more concise.