test_addfunds_from_block: fix test flakiness.

If you run locally, it fails occasionally; presumably because it
sees previous funds.  Use a random HSM key for that teste.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

tests/test_lightningd.py

@@ -91,7 +91,7 @@ class NodeFactory(object):
         self.executor = executor
         self.bitcoind = bitcoind
 
-    def get_node(self, disconnect=None, options=None, may_fail=False):
+    def get_node(self, disconnect=None, options=None, may_fail=False, random_hsm=False):
         node_id = self.next_id
         self.next_id += 1
 
@@ -100,7 +100,7 @@ class NodeFactory(object):
 
         socket_path = os.path.join(lightning_dir, "lightning-rpc").format(node_id)
         port = 16330+node_id
-        daemon = utils.LightningD(lightning_dir, self.bitcoind.bitcoin_dir, port=port)
+        daemon = utils.LightningD(lightning_dir, self.bitcoind.bitcoin_dir, port=port, random_hsm=random_hsm)
         # If we have a disconnect string, dump it to a file for daemon.
         if disconnect:
             with open(os.path.join(lightning_dir, "dev_disconnect"), "w") as f:
@@ -2097,7 +2097,9 @@ class LightningDTests(BaseLightningDTests):
     def test_addfunds_from_block(self):
         """Send funds to the daemon without telling it explicitly
         """
-        l1 = self.node_factory.get_node()
+        # Previous runs with same bitcoind can leave funds!
+        l1 = self.node_factory.get_node(random_hsm=True)
+
         addr = l1.rpc.newaddr()['address']
         txid = l1.bitcoin.rpc.sendtoaddress(addr, 0.1)
         l1.bitcoin.rpc.generate(1)

tests/utils.py

@@ -231,7 +231,7 @@ class BitcoinD(TailableProc):
 # lightning-5 => 032cf15d1ad9c4a08d26eab1918f732d8ef8fdc6abb9640bf3db174372c491304e aka SOMBERFIRE #032cf1
 
 class LightningD(TailableProc):
-    def __init__(self, lightning_dir, bitcoin_dir, port=9735):
+    def __init__(self, lightning_dir, bitcoin_dir, port=9735, random_hsm=False):
         TailableProc.__init__(self, lightning_dir)
         self.lightning_dir = lightning_dir
         self.port = port
@@ -246,8 +246,9 @@ class LightningD(TailableProc):
             '--network=regtest'
         ]
         if DEVELOPER:
-            self.cmd_line += ['--dev-broadcast-interval=1000',
-                              '--dev-hsm-seed={}'.format(seed.hex())]
+            self.cmd_line += ['--dev-broadcast-interval=1000']
+            if not random_hsm:
+                self.cmd_line += ['--dev-hsm-seed={}'.format(seed.hex())]
         self.cmd_line += ["--{}={}".format(k, v) for k, v in LIGHTNINGD_CONFIG.items()]
         self.prefix = 'lightningd(%d)' % (port)