PY-86308: Fix profiler module execution with -m flag

Problem:
- Profiling with -m flag failed to find modules in Python 3.12+
- pkgutil.get_loader() was deprecated in Python 3.3 and removed in Python 3.12
- Module arguments (e.g., -e, --mode) were incorrectly parsed as profiler arguments

Solution:
1. Updated get_fullname() in prof_util.py:
   - Use importlib.util.find_spec() for Python 3.x (modern API)
   - Keep pkgutil.get_loader() only for Python 2.7 (legacy support)

2. Fixed argument parsing in run_profiler.py:
   - When -m is specified, all remaining args are passed to the target module
   - Avoid double-parsing that caused "unrecognized arguments" errors

Space-RevId: 86889a34e12bd9cdc510eb5fce739ce96e870789

GitOrigin-RevId: f9b609ff9a36ad6ec02476507892e2b263322930

python/helpers/profiler/prof_util.py

@@ -45,15 +45,27 @@ def save_main_module(file, module_name):
 
 
 def get_fullname(mod_name):
+    # Use pkgutil ONLY for Python 2.7 (legacy support)
+    if sys.version_info[:2] == (2, 7):
+        try:
+            loader = pkgutil.get_loader(mod_name)
+        except (ImportError, AttributeError, TypeError, ValueError):
+            return None
+        if loader is not None:
+            for attr in ("get_filename", "_get_filename"):
+                meth = getattr(loader, attr, None)
+                if meth is not None:
+                    return meth(mod_name)
+        return None
+    
+    # Use modern importlib API for all other Python versions (3.x)
     try:
-        loader = pkgutil.get_loader(mod_name)
-    except:
+        import importlib.util
+        spec = importlib.util.find_spec(mod_name)
+        if spec is not None and spec.origin is not None:
+            return spec.origin
+    except (ImportError, AttributeError, TypeError, ValueError, ModuleNotFoundError):
         return None
-    if loader is not None:
-        for attr in ("get_filename", "_get_filename"):
-            meth = getattr(loader, attr, None)
-            if meth is not None:
-                return meth(mod_name)
     return None
 
 

python/helpers/profiler/run_profiler.py

@@ -1,15 +1,16 @@
+import argparse
 import os
 import sys
 import time
 import traceback
-import argparse
 from socket import AF_INET
 from socket import SOCK_STREAM
 from socket import socket
 
 from _prof_imports import ProfilerResponse
 from prof_io import ProfWriter, ProfReader
-from prof_util import generate_snapshot_filepath, stats_to_response, get_snapshot_basepath, save_main_module, execfile, get_fullname
+from prof_util import generate_snapshot_filepath, stats_to_response, \
+    get_snapshot_basepath, save_main_module, execfile, get_fullname
 
 base_snapshot_path = os.getenv('PYCHARM_SNAPSHOT_PATH')
 remote_run = bool(os.getenv('PYCHARM_REMOTE_RUN', ''))
@@ -170,17 +171,20 @@ def parse_arguments():
 
     args, remaining_args = parser.parse_known_args()
 
+    if args.module:
+        # When -m is specified, all remaining args go to the module
+        args.file = None
+        return args, remaining_args
+
+    # When -m is not specified, parse file and its arguments
     remaining_parser = argparse.ArgumentParser(add_help=False)
     remaining_parser.add_argument('file', nargs='?', help='Python file to profile')
     remaining_parser.add_argument('args', nargs=argparse.REMAINDER, help='Arguments to pass to the target')
 
     remaining_namespace = remaining_parser.parse_args(remaining_args)
 
-    if not args.module and remaining_args:
-        args.file = remaining_namespace.file
-        remaining_args = remaining_namespace.args
-    else:
-        args.file = None
+    args.file = remaining_namespace.file
+    remaining_args = remaining_namespace.args
 
     return args, remaining_args