CFG-01 review: widen the rule, refuse the firmware-veto case, fix the stop footgun

Review findings, all confirmed in code before changing anything.

THE RULE DID NOT AUTHORISE ITS OWN BEST REFUSAL. The stated test was
"makes a safety mechanism inoperative, or makes a stated limit untrue",
and a blank setpoint_entity does neither - layer 1 pinning the inverter
at 0 W is the failsafe WORKING, as validate.py's own text admitted. The
real justification is a second, separate category: the add-on is inert
and indistinguishable from healthy. Stated as (a) and (b), with each
refusal tagged, and with both halves explicitly bounded - (a) is not
"any two numbers that could disagree", (b) is not "anything degraded".
Left implicit, the gap is where trivia-creep comes back in.

meter_max_age_s ABOVE THE FIRMWARE'S VETO IS NOW REFUSED. The schema
allows int(5,300); the firmware's threshold is a compile-time
`max_age_s: "30"` and it trips layer 1 at `p1_age_s >= 30`. At 120 the
add-on believes a 119 s reading is fresh and keeps commanding while the
board has already vetoed and is holding at 0 W - healthy meter, running
controller, nothing moving. Structurally identical to the max_w case,
and unlike max_w it is settable on this install, so the headline
behaviour finally has a live demonstration. That firmware file's own
comment says a lower bound on this "belongs in CFG-01, not here".

Only ABOVE is refused: below the veto the add-on gives up first, which
is fail-safe and visible on its own status page. Scoped to P1 being
enabled, because meter_max_age_s governs nothing otherwise.
FIRMWARE_INGEST_VETO_S cannot be imported from a compile-time YAML
substitution, so it carries a note on the single direction in which it
can go stale - and a warning that TEL-06 is editing `ingest_stale`, so a
matching integer may stop meaning a matching rule.

stop= WAS A LIVE FOOTGUN. It defaulted to None, which made a Controller
that cannot stop itself the DEFAULT one. On the late-refusal path that
meant: log the banner, return, and leave the process alive forever with
no control loop and no exit - the exact "inert but looks healthy"
failure this module exists to refuse. Now required and keyword-only, so
the broken shape does not construct; test_p1.py's five call sites pass
an Event.

That whole path had no test and no live demo. It has one now: it drives
run_control() against a device that only reports a narrower range once
the loop starts, and asserts it refuses, signals, returns, and writes
NOTHING - plus the converse, that an agreeing device leads to real
writes. This also covers the max_w composition that cannot be reached
through the Supervisor on the live install.

max_w <= 0 is refused. Schema-blocked in production, but
validate_startup_config() is the simulation suite's entry point too, and
a non-positive max_w inverts the arbiter's supervised bounds into a
contradiction that reads as a safety trip rather than a typo.

Verified live 2026-08-28 (backup goodwe_controller-cfg01r2-1787940076):
meter_max_age_s 120 refused with a message naming 120, 30, and THE
FIRMWARE WINS; no traceback; add-on restored byte-exact and running.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Du77usMj8XNKNFZGmUiWDa

goodwe_controller/test_validate.py

@@ -7,10 +7,12 @@ a validator dies is not by missing a fault, it is by refusing something harmless
 until somebody deletes the call.
 """
 
+import asyncio
 import sys
 
 from app.validate import (
-    ACTUATOR_WRITE_KEYS, ConfigRefused, refuse, validate_startup_config,
+    ACTUATOR_WRITE_KEYS, FIRMWARE_INGEST_VETO_S, ConfigRefused, refuse,
+    validate_startup_config,
 )
 
 fails = []
@@ -120,6 +122,47 @@ check("a misspelt meter_source is refused rather than silently ignored",
       why(validate_startup_config(base(meter_source="ha_signd"), -5000, 5000),
           "is not one of"))
 
+# --------------------------------------------------------------------------- #
+print("4. meter_max_age_s against the firmware's compile-time veto")
+# ⚠️ The schema allows int(5,300); the firmware's threshold is baked in at 30 s
+# and wins silently. Same shape as the max_w case: a configured bound overridden
+# by a lower layer, with nothing saying so.
+hw = dict(meter_source="homewizard_local", p1_host="m")
+p = validate_startup_config(base(**hw, meter_max_age_s=120), -5000, 5000)
+check("a meter_max_age_s above the firmware veto is refused", len(p) == 1)
+check("...naming the configured value", why(p, "120"))
+check("...naming the firmware's value", why(p, "30"))
+check("...and saying which one wins", why(p, "THE FIRMWARE WINS"))
+check("the tested pair 30/30 is accepted",
+      validate_startup_config(base(**hw, meter_max_age_s=30), -5000, 5000) == [])
+check("one second above it is refused",
+      validate_startup_config(base(**hw, meter_max_age_s=31), -5000, 5000) != [])
+# Below the veto the add-on gives up FIRST, which is fail-safe and visible on
+# its own status page. Only above is the silent case.
+check("below the veto is fine - the add-on being stricter is not a conflict",
+      validate_startup_config(base(**hw, meter_max_age_s=10,
+                                   meter_poll_s=4), -5000, 5000) == [])
+# ⚠️ Scope: meter_max_age_s is read by nothing but P1Ingest, and the veto keys
+# off a sensor only published when ingestion runs. With the meter off it governs
+# nothing, so refusing would be pure trivia.
+check("with meter_source off the number governs nothing and is not refused",
+      validate_startup_config(base(meter_source="off", meter_max_age_s=300),
+                              -5000, 5000) == [])
+check("the constant is the firmware's, not a rounded guess",
+      FIRMWARE_INGEST_VETO_S == 30.0)
+
+# --------------------------------------------------------------------------- #
+print("max_w must be a positive magnitude")
+# Schema-blocked on a real install, but validate_startup_config() is also
+# sim/inject.py's entry point and can be handed any dict at all.
+for bad in (0, -1, -2000):
+    p = validate_startup_config(base(max_w=bad), -5000, 5000)
+    check(f"max_w {bad} is refused", len(p) == 1 and why(p, "must be positive"))
+check("...and the message explains it would read as a trip, not a mistake",
+      why(validate_startup_config(base(max_w=0), -5000, 5000), "contradiction"))
+check("the smallest sane max_w still starts",
+      validate_startup_config(base(max_w=1), -5000, 5000) == [])
+
 # --------------------------------------------------------------------------- #
 print("what must NOT be refused - a validator that fires on trivia gets deleted")
 # DOCS.md: the arbiter's `supervised` limit still binds the wire to +-max_w, so
@@ -153,6 +196,111 @@ err = ConfigRefused(p)
 check("ConfigRefused carries every problem", err.problems == p)
 check("...and str() names one of them", str(err) == p[0])
 
