Merge #21254: test: Avoid connecting to real network when running tests

fa730e915766b012ff145e3c2af782668defb21f test: Avoid connecting to real network when running tests (MarcoFalke)
fa1b713941f71b077da07e9dedb743c7e99c3ca8 test: Assume node is running in subtests (MarcoFalke)

Pull request description:

  Introduced in #19884

ACKs for top commit:
  Sjors:
    ACK fa730e915766b012ff145e3c2af782668defb21f

Tree-SHA512: fe132a9ffe2fae1ab16857a3dec9839526fdf74d27a1ae794fbffca8356f639c4b916dc888b260281e9cc793916706c18d1687ebb5a076d4e1c481d218d308d3

2 files changed, 30 insertions, 22 deletions

diff --git a/test/functional/feature_config_args.py b/test/functional/feature_config_args.py
index 573760a8cb..a0bcd9f12a 100755
--- a/test/functional/feature_config_args.py
+++ b/test/functional/feature_config_args.py
@@ -19,7 +19,7 @@ class ConfArgsTest(BitcoinTestFramework):
         self.wallet_names = []
 
     def test_config_file_parser(self):
-        # Assume node is stopped
+        self.stop_node(0)
 
         inc_conf_file_path = os.path.join(self.nodes[0].datadir, 'include.conf')
         with open(os.path.join(self.nodes[0].datadir, 'bitcoin.conf'), 'a', encoding='utf-8') as conf:
@@ -89,11 +89,12 @@ class ConfArgsTest(BitcoinTestFramework):
         )
 
     def test_log_buffer(self):
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['Warning: parsed potentially confusing double-negative -connect=0\n']):
             self.start_node(0, extra_args=['-noconnect=0'])
-        self.stop_node(0)
 
     def test_args_log(self):
+        self.stop_node(0)
         self.log.info('Test config args logging')
         with self.nodes[0].assert_debug_log(
                 expected_msgs=[
@@ -120,37 +121,41 @@ class ConfArgsTest(BitcoinTestFramework):
                 '-rpcuser=secret-rpcuser',
                 '-torpassword=secret-torpassword',
             ])
-        self.stop_node(0)
 
     def test_networkactive(self):
         self.log.info('Test -networkactive option')
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['SetNetworkActive: true\n']):
             self.start_node(0)
-        self.stop_node(0)
 
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['SetNetworkActive: true\n']):
             self.start_node(0, extra_args=['-networkactive'])
-        self.stop_node(0)
 
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['SetNetworkActive: true\n']):
             self.start_node(0, extra_args=['-networkactive=1'])
-        self.stop_node(0)
 
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['SetNetworkActive: false\n']):
             self.start_node(0, extra_args=['-networkactive=0'])
-        self.stop_node(0)
 
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['SetNetworkActive: false\n']):
             self.start_node(0, extra_args=['-nonetworkactive'])
-        self.stop_node(0)
 
+        self.stop_node(0)
         with self.nodes[0].assert_debug_log(expected_msgs=['SetNetworkActive: false\n']):
             self.start_node(0, extra_args=['-nonetworkactive=1'])
-        self.stop_node(0)
 
     def test_seed_peers(self):
         self.log.info('Test seed peers')
         default_data_dir = self.nodes[0].datadir
+        # Only regtest has no fixed seeds. To avoid connections to random
+        # nodes, regtest is the only network where it is safe to enable
+        # -fixedseeds in tests
+        util.assert_equal(self.nodes[0].getblockchaininfo()['chain'],'regtest')
+        self.stop_node(0)
 
         # No peers.dat exists and -dnsseed=1
         # We expect the node will use DNS Seeds, but Regtest mode has 0 DNS seeds
@@ -159,10 +164,12 @@ class ConfArgsTest(BitcoinTestFramework):
         start = int(time.time())
         with self.nodes[0].assert_debug_log(expected_msgs=[
                 "Loaded 0 addresses from peers.dat",
-                "0 addresses found from DNS seeds"]):
-            self.start_node(0, extra_args=['-dnsseed=1 -mocktime={}'.format(start)])
+                "0 addresses found from DNS seeds",
+        ]):
+            self.start_node(0, extra_args=['-dnsseed=1', '-fixedseeds=1', f'-mocktime={start}'])
         with self.nodes[0].assert_debug_log(expected_msgs=[
-                "Adding fixed seeds as 60 seconds have passed and addrman is empty"]):
+                "Adding fixed seeds as 60 seconds have passed and addrman is empty",
+        ]):
             self.nodes[0].setmocktime(start + 65)
         self.stop_node(0)
 
@@ -173,8 +180,9 @@ class ConfArgsTest(BitcoinTestFramework):
         with self.nodes[0].assert_debug_log(expected_msgs=[
                 "Loaded 0 addresses from peers.dat",
                 "DNS seeding disabled",
-                "Adding fixed seeds as -dnsseed=0, -addnode is not provided and all -seednode(s) attempted\n"]):
-            self.start_node(0, extra_args=['-dnsseed=0'])
+                "Adding fixed seeds as -dnsseed=0, -addnode is not provided and all -seednode(s) attempted\n",
+        ]):
+            self.start_node(0, extra_args=['-dnsseed=0', '-fixedseeds=1'])
         assert time.time() - start < 60
         self.stop_node(0)
 
@@ -185,7 +193,8 @@ class ConfArgsTest(BitcoinTestFramework):
         with self.nodes[0].assert_debug_log(expected_msgs=[
                 "Loaded 0 addresses from peers.dat",
                 "DNS seeding disabled",
-                "Fixed seeds are disabled"]):
+                "Fixed seeds are disabled",
+        ]):
             self.start_node(0, extra_args=['-dnsseed=0', '-fixedseeds=0'])
         assert time.time() - start < 60
         self.stop_node(0)
@@ -196,17 +205,15 @@ class ConfArgsTest(BitcoinTestFramework):
         start = int(time.time())
         with self.nodes[0].assert_debug_log(expected_msgs=[
                 "Loaded 0 addresses from peers.dat",
-                "DNS seeding disabled"]):
-            self.start_node(0, extra_args=['-dnsseed=0', '-addnode=fakenodeaddr -mocktime={}'.format(start)])
+                "DNS seeding disabled",
+        ]):
+            self.start_node(0, extra_args=['-dnsseed=0', '-fixedseeds=1', '-addnode=fakenodeaddr', f'-mocktime={start}'])
         with self.nodes[0].assert_debug_log(expected_msgs=[
-                "Adding fixed seeds as 60 seconds have passed and addrman is empty"]):
+                "Adding fixed seeds as 60 seconds have passed and addrman is empty",
+        ]):
             self.nodes[0].setmocktime(start + 65)
-        self.stop_node(0)
-
 
     def run_test(self):
-        self.stop_node(0)
-
         self.test_log_buffer()
         self.test_args_log()
         self.test_seed_peers()
diff --git a/test/functional/test_framework/util.py b/test/functional/test_framework/util.py
index 123c48852c..d335d4ea79 100644
--- a/test/functional/test_framework/util.py
+++ b/test/functional/test_framework/util.py
@@ -368,6 +368,7 @@ def write_config(config_path, *, n, chain, extra_config=""):
         f.write("keypool=1\n")
         f.write("discover=0\n")
         f.write("dnsseed=0\n")
+        f.write("fixedseeds=0\n")
         f.write("listenonion=0\n")
         f.write("printtoconsole=0\n")
         f.write("upnp=0\n")