Merge #19804: test/refactor: reference p2p objects explicitly and remove confusing Test_Node.p2p property

10d61505fe77880d6989115defa5e08417f3de2d [test] remove confusing p2p property (gzhao408)
549d30faf04612d9589c81edf9770c99e3221885 scripted-diff: replace p2p with p2ps[0] in p2p_invalid_tx (gzhao408)
7a0de46aeafb351cffa3410e1aae9809fd4698ad [doc] sample code for test framework p2p objects (gzhao408)
784f757994c1306bb6584b14c0c78617d6248432 [refactor] clarify tests by referencing p2p objects directly (gzhao408)

Pull request description:

  The `TestNode` has a `p2p` property which is an alias for `p2ps[0]`.

  I think this should be removed because it can be confusing and misleading (to both the test writer and reviewer), especially if a TestNode has multiple p2ps connected (which is the case for many tests).
  Another example is when a test has multiple subtests that connect 1 p2p and use the `p2p` property to reference it. If the subtests don't completely clean up after themselves, the subtests may affect one another.

  The best way to refer to a connected p2p is use the object returned by `add_p2p_connection` like this:
  ```py
  p2p_conn = node.add_p2p_connection(P2PInterface())
  ```
  A good example is [p2p_invalid_locator.py](https://github.com/bitcoin/bitcoin/blob/master/test/functional/p2p_invalid_locator.py), which cleans up after itself (waits in both `wait_for_disconnect` and in `disconnect_p2ps`) but wouldn't need so much complexity if it just referenced the connections directly.

  If there is only one connected, it's not really that tedious to just use `node.p2ps[0]` instead of `node.p2p` (and it can always be aliased inside the test itself).

ACKs for top commit:
  robot-dreams:
    utACK 10d61505fe77880d6989115defa5e08417f3de2d
  jnewbery:
    utACK 10d61505fe77880d6989115defa5e08417f3de2d
  guggero:
    Concept ACK 10d61505.

Tree-SHA512: 5965548929794ec660dae03467640cb2156d7d826cefd26d3a126472cbc2494b855c1d26bbb7b412281fbdc92b9798b9765a85c27bc1a97f7798f27f64db6f13

1 files changed, 7 insertions, 7 deletions

diff --git a/test/functional/feature_dersig.py b/test/functional/feature_dersig.py
index f263c93c8a..3f7efdbded 100755
--- a/test/functional/feature_dersig.py
+++ b/test/functional/feature_dersig.py
@@ -59,7 +59,7 @@ class BIP66Test(BitcoinTestFramework):
         )
 
     def run_test(self):
-        self.nodes[0].add_p2p_connection(P2PInterface())
+        peer = self.nodes[0].add_p2p_connection(P2PInterface())
 
         self.test_dersig_info(is_active=False)
 
@@ -84,7 +84,7 @@ class BIP66Test(BitcoinTestFramework):
         block.solve()
 
         self.test_dersig_info(is_active=False)  # Not active as of current tip and next block does not need to obey rules
-        self.nodes[0].p2p.send_and_ping(msg_block(block))
+        peer.send_and_ping(msg_block(block))
         self.test_dersig_info(is_active=True)  # Not active as of current tip, but next block must obey rules
         assert_equal(self.nodes[0].getbestblockhash(), block.hash)
 
@@ -97,9 +97,9 @@ class BIP66Test(BitcoinTestFramework):
         block.solve()
 
         with self.nodes[0].assert_debug_log(expected_msgs=['{}, bad-version(0x00000002)'.format(block.hash)]):
-            self.nodes[0].p2p.send_and_ping(msg_block(block))
+            peer.send_and_ping(msg_block(block))
             assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
-            self.nodes[0].p2p.sync_with_ping()
+            peer.sync_with_ping()
 
         self.log.info("Test that transactions with non-DER signatures cannot appear in a block")
         block.nVersion = 3
@@ -123,9 +123,9 @@ class BIP66Test(BitcoinTestFramework):
         block.solve()
 
         with self.nodes[0].assert_debug_log(expected_msgs=['CheckInputScripts on {} failed with non-mandatory-script-verify-flag (Non-canonical DER signature)'.format(block.vtx[-1].hash)]):
-            self.nodes[0].p2p.send_and_ping(msg_block(block))
+            peer.send_and_ping(msg_block(block))
             assert_equal(int(self.nodes[0].getbestblockhash(), 16), tip)
-            self.nodes[0].p2p.sync_with_ping()
+            peer.sync_with_ping()
 
         self.log.info("Test that a version 3 block with a DERSIG-compliant transaction is accepted")
         block.vtx[1] = create_transaction(self.nodes[0], self.coinbase_txids[1], self.nodeaddress, amount=1.0)
@@ -134,7 +134,7 @@ class BIP66Test(BitcoinTestFramework):
         block.solve()
 
         self.test_dersig_info(is_active=True)  # Not active as of current tip, but next block must obey rules
-        self.nodes[0].p2p.send_and_ping(msg_block(block))
+        peer.send_and_ping(msg_block(block))
         self.test_dersig_info(is_active=True)  # Active as of current tip
         assert_equal(int(self.nodes[0].getbestblockhash(), 16), block.sha256)