+# --------------------------------------------------------------------------- #
+print("the LATE refusal, when the device only shows up after the gate has run")
+# ⚠️ This path had no test at all and no live demonstration - the review's
+# catch. ESPHome is routinely not up when the add-on boots, so hass.limits()
+# returns (None, None), the range checks are skipped, and run_control() is the
+# first place the device's real rating is ever known. Everything below is about
+# what happens when it turns out to conflict.
+from app.main import Controller            # noqa: E402
+
+
+class _LateHass:
+    """Reports the range only run_control() gets to see."""
+
+    def __init__(self, lo, hi):
+        self.lo, self.hi = lo, hi
+        self.writes = []
+
+    async def limits(self, entity):
+        return (self.lo, self.hi, 1.0)
+
+    async def number(self, *a, **k):
+        return 0.0
+
+    async def set_number(self, entity, value):
+        self.writes.append(value)
+        return True
+
+
+class _Store2:
+    data = {}
+
+    def set(self, *a):
+        pass
+
+
+class _Pub2:
+    enabled = False
+
+    def publish(self, *a, **k):
+        pass
+
+    def close(self):
+        pass
+
+
+def late(opts_over, lo, hi):
+    """Drive run_control() against a device that only reports (lo, hi) now.
+
+    ⚠️ Returns whether run_control() EXITED ON ITS OWN. That is the assertion
+    that matters: on a refusal it must return without entering the while loop,
+    and on a clean config it must not return at all. So the clean case is stopped
+    from outside after it has had time to write, rather than waited on - a
+    wait_for() here would just time out, which is the correct behaviour dressed
+    up as a failure.
+    """
+    async def go():
+        stop = asyncio.Event()
+        hass = _LateHass(lo, hi)
+        # A device narrower than the shipped 5000 W schema ceiling is exactly
+        # the case that cannot be reached through the Supervisor on the live
+        # install, so it is reached here instead.
+        c = Controller(base(**opts_over), hass, _Store2(), _Pub2(), stop=stop)
+        c.auto = True
+        task = asyncio.create_task(c.run_control())
+        for _ in range(30):                    # up to ~3 s
+            if task.done():
+                break
+            await asyncio.sleep(0.1)
+        exited = task.done()
+        if not exited:
+            c.stopping = True
+        await asyncio.wait_for(task, timeout=5)
+        return c, stop, hass, exited
+    return asyncio.run(go())
+
+c, stop, hass, exited = late({"max_w": 5000}, -3600.0, 3600.0)
+check("a device narrower than max_w, discovered late, is refused",
+      c.refused is not None and len(c.refused) == 1)
+check("...naming both values", why(c.refused, "5000") and why(c.refused, "3600"))
+check("...signalling amain to wind down", stop.is_set())
+check("...and returning instead of looping forever", exited)
+# The whole point: run_control() must not fall through into the while loop. A
+# single write here would mean it commanded the inverter under a config it had
+# just declared unusable.
+check("...having never entered the control loop, so it wrote nothing",
+      hass.writes == [])
+check("...and it is recorded in the event log an operator reads",
+      any("REFUSED" in e for e in c.events))
+
+# The same path when there is no conflict: it must NOT refuse, and it must
+# actually regulate - asserted by a write reaching the device, not by absence.
+c2, stop2, hass2, exited2 = late({"max_w": 2000}, -5000.0, 5000.0)
+check("a late device that agrees does not trip the re-check", c2.refused is None)
+check("...and the control loop runs, writing to the device", hass2.writes != [])
+check("...and does not signal a shutdown", not stop2.is_set() and not exited2)
+
+# ⚠️ THE FOOTGUN THE REVIEW FOUND. `stop` used to default to None, so this
+# construction was legal and the refusal path then returned into a live process
+# with no control loop, no exit and no further output.
+try:
+    Controller(base(), _LateHass(-5000.0, 5000.0), _Store2(), _Pub2())
+    check("a Controller with no stop Event is rejected at construction", False)
+except TypeError:
+    check("a Controller with no stop Event is rejected at construction", True)
+
 # --------------------------------------------------------------------------- #
 print()
 if fails: