Restore IPC transport style conventions

Bring the transport helpers back in line with project style:

- restore single-quote strings and docstrings;
- drop the oversized helper divider and simplify comments;
- keep guarded `match` dispatch so a missing `socket.AF_UNIX`
  remains safe when `HAS_UDS` is false.

Also, format the `HAS_UDS` conjunction with the project's
multiline branch convention.

Review: PR #475 (goodboy)
https://github.com/goodboy/tractor/pull/475

Prompt-IO: ai/prompt-io/opencode/20260817T231825Z_359fe75c_prompt_io.md

(this patch was generated in some part by `opencode` using `gpt-5.6-sol` (`openai`))

ai/prompt-io/opencode/20260817T231825Z_359fe75c_prompt_io.md

@@ -0,0 +1,39 @@
+---
+model: openai/gpt-5.6-sol
+service: opencode
+session: pr475-review-fixes-20260817
+timestamp: 2026-08-17T23:18:25Z
+git_ref: 359fe75c
+scope: code
+substantive: true
+raw_file: 20260817T231825Z_359fe75c_prompt_io.raw.md
+---
+
+## Prompt
+
+Continue the `/code-review-changes` pass for PR #475 in its isolated
+worktree. Address the seven accepted manual-review findings in
+`tractor/ipc/_types.py` and `tractor/ipc/_uds.py`, preserve the existing
+Windows capability behavior, verify the result, and prepare the work for
+human-controlled commit and review-reply steps. Do not publish replies,
+stage, commit, or push without the required explicit authorization.
+
+## Response summary
+
+Restored project quote, docstring, multiline-expression, and
+`match/case` conventions while retaining the Windows-safe UDS guard.
+Removed unnecessary structural and comment churn, then verified the
+focused transport, discovery, and lazy-import paths plus the missing
+`AF_UNIX` behavior.
+
+## Files changed
+
+- `tractor/ipc/_types.py` - restore project style and guarded
+  socket-family dispatch.
+- `tractor/ipc/_uds.py` - format the UDS capability gate
+  consistently.
+
+## Human edits
+
+None - the generated patch remains uncommitted and awaits human
+review.

ai/prompt-io/opencode/20260817T231825Z_359fe75c_prompt_io.raw.md

@@ -0,0 +1,45 @@
+---
+model: openai/gpt-5.6-sol
+service: opencode
+timestamp: 2026-08-17T23:18:25Z
+git_ref: 359fe75c
+diff_cmd: git diff HEAD~1..HEAD
+---
+
+Applied the seven accepted manual-review fixes for PR #475 while
+preserving the Windows transport capability behavior.
+
+> `git diff HEAD~1..HEAD -- tractor/ipc/_types.py`
+
+The generated changes restore the project's single-quote docstring and
+string conventions, remove the unnecessary helper divider, simplify the
+transport-registry comments, and restore `match/case` socket-family
+dispatch. The UDS case retains a `HAS_UDS` guard that short-circuits
+before `socket.AF_UNIX` is evaluated on unsupported hosts. Nearby error
+messages are wrapped without changing their content.
+
+> `git diff HEAD~1..HEAD -- tractor/ipc/_uds.py`
+
+The generated change reformats the `HAS_UDS` conjunction according to
+the project's multiline boolean-expression convention and simplifies
+the adjacent capability comment.
+
+Verification:
+
+`/home/goodboy/repos/tractor/py313/bin/pytest -q tests/test_lazy_imports.py tests/discovery tests/ipc/test_server.py`
+
+Result: `66 passed, 2 xpassed in 60.62s`.
+
+`ruff check --no-cache --output-format=json tractor/ipc/_types.py tractor/ipc/_uds.py`
+
+Result: no findings.
+
+`git diff --check`
+
+Result: no whitespace errors.
+
+An explicit missing-`AF_UNIX` probe set `HAS_UDS = False`, removed the
+socket constant, and exercised an unsupported socket family. It raised
+the expected `NotImplementedError` instead of `AttributeError`.
+
+No review replies, commits, or pushes were published.

tractor/ipc/_types.py

@@ -36,16 +36,14 @@ from tractor.ipc._uds import (
     HAS_UDS,
 )
 
