Merge pull request pyutils#356 from TTsangSC/sys_mon_event_fix

FIX: missing line events for `raise` statements and `finally: ...` bodies in Python 3.12+

Author: Erotemic

line_profiler/_line_profiler.pyx

@@ -191,7 +191,9 @@ if CAN_USE_SYS_MONITORING:
         events = (mon.get_events(mon.PROFILER_ID)
                   | mon.events.LINE
                   | mon.events.PY_RETURN
-                  | mon.events.PY_YIELD)
+                  | mon.events.PY_YIELD
+                  | mon.events.RAISE
+                  | mon.events.RERAISE)
         mon.set_events(mon.PROFILER_ID, events)
         # TODO: store and/or call previous callbacks, see #334
         line_callback = functools.partial(
@@ -203,6 +205,10 @@ if CAN_USE_SYS_MONITORING:
             mon.PROFILER_ID, mon.events.PY_RETURN, exit_callback)
         mon.register_callback(
             mon.PROFILER_ID, mon.events.PY_YIELD, exit_callback)
+        mon.register_callback(
+            mon.PROFILER_ID, mon.events.RAISE, exit_callback)
+        mon.register_callback(
+            mon.PROFILER_ID, mon.events.RERAISE, exit_callback)
 
     def _sys_monitoring_deregister() -> None:
         if not _is_main_thread():
@@ -212,6 +218,8 @@ if CAN_USE_SYS_MONITORING:
         mon.register_callback(mon.PROFILER_ID, mon.events.LINE, None)
         mon.register_callback(mon.PROFILER_ID, mon.events.PY_RETURN, None)
         mon.register_callback(mon.PROFILER_ID, mon.events.PY_YIELD, None)
+        mon.register_callback(mon.PROFILER_ID, mon.events.RAISE, None)
+        mon.register_callback(mon.PROFILER_ID, mon.events.RERAISE, None)
 
 
 def label(code):

tests/test_line_profiler.py

@@ -1026,3 +1026,65 @@ def func(n):
         loop_body = next(line for line in result.splitlines()
                          if line.endswith('x += n'))
         assert loop_body.split()[1] == str(count)
+
+
+@pytest.mark.xfail(condition=sys.version_info[:2] == (3, 9),
+                   reason='Handling of `finally` bugged in Python 3.9')
+def test_profiling_exception():
+    """
+    Test that profiling data is reported for:
+    - The line raising an exception
+    - The last lines in the `except` and `finally` subblocks of a
+      `try`-(`except`-)`finally` statement
+
+    Notes
+    -----
+    Seems to be bugged for Python 3.9 only; may be related to CPython
+    issue #83295.
+    """
+    prof = LineProfiler()
+
+    class MyException(Exception):
+        pass
+
+    @prof
+    def func_raise():
+        pass
+        raise MyException  # Raise: raise
+        l.append(0)
+
+    @prof
+    def func_try_finally():
+        try:
+            raise MyException  # Try-finally: try
+        finally:
+            l.append(1)  # Try-finally: finally
+
+    @prof
+    def func_try_except_finally(reraise):
+        try:
+            raise MyException  # Try-except-finally: try
+        except MyException:
+            l.append(2)  # Try-except-finally: except
+            if reraise:
+                raise
+        finally:
+            l.append(3)  # Try-except-finally: finally
+
+    l = []
+    for func in [func_raise, func_try_finally,
+                 functools.partial(func_try_except_finally, True),
+                 functools.partial(func_try_except_finally, False)]:
+        try:
+            func()
+        except MyException:
+            pass
+    result = get_prof_stats(prof)
+    assert l == [1, 2, 3, 2, 3]
+    for stmt, nhits in [
+            ('raise', 1), ('try-finally', 1), ('try-except-finally', 2)]:
+        for step in stmt.split('-'):
+            comment = '# {}: {}'.format(stmt.capitalize(), step)
+            line = next(line for line in result.splitlines()
+                        if line.endswith(comment))
+            assert line.split()[1] == str(nhits)