test(profiling): increase verbosity and assert debug data (#4174)

Sometimes test are flaky and it's hard to debug them when they are not
reproducible.

This increases the verbosity of reports for pytest so it prints more data when
test fails.

This also adds details about a flaky test in test_asyncio that failed at least
once for unknown reason on Windows.

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

Author: jd

tests/profiling/collector/test_stack_asyncio.py

@@ -51,7 +51,8 @@ async def hello() -> None:
     t2_name = _asyncio._task_get_name(t2)
 
     cpu_time_found = False
-    for event in events[stack_event.StackSampleEvent]:
+    stack_sample_events = events[stack_event.StackSampleEvent]
+    for event in stack_sample_events:
 
         wall_time_ns[event.task_name] += event.wall_time_ns
 
@@ -87,7 +88,7 @@ async def hello() -> None:
 
     if _asyncio_compat.PY38_AND_LATER:
         # We don't know the name of this task for Python < 3.8
-        assert wall_time_ns["main"] > 0
+        assert wall_time_ns["main"] > 0, (wall_time_ns, stack_sample_events)
 
     assert wall_time_ns[t1_name] > 0
     assert wall_time_ns[t2_name] > 0

tox.ini

@@ -236,9 +236,9 @@ passenv=
 commands =
 # run only essential tests related to the tracing client
     tracer: python -m pytest {posargs} tests/tracer
-    py27-profile: python -m tests.profiling.run pytest --capture=no --verbose --benchmark-disable --ignore-glob="*asyncio*" {posargs} tests/profiling
+    py27-profile: python -m tests.profiling.run pytest --capture=no --verbosity=2 --benchmark-disable --ignore-glob="*asyncio*" {posargs} tests/profiling
     # Coverage is excluded from profile because of an issue with Python 3.5.
-    py3{5,6,7,8,9,10}-profile: python -m tests.profiling.run pytest --no-cov --capture=no --verbose --benchmark-disable {posargs} tests/profiling
+    py3{5,6,7,8,9,10}-profile: python -m tests.profiling.run pytest --no-cov --capture=no --verbosity=2 --benchmark-disable {posargs} tests/profiling
 # run only the opentrace tests
     opentracer: python -m pytest {posargs} tests/opentracer/core
     opentracer_asyncio: python -m pytest {posargs} tests/opentracer/test_tracer_asyncio.py