Improve comments/logging in p2p-versionbits-warning.py

Author: jnewbery

test/functional/feature_versionbits_warning.py

@@ -19,6 +19,7 @@
 VB_THRESHOLD = 108        # versionbits activation threshold for regtest
 VB_TOP_BITS = 0x20000000
 VB_UNKNOWN_BIT = 27       # Choose a bit unassigned to any deployment
+VB_UNKNOWN_VERSION = VB_TOP_BITS | (1 << VB_UNKNOWN_BIT)
 
 WARN_UNKNOWN_RULES_MINED = "Unknown block versions being mined! It's possible unknown rules are in effect"
 WARN_UNKNOWN_RULES_ACTIVE = "unknown new rules activated (versionbit {})".format(VB_UNKNOWN_BIT)
@@ -41,8 +42,8 @@ def setup_network(self):
         self.extra_args = [["-alertnotify=echo %s >> \"" + self.alert_filename + "\""]]
         self.setup_nodes()
 
-    # Send numblocks blocks via peer with version set.
     def send_blocks_with_version(self, peer, numblocks, version):
+        """Send numblocks blocks to peer with version set"""
         tip = self.nodes[0].getbestblockhash()
         height = self.nodes[0].getblockcount()
         block_time = self.nodes[0].getblockheader(tip)["time"] + 1
@@ -59,47 +60,42 @@ def send_blocks_with_version(self, peer, numblocks, version):
         peer.sync_with_ping()
 
     def test_versionbits_in_alert_file(self):
+        """Test that the versionbits warning has been written to the alert file.
+
+        Note that this is only called after the node is shutdown, so doesn't need
+        a wait_until wrapper."""
         with open(self.alert_filename, 'r', encoding='utf8') as f:
             alert_text = f.read()
         assert(VB_PATTERN.match(alert_text))
 
     def run_test(self):
-        # Setup the p2p connection and start up the network thread.
         self.nodes[0].add_p2p_connection(TestNode())
-
         network_thread_start()
-
-        # Test logic begins here
         self.nodes[0].p2p.wait_for_verack()
 
-        # 1. Have the node mine one period worth of blocks
+        # Mine one period worth of blocks
         self.nodes[0].generate(VB_PERIOD)
 
-        # 2. Now build one period of blocks on the tip, with < VB_THRESHOLD
-        # blocks signaling some unknown bit.
-        version = VB_TOP_BITS | (1 << VB_UNKNOWN_BIT)
-        self.send_blocks_with_version(self.nodes[0].p2p, VB_THRESHOLD - 1, version)
-
-        # Fill rest of period with regular version blocks
+        self.log.info("Check that there is no warning if previous VB_BLOCKS have <VB_THRESHOLD blocks with unknown versionbits version.")
+        # Build one period of blocks with < VB_THRESHOLD blocks signaling some unknown bit
+        self.send_blocks_with_version(self.nodes[0].p2p, VB_THRESHOLD - 1, VB_UNKNOWN_VERSION)
         self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD + 1)
-        # Check that we're not getting any versionbit-related errors in
-        # get*info()
+
+        # Check that we're not getting any versionbit-related errors in get*info()
         assert(not VB_PATTERN.match(self.nodes[0].getmininginfo()["warnings"]))
         assert(not VB_PATTERN.match(self.nodes[0].getnetworkinfo()["warnings"]))
 
-        # 3. Now build one period of blocks with >= VB_THRESHOLD blocks signaling
-        # some unknown bit
-        self.send_blocks_with_version(self.nodes[0].p2p, VB_THRESHOLD, version)
+        # Build one period of blocks with VB_THRESHOLD blocks signaling some unknown bit
+        self.send_blocks_with_version(self.nodes[0].p2p, VB_THRESHOLD, VB_UNKNOWN_VERSION)
         self.nodes[0].generate(VB_PERIOD - VB_THRESHOLD)
-        # Might not get a versionbits-related alert yet, as we should
-        # have gotten a different alert due to more than 51/100 blocks
-        # being of unexpected version.
-        # Check that get*info() shows some kind of error.
+
+        self.log.info("Check that there is a warning if <50 blocks in the last 100 were an unknown version")
+        # Check that get*info() shows the 51/100 unknown block version error.
         assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getmininginfo()["warnings"])
         assert(WARN_UNKNOWN_RULES_MINED in self.nodes[0].getnetworkinfo()["warnings"])
 
         # Mine a period worth of expected blocks so the generic block-version warning
-        # is cleared, and restart the node. This should move the versionbit state
+        # is cleared, and restart the node. This will move the versionbit state
         # to ACTIVE.
         self.nodes[0].generate(VB_PERIOD)
         self.stop_nodes()
@@ -108,6 +104,7 @@ def run_test(self):
             pass
         self.start_nodes()
 
+        self.log.info("Check that there is a warning if previous VB_BLOCKS have >=VB_THRESHOLD blocks with unknown versionbits version.")
         # Connecting one block should be enough to generate an error.
         self.nodes[0].generate(1)
         assert(WARN_UNKNOWN_RULES_ACTIVE in self.nodes[0].getmininginfo()["warnings"])