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> RonnyPfannschmidt 
>
>practically this belongs to the FunctionDefininition (and should only happen once at that) 
>unfortunately with the current design that's not exposed and we have a hack instead
>
>the ""correct" fix is not to have more than one place where this is added, but that's for after FunctionDefinition lands

Co-Authored-By: Ronny Pfannschmidt <opensource@ronnypfannschmidt.de>

src/_pytest/debugging.py

@@ -279,7 +279,8 @@ def _test_pytest_function(pyfuncitem):
         raise ValueError("--trace can't be used with a fixture named func!")
     pyfuncitem.funcargs["func"] = testfunction
     if "func" not in pyfuncitem._fixtureinfo.argnames:
-        # if using e.g. parametrize the _fixtureinfo is shared
+        # TODO: when using parameterized tests, the _fixtureinfo is shared
+        # that needs to move to FunctionDefinition
         new_list = list(pyfuncitem._fixtureinfo.argnames)
         new_list.append("func")
         pyfuncitem._fixtureinfo.argnames = tuple(new_list)

testing/test_pdb.py

@@ -1025,7 +1025,7 @@ def test_3():
         assert "Exit: Quitting debugger" not in child.before.decode("utf8")
         TestPDB.flush(child)
 
-    def test_trace_with_parametrize(self, testdir):
+    def test_trace_with_parametrize_handles_shared_fixtureinfo(self, testdir):
         p1 = testdir.makepyfile(
             """
             import pytest