Feat: Adding Yamux as default multiplexer, keeping Mplex as fallback (#538)

* feat: Replace mplex with yamux as default multiplexer in py-libp2p

* Retain Mplex alongside Yamux in new_swarm with messaging that Yamux is preferred

* moved !BBHII to a constant YAMUX_HEADER_FORMAT at the top of yamux.py with a comment explaining its structure

* renamed the news fragment to 534.feature.rst and updated the description

* renamed the news fragment to 534.feature.rst and updated the description

* added a docstring to clarify that Yamux does not support deadlines natively

* Remove the __main__ block entirely from test_yamux.py

* Replaced the print statements in test_yamux.py with logging.debug

* Added a comment linking to the spec for clarity

* Raise NotImplementedError in YamuxStream.set_deadline per review

* Add muxed_conn to YamuxStream and test deadline NotImplementedError

* Fix Yamux implementation to meet libp2p spec

* Fix None handling in YamuxStream.read and Yamux.read_stream

* Fix test_connected_peers.py to correctly handle peer connections

* fix: Ensure StreamReset is raised on read after local reset in yamux

* fix: Map MuxedStreamError to StreamClosed in NetStream.write for Yamux

* fix: Raise MuxedStreamReset in Yamux.read_stream for closed streams

* fix: Correct Yamux stream read behavior for NetStream tests

Fixed 	est_net_stream_read_after_remote_closed by updating NetStream.read to raise StreamEOF when the stream is remotely closed and no data is available, aligning with test expectations and Fixed 	est_net_stream_read_until_eof by modifying YamuxStream.read to block until the stream is closed (
ecv_closed=True) for
=-1 reads, ensuring data is only returned after remote closure.

* fix: Correct Yamux stream read behavior for NetStream tests

Fixed 	est_net_stream_read_after_remote_closed by updating NetStream.read to raise StreamEOF when the stream is remotely closed and no data is available, aligning with test expectations and Fixed 	est_net_stream_read_until_eof by modifying YamuxStream.read to block until the stream is closed (
ecv_closed=True) for
=-1 reads, ensuring data is only returned after remote closure.

* fix: raise StreamEOF when reading from closed stream with empty buffer

* fix: prioritize returning buffered data even after stream reset

* fix: prioritize returning buffered data even after stream reset

* fix: Ensure test_net_stream_read_after_remote_closed_and_reset passes in full suite

* fix: Add __init__.py to yamux module to fix documentation build

* fix: Add __init__.py to yamux module to fix documentation build

* fix: Add libp2p.stream_muxer.yamux to libp2p.stream_muxer.rst toctree

* fix: Correct title underline length in libp2p.stream_muxer.yamux.rst

* fix: Add a = so that is matches the libp2p.stream\_muxer.yamux length

* fix(tests): Resolve race condition in network notification test

* fix: fixing failing tests and examples with yamux and noise

* refactor: remove debug logging and improve x25519 tests

* fix: Add functionality for users to choose between Yamux and Mplex

* fix: increased trio sleep to 0.1 sec for slow environment

* feat: Add test for switching between Yamux and mplex

* refactor: move host fixtures to interop tests

* chore: Update __init__.py removing unused import

removed unused
```python
import os
import logging
```

* lint: fix import order

* fix: Resolve conftest.py conflict by removing trio test support

* fix: Resolve test skipping by keeping trio test support

* Fix: add a newline at end of the file

---------

Co-authored-by: acul71 <luca.pisani@birdo.net>
Co-authored-by: acul71 <34693171+acul71@users.noreply.github.com>

tests/utils/factories.py

@@ -98,6 +98,10 @@ from libp2p.stream_muxer.mplex.mplex import (
 from libp2p.stream_muxer.mplex.mplex_stream import (
     MplexStream,
 )
+from libp2p.stream_muxer.yamux.yamux import (
+    Yamux,
+    YamuxStream,
+)
 from libp2p.tools.async_service import (
     background_trio_service,
 )
@@ -197,10 +201,18 @@ def mplex_transport_factory() -> TMuxerOptions:
     return {MPLEX_PROTOCOL_ID: Mplex}
 
 
-def default_muxer_transport_factory() -> TMuxerOptions:
+def default_mplex_muxer_transport_factory() -> TMuxerOptions:
     return mplex_transport_factory()
 
 
+def yamux_transport_factory() -> TMuxerOptions:
+    return {cast(TProtocol, "/yamux/1.0.0"): Yamux}
+
+
+def default_muxer_transport_factory() -> TMuxerOptions:
+    return yamux_transport_factory()
+
+
 @asynccontextmanager
 async def raw_conn_factory(
     nursery: trio.Nursery,
@@ -643,7 +655,8 @@ async def mplex_conn_pair_factory(
     security_protocol: TProtocol = None,
 ) -> AsyncIterator[tuple[Mplex, Mplex]]:
     async with swarm_conn_pair_factory(
-        security_protocol=security_protocol, muxer_opt=default_muxer_transport_factory()
+        security_protocol=security_protocol,
+        muxer_opt=default_mplex_muxer_transport_factory(),
     ) as swarm_pair:
         yield (
             cast(Mplex, swarm_pair[0].muxed_conn),
@@ -669,6 +682,37 @@ async def mplex_stream_pair_factory(
         yield stream_0, stream_1
 
 
+@asynccontextmanager
+async def yamux_conn_pair_factory(
+    security_protocol: TProtocol = None,
+) -> AsyncIterator[tuple[Yamux, Yamux]]:
+    async with swarm_conn_pair_factory(
+        security_protocol=security_protocol, muxer_opt=default_muxer_transport_factory()
+    ) as swarm_pair:
+        yield (
+            cast(Yamux, swarm_pair[0].muxed_conn),
+            cast(Yamux, swarm_pair[1].muxed_conn),
+        )
+
+
+@asynccontextmanager
+async def yamux_stream_pair_factory(
+    security_protocol: TProtocol = None,
+) -> AsyncIterator[tuple[YamuxStream, YamuxStream]]:
+    async with yamux_conn_pair_factory(
+        security_protocol=security_protocol
+    ) as yamux_conn_pair_info:
+        yamux_conn_0, yamux_conn_1 = yamux_conn_pair_info
+        stream_0 = await yamux_conn_0.open_stream()
+        await trio.sleep(0.01)
+        stream_1: YamuxStream
+        async with yamux_conn_1.streams_lock:
+            if len(yamux_conn_1.streams) != 1:
+                raise Exception("Yamux should not have any other stream")
+            stream_1 = tuple(yamux_conn_1.streams.values())[0]
+        yield stream_0, stream_1
+
+
 @asynccontextmanager
 async def net_stream_pair_factory(
     security_protocol: TProtocol = None, muxer_opt: TMuxerOptions = None