feat(V2): ClientRegistry lazy con lock per chiave

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/unit/test_client_registry.py

@@ -0,0 +1,87 @@
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+
+@pytest.mark.asyncio
+async def test_registry_lazy_build():
+    from cerbero_mcp.client_registry import ClientRegistry
+
+    builds: list[tuple[str, str]] = []
+
+    async def fake_build(exchange: str, env: str):
+        builds.append((exchange, env))
+
+        class C:
+            async def aclose(self):
+                pass
+        return C()
+
+    reg = ClientRegistry(builder=fake_build)
+    c = await reg.get("deribit", "testnet")
+    assert builds == [("deribit", "testnet")]
+    assert (await reg.get("deribit", "testnet")) is c  # cached
+    assert builds == [("deribit", "testnet")]
+
+
+@pytest.mark.asyncio
+async def test_registry_different_keys_different_clients():
+    from cerbero_mcp.client_registry import ClientRegistry
+
+    async def fake_build(exchange: str, env: str):
+        class C:
+            tag = (exchange, env)
+            async def aclose(self): ...
+        return C()
+
+    reg = ClientRegistry(builder=fake_build)
+    a = await reg.get("deribit", "testnet")
+    b = await reg.get("deribit", "mainnet")
+    c = await reg.get("bybit", "testnet")
+    assert a is not b
+    assert a.tag == ("deribit", "testnet")
+    assert b.tag == ("deribit", "mainnet")
+    assert c.tag == ("bybit", "testnet")
+
+
+@pytest.mark.asyncio
+async def test_registry_concurrent_get_one_build():
+    from cerbero_mcp.client_registry import ClientRegistry
+
+    counter = {"calls": 0}
+
+    async def fake_build(exchange: str, env: str):
+        counter["calls"] += 1
+        await asyncio.sleep(0.05)
+
+        class C:
+            async def aclose(self): ...
+        return C()
+
+    reg = ClientRegistry(builder=fake_build)
+    results = await asyncio.gather(
+        *[reg.get("deribit", "testnet") for _ in range(10)]
+    )
+    assert counter["calls"] == 1
+    assert all(r is results[0] for r in results)
+
+
+@pytest.mark.asyncio
+async def test_registry_aclose_calls_all():
+    from cerbero_mcp.client_registry import ClientRegistry
+
+    closed: list[tuple[str, str]] = []
+
+    async def fake_build(exchange: str, env: str):
+        class C:
+            async def aclose(self):
+                closed.append((exchange, env))
+        return C()
+
+    reg = ClientRegistry(builder=fake_build)
+    await reg.get("deribit", "testnet")
+    await reg.get("bybit", "mainnet")
+    await reg.aclose()
+    assert sorted(closed) == sorted([("deribit", "testnet"), ("bybit", "mainnet")])