profiling(gecko): add main_thread_id to MockInterpreter and add check in Gecko test

Signed-off-by: Sofia Donato Ferreira <flowlnlnln@gmail.com>

Author: flowln

Lib/test/test_profiling/test_sampling_profiler/mocks.py

@@ -50,12 +50,13 @@ def __repr__(self):
 class MockInterpreterInfo:
     """Mock InterpreterInfo for testing since the real one isn't accessible."""
 
-    def __init__(self, interpreter_id, threads):
+    def __init__(self, interpreter_id, threads, main_thread_id=None):
         self.interpreter_id = interpreter_id
+        self.main_thread_id = main_thread_id
         self.threads = threads
 
     def __repr__(self):
-        return f"MockInterpreterInfo(interpreter_id={self.interpreter_id}, threads={self.threads})"
+        return f"MockInterpreterInfo(interpreter_id={self.interpreter_id}, main_thread_id={self.main_thread_id}, threads={self.threads})"
 
 
 class MockCoroInfo:

Lib/test/test_profiling/test_sampling_profiler/test_collectors.py

@@ -526,6 +526,7 @@ def test_gecko_collector_basic(self):
                         [MockFrameInfo("file.py", 10, "func1"), MockFrameInfo("file.py", 20, "func2")],
                     )
                 ],
+                main_thread_id=1,
             )
         ]
         collector.collect(test_frames)
@@ -556,6 +557,7 @@ def test_gecko_collector_basic(self):
         threads = profile_data["threads"]
         self.assertEqual(len(threads), 1)
         thread_data = threads[0]
+        self.assertTrue(thread_data["isMainThread"])
 
         # Verify thread structure
         self.assertIn("samples", thread_data)