added double response test (#80)

* added double response test

* moved to existing file

tests/libp2p/test_libp2p.py

@@ -23,7 +23,6 @@ async def test_simple_messages():
 
     stream = await node_a.new_stream("node_b", "/echo/1.0.0")
     messages = ["hello" + str(x) for x in range(10)]
-
     for message in messages:
         await stream.write(message.encode())
 
@@ -34,3 +33,44 @@ async def test_simple_messages():
 
     # Success, terminate pending tasks.
     return
+
+@pytest.mark.asyncio
+async def test_double_response():
+    hostA = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8002/ipfs/hostA"])
+    hostB = await new_node(transport_opt=["/ip4/127.0.0.1/tcp/8003/ipfs/hostB"])
+
+    async def stream_handler(stream):
+        while True:
+            read_string = (await stream.read()).decode()
+            print("host B received:" + read_string)
+
+            response = "ack1:" + read_string
+            print("sending response:" + response)
+            await stream.write(response.encode())
+
+            response = "ack2:" + read_string
+            print("sending response:" + response)
+            await stream.write(response.encode())
+
+    hostB.set_stream_handler("/echo/1.0.0", stream_handler)
+
+    # Associate the peer with local ip address (see default parameters of Libp2p())
+    hostA.get_peerstore().add_addr("hostB", "/ip4/127.0.0.1/tcp/8003", 10)
+    print("hostA about to open stream")
+    stream = await hostA.new_stream("hostB", "/echo/1.0.0")
+    messages = ["hello" + str(x) for x in range(10)]
+    for message in messages:
+        await stream.write(message.encode())
+
+        response1 = (await stream.read()).decode()
+
+        print("res1: " + response1)
+        assert response1 == ("ack1:" + message)
+
+        response2 = (await stream.read()).decode()
+
+        print("res2: " + response2)
+        assert response2 == ("ack2:" + message)
+
+    # Success, terminate pending tasks.
+    return