pytest: test for bad estimatefees results.

See: #6183
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

tests/plugins/badestimate.py

@@ -0,0 +1,90 @@
+#!/usr/bin/env python3
+import json
+import subprocess
+
+from pyln.client import Plugin
+
+
+plugin = Plugin()
+
+
+def bcli(plugin, cmd):
+    ret = subprocess.run(['bitcoin-cli',
+                          '-datadir={}'.format(plugin.get_option("bitcoin-datadir")),
+                          '-rpcuser={}'.format(plugin.get_option("bitcoin-rpcuser")),
+                          '-rpcpassword={}'.format(plugin.get_option("bitcoin-rpcpassword")),
+                          '-rpcport={}'.format(plugin.get_option("bitcoin-rpcport"))]
+                         + cmd, stdout=subprocess.PIPE)
+    if ret.returncode != 0:
+        return None
+    return ret.stdout.decode('utf-8')
+
+
+@plugin.method("estimatefees")
+def estimatefees(plugin, **kwargs):
+    if plugin.get_option("badestimate-badorder"):
+        return {"feerate_floor": 1000,
+                "feerates": [{"blocks": 6,
+                              "feerate": 1240000000},
+                             {"blocks": 12,
+                              "feerate": 1350000000},
+                             {"blocks": 100,
+                              "feerate": 3610000000},
+                             {"blocks": 2,
+                              "feerate": 1270000000}]}
+    else:
+        return {"feerate_floor": 1000,
+                "feerates": [{"blocks": 2,
+                              "feerate": 1270000000},
+                             {"blocks": 6,
+                              "feerate": 1240000000},
+                             {"blocks": 12,
+                              "feerate": 1350000000},
+                             {"blocks": 100,
+                              "feerate": 3610000000}]}
+
+
+@plugin.method("getrawblockbyheight")
+def getrawblockbyheight(plugin, height, **kwargs):
+    bhash = bcli(plugin, ["getblockhash", str(height)])
+    if bhash is None:
+        return {"blockhash": None,
+                "block": None}
+    bhash = bhash.strip()
+    block = bcli(plugin, ["getblock", bhash, "0"]).strip()
+    return {"blockhash": bhash,
+            "block": block}
+
+
+@plugin.method("getchaininfo")
+def getchaininfo(plugin, **kwargs):
+    info = json.loads(bcli(plugin, ["getblockchaininfo"]))
+    return {"chain": info['chain'],
+            "headercount": info['headers'],
+            "blockcount": info['blocks'],
+            "ibd": info['initialblockdownload']}
+
+
+@plugin.method("sendrawtransaction")
+def sendrawtransaction(plugin, tx, allowhighfees=False, **kwargs):
+    bcli(plugin, ["sendrawtransaction", tx])
+    return {'success': True}
+
+
+@plugin.method("getutxout")
+def getutxout(plugin, txid, vout, *kwargs):
+    txoutstr = bcli(plugin, ["gettxout", txid, vout]).strip()
+    if txoutstr == "":
+        return {"amount": None, "script": None}
+    txout = json.loads(txoutstr)
+    return {"amount": txout['value'],
+            "script": txout['scriptPubKey']['hex']}
+
+
+plugin.add_option("bitcoin-rpcuser", '', '')
+plugin.add_option("bitcoin-rpcpassword", '', '')
+plugin.add_option("bitcoin-datadir", '', '')
+plugin.add_option("bitcoin-rpcport", '', '')
+plugin.add_option("badestimate-badorder", False, 'Send out-of-order estimates', opt_type='bool')
+
+plugin.run()

tests/test_plugin.py

@@ -1748,6 +1748,34 @@ def test_bitcoin_backend(node_factory, bitcoind):
                                " bitcoind")
 
 
+def test_bitcoin_bad_estimatefee(node_factory, bitcoind):
+    """
+    This tests that we don't crash if bitcoind backend gives bad estimatefees.
+    """
+    plugin = os.path.join(os.getcwd(), "tests/plugins/badestimate.py")
+    l1 = node_factory.get_node(options={"disable-plugin": "bcli",
+                                        "plugin": plugin,
+                                        "badestimate-badorder": True,
+                                        "wumbo": None},
+                               start=False,
+                               may_fail=True, allow_broken_log=True)
+    l1.daemon.start(wait_for_initialized=False, stderr_redir=True)
+    assert l1.daemon.wait() == 1
+    l1.daemon.is_in_stderr(r"badestimate.py error: bad response to estimatefees.feerates \(Blocks must be ascending order: 2 <= 100!\)")
+
+    del l1.daemon.opts["badestimate-badorder"]
+    l1.start()
+
+    l2 = node_factory.get_node(options={"disable-plugin": "bcli",
+                                        "plugin": plugin,
+                                        "wumbo": None})
+    # Give me some funds.
+    bitcoind.generate_block(5)
+    l1.fundwallet(100 * 10**8)
+    l1.connect(l2)
+    l1.rpc.fundchannel(l2.info["id"], 50 * 10**8)
+
+
 def test_bcli(node_factory, bitcoind, chainparams):
     """
     This tests the bcli plugin, used to gather Bitcoin data from a local