[pegasus] Faster tokenizer tests (#7672)

src/transformers/testing_utils.py

@@ -184,13 +184,23 @@ def require_faiss(test_case):
         return test_case
 
 
-def get_tests_dir():
+def get_tests_dir(append_path=None):
     """
-    returns the full path to the `tests` dir, so that the tests can be invoked from anywhere
+    Args:
+        append_path: optional path to append to the tests dir path
+
+    Return:
+        The full path to the `tests` dir, so that the tests can be invoked from anywhere.
+        Optionally `append_path` is joined after the `tests` dir the former is provided.
+
     """
     # this function caller's __file__
     caller__file__ = inspect.stack()[1][1]
-    return os.path.abspath(os.path.dirname(caller__file__))
+    tests_dir = os.path.abspath(os.path.dirname(caller__file__))
+    if append_path:
+        return os.path.join(tests_dir, append_path)
+    else:
+        return tests_dir
 
 
 #