Merge bitcoin/bitcoin#24192: test: Fix feature_init intermittent issues

fa7b07571f24b6def6effdd4cc1b96c7507bf959 test: Fix feature_init intermittent issues (MarcoFalke)
fa4595deb334f14dac9ba481d786a823e0f0fde1 test: Remove random line number feature from feature_init.py (MarcoFalke)

Pull request description:

  The test doesn't work currently because the log might be finalized before `wait_for_debug_log` is started, in which case it will assume the log is empty and fail to detect any line.

  Fix this by calling `wait_for_debug_log` first. Fixes #24060.

  Also, remove the "random line number" part of the test, because it doesn't really test anything novel. `wait_for_debug_log` is inherently racy, so will randomly terminate at the exact point or later. So the randomization is already sufficiently covered.

ACKs for top commit:
  jamesob:
    ACK https://github.com/bitcoin/bitcoin/pull/24192/commits/fa7b07571f24b6def6effdd4cc1b96c7507bf959
  mzumsande:
    Code Review ACK fa7b07571f24b6def6effdd4cc1b96c7507bf959

Tree-SHA512: f107a04926270a1d9ac8f53b6e5254566d1827ba7d27fd74f9ce909319f8794f8bd46da9c42256bf41b6df26c0bad8b9a0d54e4e148695189af09f31e3948330

1 files changed, 5 insertions, 4 deletions

diff --git a/test/functional/test_framework/test_node.py b/test/functional/test_framework/test_node.py
index 0b9154a030..289e83579b 100755
--- a/test/functional/test_framework/test_node.py
+++ b/test/functional/test_framework/test_node.py
@@ -422,7 +422,8 @@ class TestNode():
             time.sleep(0.05)
         self._raise_assertion_error('Expected messages "{}" does not partially match log:\n\n{}\n\n'.format(str(expected_msgs), print_log))
 
-    def wait_for_debug_log(self, expected_msgs, timeout=10, ignore_case=False) -> int:
+    @contextlib.contextmanager
+    def wait_for_debug_log(self, expected_msgs, timeout=60, ignore_case=False):
         """
         Block until we see a particular debug log message fragment or until we exceed the timeout.
         Return:
@@ -432,6 +433,8 @@ class TestNode():
         prev_size = self.debug_log_bytes()
         re_flags = re.MULTILINE | (re.IGNORECASE if ignore_case else 0)
 
+        yield
+
         while True:
             found = True
             with open(self.debug_log_path, encoding='utf-8') as dl:
@@ -443,8 +446,7 @@ class TestNode():
                     found = False
 
             if found:
-                num_logs = len(log.splitlines())
-                return num_logs
+                return
 
             if time.time() >= time_end:
                 print_log = " - " + "\n - ".join(log.splitlines())
@@ -456,7 +458,6 @@ class TestNode():
         self._raise_assertion_error(
             'Expected messages "{}" does not partially match log:\n\n{}\n\n'.format(
                 str(expected_msgs), print_log))
-        return -1  # useless return to satisfy linter
 
     @contextlib.contextmanager
     def profile_with_perf(self, profile_name: str):