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was granted again a millisecond later because there was room, and was revoked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, 48 insertions, 0 deletions

diff --git a/packages/meshbay-node/tests/test_transfer_slots_wire.py b/packages/meshbay-node/tests/test_transfer_slots_wire.py
index afa4582..db8c17a 100644
--- a/packages/meshbay-node/tests/test_transfer_slots_wire.py
+++ b/packages/meshbay-node/tests/test_transfer_slots_wire.py
@@ -236,6 +236,25 @@ async def test_asking_before_anything_has_transferred_is_not_an_error():
     assert snapshot["pools"][DOWNLOAD]["in_use"] == 0
 
 
+@pytest.mark.asyncio
+async def test_the_caps_shown_are_the_operators_before_anything_transfers():
+    """
+    `transfers set 2 2` answers "applied now"; `transfers show` said 0/8 —
+    because the no-pool branch reported the module defaults rather than what the
+    operator had just set. Found by running it against a real node. The previous
+    test asserted the defaults, so it agreed with the bug: an operator would
+    have read that as the hot-swap doing nothing all over again.
+    """
+    from meshbay_node import ops
+
+    class _T:
+        _ctx = {"max_concurrent_downloads": 2, "max_concurrent_uploads": 3}
+
+    snapshot = await ops.list_transfers({"webrtc": _T()})
+    assert snapshot["pools"][DOWNLOAD]["cap"] == 2
+    assert snapshot["pools"][UPLOAD]["cap"] == 3
+
+
 # ── the sweeper's lifetime ──────────────────────────────────────────────────
 
 async def test_the_sweeper_outlives_the_session_that_started_it(ctx):
@@ -296,3 +315,32 @@ async def test_the_sweeper_stops_when_the_last_lease_goes(ctx):
         assert ctx.get("_transfer_sweeper") is None
     finally:
         ws.TRANSFER_SWEEP_SECS = original
+
+
+async def test_a_chunk_request_keeps_its_lease_alive(ctx):
+    """
+    The seam that cost an afternoon. `TransferSlots.touch` existed, was tested,
+    and **nothing ever called it**: the node ignored `tr` on `file_req`
+    entirely, so `used` stayed False for every download ever made and the
+    sweeper revoked each grant 30 s in, while the file was transferring.
+
+    Neither side's tests could see it — the pool was correct, the handlers were
+    correct, and the call between them was missing. Only the node's own log
+    showed it, repeating the same reclaim every 30 s.
+    """
+    peer = _join(ctx, "s1", "alice")
+    peer._do_transfer_open({"tr": "t1", "bytes": 1024})
+    lease = peer._slots().leases["t1"]
+    assert lease.used is False
+
+    # A chunk request for a file that does not exist still counts: what marks
+    # the lease is the peer asking, not the node succeeding.
+    peer._group_ctx()["index"] = None
+    try:
+        await peer._do_file_request({"file_id": "nope", "chunk_index": 0,
+                                     "tr": "t1"})
+    except Exception:
+        pass
+    assert peer._slots().leases["t1"].used is True, (
+        "a chunk request under this lease did not mark it alive; the node will "
+        "revoke the grant in 30 seconds")