From a7b1ee34ef3e17e56e9f0cc87f21e0d6a43553e9 Mon Sep 17 00:00:00 2001
From: goodboy <goodboy_foss@protonmail.com>
Date: Thu, 23 Apr 2026 18:30:11 -0400
Subject: [PATCH] Restore fn-arg `_runtime_vars` in `trio_proc` teardown
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During the Phase A extraction of `trio_proc()` out of
`spawn._spawn` into its own submod, the
`debug.maybe_wait_for_debugger(child_in_debug=...)` call site in
the hard-reap `finally` got refactored from the original
`_runtime_vars.get('_debug_mode', ...)` (the fn parameter — the
dict that was constructed by the *parent* for the *child*'s
`SpawnSpec`) to `get_runtime_vars().get(...)` (a global getter that
returns the *parent's* live `_state`). Those are semantically
different — the first asks "is the child we just spawned in debug
mode?", the second asks "are *we* in debug mode?". Under
mixed-debug-mode trees the swap can incorrectly skip (or
unnecessarily delay) the debugger-lock wait during teardown.

Revert to the fn-parameter lookup and add an inline `NOTE` comment
calling out the distinction so it's harder to regress again.

Deats,
- `spawn/_trio.py`: `child_in_debug=get_runtime_vars().get(...)` →
  `child_in_debug=_runtime_vars.get(...)` at the
  `debug.maybe_wait_for_debugger(...)` call in the hard-reap block;
  add 4-line `NOTE` explaining the parent-vs-child distinction.
- `spawn/__init__.py`: drop trailing whitespace after the
  `'mp_forkserver'` docstring bullet.
- `ai/prompt-io/prompts/subints_spawner.md`: drop duplicated `with`
  in `"as with with subprocs"` prose (copilot grammar catch).

Review: PR #444 (Copilot)
https://github.com/goodboy/tractor/pull/444#pullrequestreview-4165928469

(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code
---
 ai/prompt-io/prompts/subints_spawner.md | 2 +-
 tractor/spawn/__init__.py               | 2 +-
 tractor/spawn/_trio.py                  | 6 +++++-
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/ai/prompt-io/prompts/subints_spawner.md b/ai/prompt-io/prompts/subints_spawner.md
index 4911a930..08d38684 100644
--- a/ai/prompt-io/prompts/subints_spawner.md
+++ b/ai/prompt-io/prompts/subints_spawner.md
@@ -24,7 +24,7 @@ Part of this work should include,
     is happening under the hood with how cpython implements subints.
 
   * default configuration should encourage state isolation as with
-    with subprocs, but explicit public escape hatches to enable rigorously
+    subprocs, but explicit public escape hatches to enable rigorously
     managed shm channels for high performance apps.
 
 - all tests should be (able to be) parameterized to use the new
diff --git a/tractor/spawn/__init__.py b/tractor/spawn/__init__.py
index 3f363889..cb9be559 100644
--- a/tractor/spawn/__init__.py
+++ b/tractor/spawn/__init__.py
@@ -29,7 +29,7 @@ coroutine registered in `_spawn._methods`):
 - `._mp`: the stdlib `multiprocessing` backend variants — driven by
   the `mp.context` bound to `_spawn._ctx`:
   * `'mp_spawn'`,
-  * `'mp_forkserver'` 
+  * `'mp_forkserver'`
 
 Entry-point helpers live in `._entry`/`._mp_fixup_main`/
 `._forkserver_override`.
diff --git a/tractor/spawn/_trio.py b/tractor/spawn/_trio.py
index bdb97c75..3b425256 100644
--- a/tractor/spawn/_trio.py
+++ b/tractor/spawn/_trio.py
@@ -246,7 +246,11 @@ async def trio_proc(
                             await proc.wait()
 
                 await debug.maybe_wait_for_debugger(
-                    child_in_debug=get_runtime_vars().get(
+                    # NOTE: use the child's `_runtime_vars`
+                    # (the fn-arg dict shipped via `SpawnSpec`)
+                    # — NOT `get_runtime_vars()` which returns
+                    # the *parent's* live runtime state.
+                    child_in_debug=_runtime_vars.get(
                         '_debug_mode', False
                     ),
                     header_msg=(