[Tests] Add is flaky decorator (#5139)

* add is flaky decorator

* fix more

src/diffusers/utils/testing_utils.py

@@ -1,3 +1,4 @@
+import functools
 import importlib
 import inspect
 import io
@@ -7,7 +8,9 @@
 import random
 import re
 import struct
+import sys
 import tempfile
+import time
 import unittest
 import urllib.parse
 from contextlib import contextmanager
@@ -612,6 +615,43 @@ def summary_failures_short(tr):
     config.option.tbstyle = orig_tbstyle
 
 
+# Copied from https://github.com/huggingface/transformers/blob/000e52aec8850d3fe2f360adc6fd256e5b47fe4c/src/transformers/testing_utils.py#L1905
+def is_flaky(max_attempts: int = 5, wait_before_retry: Optional[float] = None, description: Optional[str] = None):
+    """
+    To decorate flaky tests. They will be retried on failures.
+
+    Args:
+        max_attempts (`int`, *optional*, defaults to 5):
+            The maximum number of attempts to retry the flaky test.
+        wait_before_retry (`float`, *optional*):
+            If provided, will wait that number of seconds before retrying the test.
+        description (`str`, *optional*):
+            A string to describe the situation (what / where / why is flaky, link to GH issue/PR comments, errors,
+            etc.)
+    """
+
+    def decorator(test_func_ref):
+        @functools.wraps(test_func_ref)
+        def wrapper(*args, **kwargs):
+            retry_count = 1
+
+            while retry_count < max_attempts:
+                try:
+                    return test_func_ref(*args, **kwargs)
+
+                except Exception as err:
+                    print(f"Test failed with {err} at try {retry_count}/{max_attempts}.", file=sys.stderr)
+                    if wait_before_retry is not None:
+                        time.sleep(wait_before_retry)
+                    retry_count += 1
+
+            return test_func_ref(*args, **kwargs)
+
+        return wrapper
+
+    return decorator
+
+
 # Taken from: https://github.com/huggingface/transformers/blob/3658488ff77ff8d45101293e749263acf437f4d5/src/transformers/testing_utils.py#L1787
 def run_test_in_subprocess(test_case, target_func, inputs=None, timeout=None):
     """

tests/pipelines/text_to_video/test_video_to_video.py

@@ -30,6 +30,7 @@
 from diffusers.utils.testing_utils import (
     enable_full_determinism,
     floats_tensor,
+    is_flaky,
     skip_mps,
     slow,
     torch_device,
@@ -156,9 +157,14 @@ def test_text_to_video_default_case(self):
 
         assert np.abs(image_slice.flatten() - expected_slice).max() < 1e-2
 
+    @is_flaky()
     def test_save_load_optional_components(self):
         super().test_save_load_optional_components(expected_max_difference=0.001)
 
+    @is_flaky()
+    def test_dict_tuple_outputs_equivalent(self):
+        super().test_dict_tuple_outputs_equivalent()
+
     @unittest.skipIf(
         torch_device != "cuda" or not is_xformers_available(),
         reason="XFormers attention is only available with CUDA and `xformers` installed",