diff --git a/mlir/test/python/dialects/ext_test_helper.py b/mlir/test/python/dialects/ext_test_helper.py
new file mode 100644
--- /dev/null
+++ b/mlir/test/python/dialects/ext_test_helper.py
@@ -0,0 +1,23 @@
+import inspect
+
+
+def print_gen_init_arg_names(cls: type):
+    """
+    Prints the argument names of the __init__ function of the generated base
+    class of a mix-in extension.
+
+    This is useful for ensuring that mix-in classes remain in sync with their
+    underlying op. If operands are added or existing ones are renamed in that
+    op, the same change needs to occur in the mix-in class. However, in many
+    cases, these changes do not otherwise break the tests of the mix-ins, such
+    that the mix-in classes become out of sync. This function allows to print
+    the argument names of the generated base class, which can then be checked
+    for in a `CHECK` statement.
+
+    If you are modifying a tablegen definition and that modification breaks a
+    test that uses this function, please update the corresponding mix-in class
+    in the `*_ext.py` of the dialect.
+    """
+    mro = cls.__mro__[2]
+    assert mro.__module__.endswith("_gen")
+    print(list(inspect.signature(mro.__init__).parameters.keys()))
diff --git a/mlir/test/python/dialects/transform_gpu_ext.py b/mlir/test/python/dialects/transform_gpu_ext.py
--- a/mlir/test/python/dialects/transform_gpu_ext.py
+++ b/mlir/test/python/dialects/transform_gpu_ext.py
@@ -4,8 +4,11 @@
 from mlir.dialects import transform
 from mlir.dialects.transform import gpu
 
+from ext_test_helper import print_gen_init_arg_names
+
 
 def run(f):
+    print("\nTEST:", f.__name__)
     with Context(), Location.unknown():
         module = Module.create()
         with InsertionPoint(module.body):
@@ -17,7 +20,6 @@
             with InsertionPoint(sequence.body):
                 f(sequence.bodyTarget)
                 transform.YieldOp()
-        print("\nTEST:", f.__name__)
         print(module)
     return f
 
@@ -77,3 +79,10 @@
     # CHECK-SAME: block_dims = [4, 2]
     # CHECK-SAME: sync_after_distribute = false
     # CHECK-SAME: warp_size = 64
+
+
+@run
+def testMapNestedForallToThreadsGenArgs(_):
+    print_gen_init_arg_names(gpu.MapNestedForallToThreads)
+    # CHECK-LABEL: TEST: testMapNestedForallToThreadsGenArgs
+    # CHECK: ['self', 'result', 'target', 'block_dims', 'sync_after_distribute', 'warp_size', 'loc', 'ip']