test: add initial tests for starting an external fundchannel

Test for getting through the address generation portion.

tests/test_connection.py

@@ -9,6 +9,7 @@ import os
 import pytest
 import time
 import random
+import re
 import shutil
 import unittest
 
@@ -818,6 +819,54 @@ def test_funding_by_utxos(node_factory, bitcoind):
         l1.rpc.fundchannel(l3.info["id"], int(0.01 * 10**8), utxos=utxos)
 
 
+# Check a bunch of preliminary states for calling these RPCs
+def test_funding_external_wallet_corners(node_factory, bitcoind):
+    l1 = node_factory.get_node()
+    l2 = node_factory.get_node()
+
+    amount = 2**24
+    # Fail to open (too large)
+    with pytest.raises(RpcError, match=r'Amount exceeded 16777215'):
+        l1.rpc.fundchannel_start(l2.info['id'], amount)
+
+    amount = amount - 1
+    fake_txid = '929764844a8f9938b669a60a1d51a11c9e2613c7eb4776e4126f1f20c0a685c3'
+
+    with pytest.raises(RpcError, match=r'Unknown peer'):
+        l1.rpc.fundchannel_start(l2.info['id'], amount)
+
+    with pytest.raises(RpcError, match=r'Unknown peer'):
+        l1.rpc.fundchannel_continue(l2.info['id'], fake_txid)
+
+    # Should not be able to continue without being in progress.
+    l1.rpc.connect(l2.info['id'], 'localhost', l2.port)
+    with pytest.raises(RpcError, match=r'No channel funding in progress.'):
+        l1.rpc.fundchannel_continue(l2.info['id'], fake_txid)
+
+
+def test_funding_external_wallet(node_factory, bitcoind):
+    l1 = node_factory.get_node()
+    l2 = node_factory.get_node()
+
+    l1.rpc.connect(l2.info['id'], 'localhost', l2.port)
+    assert(l1.rpc.listpeers()['peers'][0]['id'] == l2.info['id'])
+
+    amount = 2**24 - 1
+    address = l1.rpc.fundchannel_start(l2.info['id'], amount)['funding_address']
+    assert len(address) > 0
+
+    peer = l1.rpc.listpeers()['peers'][0]
+    # Peer should still be connected and in state waiting for funding_txid
+    assert peer['id'] == l2.info['id']
+    r = re.compile('Funding channel start: awaiting funding_txid with output to .*')
+    assert any(r.match(line) for line in peer['channels'][0]['status'])
+    assert 'OPENINGD' in peer['channels'][0]['state']
+
+    # Trying to start a second funding should not work, it's in progress.
+    with pytest.raises(RpcError, match=r'Already funding channel'):
+        l1.rpc.fundchannel_start(l2.info['id'], amount)
+
+
 def test_lockin_between_restart(node_factory, bitcoind):
     l1 = node_factory.get_node(may_reconnect=True)
     l2 = node_factory.get_node(options={'funding-confirms': 3},