fix(node): a running transfer keeps its slot, and a dead grant lets go

Two defects in the lease machinery, both found in the node's own log, neither
reachable from any test on either side.

**`touch()` was never called.** The node ignored `tr` on `file_req` entirely, so
`used` stayed False for every download ever made and the sweeper revoked each
grant thirty seconds in — while the file was transferring at 20 MB/s. The pool
was correct and the handlers were correct; the call between them was missing,
which is why neither side's tests could see it.

**The requeue was a permanent cycle.** A revoked grant went back in the queue,
was granted again a millisecond later because there was room, and was revoked
again thirty seconds on. The node logged the same two reclaims every thirty
seconds for as long as it ran — minutes after the transfers involved had
finished. Three chances now, then the lease is closed and the peer told.
`test_the_counter_never_drifts` could not have caught it: nothing drifted, the
same lease simply never left.

A lease that starts being used forgets its earlier misses: a client that took
two grants to get going is slow, not abandoned.

Also `transfers show` reported the module defaults rather than the operator's
values until something had transferred, so `transfers set 2 2` answered
"applied now" and the next line said 0/8 — indistinguishable, from outside,
from the hot-swap that did nothing for months. The test asserted the defaults
and so agreed with the bug; found by typing the command.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HCGdheDLxGReuKHga3BtST

1 files changed, 58 insertions, 1 deletions

diff --git a/packages/meshbay-node/tests/test_transfer_slots.py b/packages/meshbay-node/tests/test_transfer_slots.py
index a0ef381..7056e93 100644
--- a/packages/meshbay-node/tests/test_transfer_slots.py
+++ b/packages/meshbay-node/tests/test_transfer_slots.py
@@ -24,7 +24,8 @@ import pytest
 
 from meshbay_node.transfers import (
     DOWNLOAD, GRANT_DEADLINE_SECS, IDLE_TIMEOUT_SECS, KINDS,
-    MAX_QUEUED_PER_MEMBER, REASON_IDLE, REASON_NOT_TAKEN_UP, TransferSlots,
+    MAX_MISSED_GRANTS, MAX_QUEUED_PER_MEMBER, REASON_ABANDONED, REASON_IDLE,
+    REASON_NOT_TAKEN_UP, TransferSlots,
     UPLOAD,
 )
 
@@ -306,3 +307,59 @@ def test_the_counter_never_drifts(seed):
     assert s.leases == {}
     assert all(q == [] for q in s.queues.values())
     assert all(s.in_use(k) == 0 for k in KINDS)
+
+
+# ── the cycle the node's own log showed ─────────────────────────────────────
+
+def test_a_grant_is_not_requeued_for_ever(_=None):
+    """
+    A revoked grant went back in the queue, was granted again a millisecond
+    later because there was room, and was revoked again 30 s on. The node
+    logged the same two reclaims every 30 s for as long as it ran — minutes
+    after the transfers involved had finished.
+
+    Three chances, then it is closed and the peer told, which is what ends the
+    cycle. `test_the_counter_never_drifts` could not see this: nothing drifted,
+    the same lease simply never left.
+    """
+    s = _slots(node=4, per_member=4)
+    _open(s, "ghost", now=0.0)
+    now = 0.0
+    reasons = []
+    for _ in range(6):
+        now += GRANT_DEADLINE_SECS + 1
+        ended, _granted = s.sweep(now=now)
+        reasons += [r for _, r in ended]
+    assert reasons.count(REASON_NOT_TAKEN_UP) == MAX_MISSED_GRANTS - 1
+    assert reasons.count(REASON_ABANDONED) == 1
+    assert "ghost" not in s.leases, "the lease is still cycling"
+    assert s.queues[DOWNLOAD] == []
+
+
+def test_a_transfer_that_is_running_is_never_revoked(_=None):
+    """
+    The other half, and the one that mattered: nothing marked a lease used, so
+    `used` stayed False for a whole download and the sweeper revoked a grant
+    every 30 s while the file transferred at 20 MB/s.
+    """
+    s = _slots(node=2, per_member=2)
+    _open(s, "live", now=0.0)
+    now = 0.0
+    for _ in range(10):
+        now += GRANT_DEADLINE_SECS - 5
+        assert s.touch("live", now=now), "a granted lease refused a touch"
+        ended, _granted = s.sweep(now=now)
+        assert ended == [], f"a running transfer was revoked: {ended}"
+    assert s.leases["live"].state == "granted"
+
+
+def test_using_a_lease_forgives_its_earlier_misses(_=None):
+    """A slow start is not an abandoned one: a client that took two grants to
+    get going must not be closed on its third."""
+    s = _slots(node=2, per_member=2)
+    _open(s, "slow", now=0.0)
+    s.sweep(now=GRANT_DEADLINE_SECS + 1)
+    s.sweep(now=2 * GRANT_DEADLINE_SECS + 2)
+    assert s.leases["slow"].missed_grants == 2
+    s.touch("slow", now=2 * GRANT_DEADLINE_SECS + 3)
+    assert s.leases["slow"].missed_grants == 0