-# the UDS backend is importable everywhere but only *usable* where
-# `trio` reports `has_unix` (i.e. POSIX). On Windows / no-`AF_UNIX`
-# hosts `HAS_UDS` is `False` and the runtime registers TCP only.
+# the UDS backend is importable everywhere but only *usable* when
+# `HAS_UDS` is `True`; otherwise the runtime registers TCP only.
 Address = TCPAddress|UDSAddress
 
 # the available msg-transport backends on this host: TCP always,
-# UDS only where usable (`HAS_UDS`). The lookup maps below are all
-# DERIVED from this single list via each backend's ClassVars
-# (`codec_key`, `address_type`) — register a backend here and every
-# map picks it up; no per-map `if HAS_UDS` to keep in sync.
+# UDS only where usable (`HAS_UDS`). The lookup maps below derive
+# from this single list via each backend's `codec_key` and
+# `address_type`: register a backend here and every map picks it up.
 _msg_transports: list[Type[MsgTransport]] = [
     MsgpackTCPStream,
 ]
@@ -65,55 +63,63 @@ _addr_to_transport: dict[Type[Address], Type[MsgTransport]] = {
 }
 
 
-# ------------------------------------------------------------
-# Helpers
-# ------------------------------------------------------------
 def transport_from_addr(
     addr: Address,
-    codec_key: str = "msgpack",
+    codec_key: str = 'msgpack',
 ) -> Type[MsgTransport]:
-    """
+    '''
     Given a destination address and a desired codec, find the
     corresponding `MsgTransport` type.
-    """
+
+    '''
     try:
-        return _addr_to_transport[type(addr)]  # type: ignore[call-arg]
+        addr_type = type(addr)
+        return _addr_to_transport[addr_type]
+
     except KeyError:
         raise NotImplementedError(
-            f"No known transport for address {repr(addr)}"
+            f'No known transport for address '
+            f'{addr!r}'
         )
 
 
 def transport_from_stream(
     stream: trio.abc.Stream,
-    codec_key: str = "msgpack",
+    codec_key: str = 'msgpack',
 ) -> Type[MsgTransport]:
-    """
+    '''
     Given an arbitrary `trio.abc.Stream` and a desired codec,
     find the corresponding `MsgTransport` type.
-    """
-    transport = None
+
+    '''
+    transport: str|None = None
 
     if isinstance(stream, trio.SocketStream):
         sock: socket.socket = stream.socket
-        fam = sock.family
+        match sock.family:
+            case socket.AF_INET | socket.AF_INET6:
+                transport = 'tcp'
 
-        if fam in (socket.AF_INET, getattr(socket, "AF_INET6", None)):
-            transport = "tcp"
+            # `HAS_UDS` short-circuits before `socket.AF_UNIX` on
+            # hosts where that constant is absent.
+            case fam if (
+                HAS_UDS
+                and
+                fam == socket.AF_UNIX
+            ):
+                transport = 'uds'
 
-        # only consider `AF_UNIX` when the UDS backend is active;
-        # `HAS_UDS` short-circuits before `socket.AF_UNIX` so this
-        # stays safe on hosts where that constant is absent.
-        if transport is None and HAS_UDS and fam == socket.AF_UNIX:  # type: ignore[attr-defined]
-            transport = "uds"
-
-        if transport is None:
-            raise NotImplementedError(f"Unsupported socket family: {fam}")
+            case fam:
+                raise NotImplementedError(
+                    f'Unsupported socket family: {fam}'
+                )
 
     if not transport:
         raise NotImplementedError(
-            f"Could not figure out transport type for stream type {type(stream)}"
+            f'Could not figure out transport type for stream type '
+            f'{type(stream)}'
         )
 
     key = (codec_key, transport)
+
     return _key_to_transport[key]

tractor/ipc/_uds.py

@@ -114,12 +114,13 @@ _SUN_PATH_LIMIT: int = (
 )
 
 
-# single source of truth for "is the UDS backend usable on this
-# host?" Windows can expose `AF_UNIX`, but this backend remains
+# single source of truth for whether the UDS backend is usable on this
+# host. Windows can expose `AF_UNIX`, but this backend remains
 # POSIX-only until its credential and lifecycle paths are supported.
 HAS_UDS: bool = (
     sys.platform != 'win32'
-    and has_unix
+    and
+    has_unix
 )