3 files changed, 130 insertions, 0 deletions
diff --git a/packages/meshbay-node/tests/test_lease_enforcement.py b/packages/meshbay-node/tests/test_lease_enforcement.py
index 2b1014b..7b636ac 100644
--- a/packages/meshbay-node/tests/test_lease_enforcement.py
+++ b/packages/meshbay-node/tests/test_lease_enforcement.py
@@ -273,3 +273,36 @@ async def test_the_sweeper_does_not_reclaim_a_transfer_that_is_moving(group):
     await _request(peer, _ids(group)[0], tr="t1")
     assert slots.leases["t1"].used is True
     await asyncio.sleep(0)
+
+
+# ── the line the node logs when a transfer ends ─────────────────────────────
+
+async def test_a_served_chunk_is_counted_on_its_lease(group):
+    peer = _Session(group)
+    group["_peers"]["s1"] = peer
+    peer._do_transfer_open({"tr": "t1", "kind": DOWNLOAD, "bytes": 2_000_000})
+    await _request(peer, _ids(group)[0], tr="t1")
+    await _request(peer, _ids(group)[0], tr="invented")
+
+    lease = peer._slots().leases["t1"]
+    assert lease.moved == len(peer.chunks()[0]["ct"])
+    line = peer._transfer_end_line(lease, "done")
+    assert line.startswith("transfer: end download t1 done 1.0 MB"), line
+
+
+async def test_a_closed_transfer_is_logged_once(group):
+    peer = _Session(group)
+    group["_peers"]["s1"] = peer
+    lines: list[str] = []
+    end_line = peer._transfer_end_line
+    peer._transfer_end_line = (
+        lambda lease, reason: lines.append(end_line(lease, reason)) or lines[-1])
+
+    peer._do_transfer_open({"tr": "t1", "kind": DOWNLOAD, "bytes": 2_000_000})
+    peer._do_transfer_open({"tr": "t2", "kind": DOWNLOAD, "bytes": 2_000_000})
+    peer._do_transfer_close({"tr": "t1", "reason": "cancelled"})
+    peer._release_transfers()
+    peer._release_transfers()
+
+    assert [x.split()[3:5] for x in lines] == [
+        ["t1", "cancelled"], ["t2", "session_gone"]], lines
diff --git a/packages/meshbay-node/tests/test_sctp_stats.py b/packages/meshbay-node/tests/test_sctp_stats.py
new file mode 100644
index 0000000..bf8970d
--- /dev/null
+++ b/packages/meshbay-node/tests/test_sctp_stats.py
@@ -0,0 +1,74 @@
+"""Losses and T3 expirations are counted per association (see sctp_stats.py).
+
+Replayed against aiortc's own RTCSctpTransport: five chunks sent and the first
+one lost, so three acknowledgements in a row report it missing and the sender
+enters fast recovery, once. Then T3 expires, once.
+"""
+
+import asyncio
+
+from aiortc.rtcsctptransport import RTCSctpTransport, SackChunk
+from meshbay_node.transport.webrtc import sctp_stats
+
+
+class _Dtls:
+    state = "connected"
+
+    def _register_data_receiver(self, *a):
+        pass
+
+
+class _Pc:
+    def __init__(self, sctp):
+        self.sctp = sctp
+
+
+def _sack(cumulative_tsn: int, gaps: list) -> SackChunk:
+    sack = SackChunk()
+    sack.cumulative_tsn = cumulative_tsn % 2**32
+    sack.gaps = gaps
+    sack.duplicates = []
+    sack.advertised_rwnd = 1 << 20
+    return sack
+
+
+async def _replay() -> RTCSctpTransport:
+    s = RTCSctpTransport(_Dtls())
+    s._association_state = s.State.ESTABLISHED
+
+    async def sent(*_a, **_k):
+        pass
+
+    s._send_chunk = sent
+    for name in ("_t3_start", "_t3_restart", "_t3_cancel"):
+        setattr(s, name, lambda: None)
+    s._cwnd = 100_000
+
+    for _ in range(5):
+        await s._send(1, 51, b"x" * 1000)
+    first = s._sent_queue[0].tsn
+    for last_seen in (2, 3, 4):
+        await s._receive_sack_chunk(_sack(first - 1, [(2, last_seen + 1)]))
+    # Still recovering from the same loss: one episode, not a second.
+    await s._receive_sack_chunk(_sack(first - 1, [(2, 5)]))
+    s._t3_expired()
+    return s
+
+
+def test_a_loss_and_a_t3_expiry_are_each_counted_once():
+    s = asyncio.run(_replay())
+    assert s._mb_losses == 1
+    assert s._mb_t3 == 1
+    assert sctp_stats.describe(_Pc(s)).endswith("loss=1 t3=1")
+
+
+def test_an_association_that_lost_nothing_says_so():
+    async def fresh() -> RTCSctpTransport:
+        return RTCSctpTransport(_Dtls())
+
+    s = asyncio.run(fresh())
+    assert sctp_stats.describe(_Pc(s)).endswith("rtt=? loss=0 t3=0")
+
+
+def test_a_session_without_an_association_adds_nothing():
+    assert sctp_stats.describe(None) == ""
diff --git a/packages/meshbay-node/tests/test_transfer_slots.py b/packages/meshbay-node/tests/test_transfer_slots.py
index 08e7e70..68d8858 100644
--- a/packages/meshbay-node/tests/test_transfer_slots.py
+++ b/packages/meshbay-node/tests/test_transfer_slots.py
@@ -369,3 +369,26 @@ def test_using_a_lease_forgives_its_earlier_misses(_=None):
     assert s.leases["slow"].missed_grants == 2
     s.touch("slow", now=2 * GRANT_DEADLINE_SECS + 3)
     assert s.leases["slow"].missed_grants == 0
+
+
+# ── what the end-of-transfer line is built from ─────────────────────────────
+
+def test_a_lease_counts_what_moved_and_for_how_long():
+    slots = TransferSlots()
+    slots.open(tr="t1", kind=DOWNLOAD, session_key="s1", user_id="alice",
+               group_id="g1", now=0.0)
+    slots.touch("t1", now=10.0)
+    slots.account("t1", 1_000_000, now=10.5)
+    slots.touch("t1", now=11.0)
+    slots.account("t1", 500_000, now=12.0)
+    lease = slots.leases["t1"]
+    assert lease.moved == 1_500_000
+    assert lease.elapsed == 2.0
+
+
+def test_a_lease_nothing_moved_under_has_no_duration():
+    slots = TransferSlots()
+    lease, _ = slots.open(tr="t1", kind=DOWNLOAD, session_key="s1",
+                          user_id="alice", group_id="g1", now=0.0)
+    assert (lease.moved, lease.elapsed) == (0, 0.0)
+    slots.account("unknown", 10)