Five defects in the chain itself, plus the stale handoff state.
Each consumer now gets its own shallow copy of the typed-edit record.
Handing everyone the same table let a DECLINING consumer rewrite
provenance for the ones behind it, and pairing decides what to close
from `rec.char` — so a forged `char` turned a typed `x` into `x)`.
Every field is a scalar or an opaque id, so a shallow copy is complete.
The fan-out iterates a snapshot of the consumer list. It was iterating
the same array `add_consumer` mutates: a consumer that registered a
lower-priority one shifted itself forward under `ipairs` and ran twice,
and re-registering made that unbounded. Registrations and removals made
during a fan-out now take effect on the next one, stated as a contract
and pinned in both directions.
`tostring` on the caught error moved inside the containment. A Lua
error may be any value, including a table whose `__tostring` throws —
rendering it outside the `pcall` reintroduced exactly the escape the
containment exists to prevent.
Priorities are validated as finite integers in i32 range, matching
`pmacs.completion.register`. NaN is a number and every ordered
comparison with it is false, so a NaN consumer landed wherever the
insertion scan gave up and silently voided the lowest-first ordering
that Q#LN22 depends on.
`add_consumer` returns a handle and `remove_consumer` unregisters it,
reporting whether it was live. Without teardown the chain inherited the
`pmacs.hook.add` callback leak COHERENCE.md §13 already records, and
spread it to every consumer.
Also corrects the rationale the containment was documented with, in the
module, the test, and the framing: an uncontained throw does NOT take
the fan-out's other subscribers down. `run_all_must_succeed`
(src/hook.rs:332) collects errors and continues, so lsp.lua still
flushes didChange. The containment is still required — the throw skips
every later consumer in the chain — but the reason is narrower than
rev 7 claimed.
Criteria 46f (record isolation), 46g (snapshot iteration), and 46h
(lifecycle and priority validation) added; 46d's rationale corrected.
Four new tests, all bite-verified by mutation, each failing only its
target: shared record table (1), live-array iteration (1), unprotected
tostring (1), bare number check (1), no-op removal (2). The suite also
runs green under `--features lua54`.
docs/agent-handoff.md said Stage 4a was awaiting approval while this
branch had it implemented and in review.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011LFvC4FQtux4y32KuevZ7B