interfaces: move peer `capabilities()` to the `ipeercapabilities` interface I'm not sure why this was on the `ipeercommands` interface. It appears to be because these interfaces started out as `_basewirecommands` to hold wire commands, back in 558f5b2ee10e. The capabilities interface wasn't split out until 98861a2298b5, when it pulled the capability related methods off of the `ipeerbase` interface. Perhaps it was an oversight to not look at the commands interface because, while this is a wire command, both `sshpeer` and `httppeer` now perform a handshake while instantiating the peer object, and cache a fixed list of capabilities in that object. Likewise, `localpeer` is given a fixed set of capabilities when instantiated. Back in 558f5b2ee10e, `httppeer` looks like it issued a wire command when this method was called, but `sshpeer` obtained and cached the capabilities when instantiated, and this method always returned a fixed value. There's a perfectly good interface with other capability related methods, and having it here makes it easier to implement the base `peer` mixin class.

--- a/mercurial/httppeer.py	Mon Dec 16 02:10:46 2024 -0500
+++ b/mercurial/httppeer.py	Mon Dec 16 02:41:24 2024 -0500
@@ -437,11 +437,13 @@
 
     # End of ipeerconnection interface.
 
-    # Begin of ipeercommands interface.
+    # Begin of ipeercapabilities interface.
 
     def capabilities(self):
         return self._caps
 
+    # End of ipeercapabilities interface.
+
     def _finish_inline_clone_bundle(self, stream):
         # HTTP streams must hit the end to process the last empty
         # chunk of Chunked-Encoding so the connection can be reused.
@@ -449,8 +451,6 @@
         if chunk:
             self._abort(error.ResponseError(_(b"unexpected response:"), chunk))
 
-    # End of ipeercommands interface.
-
     def _callstream(self, cmd, _compressible=False, **args):
         args = pycompat.byteskwargs(args)