diff --git a/tests/data/preview/return_annotation_brackets_string.py b/tests/data/preview/return_annotation_brackets_string.py
new file mode 100644
index 0000000..6978829
--- /dev/null
+++ b/tests/data/preview/return_annotation_brackets_string.py
@@ -0,0 +1,12 @@
+# Long string example
+def frobnicate() -> "ThisIsTrulyUnreasonablyExtremelyLongClassName | list[ThisIsTrulyUnreasonablyExtremelyLongClassName]":
+    pass
+
+# output
+
+# Long string example
+def frobnicate() -> (
+    "ThisIsTrulyUnreasonablyExtremelyLongClassName |"
+    " list[ThisIsTrulyUnreasonablyExtremelyLongClassName]"
+):
+    pass
diff --git a/tests/data/preview/comments8.py b/tests/data/simple_cases/comments8.py
similarity index 100%
rename from tests/data/preview/comments8.py
rename to tests/data/simple_cases/comments8.py
diff --git a/tests/data/preview/comments9.py b/tests/data/simple_cases/comments9.py
similarity index 100%
rename from tests/data/preview/comments9.py
rename to tests/data/simple_cases/comments9.py
diff --git a/tests/data/preview/docstring_preview.py b/tests/data/simple_cases/docstring_preview.py
similarity index 100%
rename from tests/data/preview/docstring_preview.py
rename to tests/data/simple_cases/docstring_preview.py
diff --git a/tests/data/preview/one_element_subscript.py b/tests/data/simple_cases/one_element_subscript.py
similarity index 100%
rename from tests/data/preview/one_element_subscript.py
rename to tests/data/simple_cases/one_element_subscript.py
diff --git a/tests/data/preview/prefer_rhs_split_reformatted.py b/tests/data/simple_cases/prefer_rhs_split_reformatted.py
similarity index 100%
rename from tests/data/preview/prefer_rhs_split_reformatted.py
rename to tests/data/simple_cases/prefer_rhs_split_reformatted.py
diff --git a/tests/data/preview/remove_await_parens.py b/tests/data/simple_cases/remove_await_parens.py
similarity index 100%
rename from tests/data/preview/remove_await_parens.py
rename to tests/data/simple_cases/remove_await_parens.py
diff --git a/tests/data/preview/remove_except_parens.py b/tests/data/simple_cases/remove_except_parens.py
similarity index 100%
rename from tests/data/preview/remove_except_parens.py
rename to tests/data/simple_cases/remove_except_parens.py
diff --git a/tests/data/preview/remove_for_brackets.py b/tests/data/simple_cases/remove_for_brackets.py
similarity index 100%
rename from tests/data/preview/remove_for_brackets.py
rename to tests/data/simple_cases/remove_for_brackets.py
diff --git a/tests/data/preview/remove_newline_after_code_block_open.py b/tests/data/simple_cases/remove_newline_after_code_block_open.py
similarity index 100%
rename from tests/data/preview/remove_newline_after_code_block_open.py
rename to tests/data/simple_cases/remove_newline_after_code_block_open.py
diff --git a/tests/data/preview/return_annotation_brackets.py b/tests/data/simple_cases/return_annotation_brackets.py
similarity index 93%
rename from tests/data/preview/return_annotation_brackets.py
rename to tests/data/simple_cases/return_annotation_brackets.py
index 27760bd..265c302 100644
--- a/tests/data/preview/return_annotation_brackets.py
+++ b/tests/data/simple_cases/return_annotation_brackets.py
@@ -87,10 +87,6 @@ def foo() -> tuple[loooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
 def foo() -> tuple[int, int, int,]:
     return 2
 
-# Long string example
-def frobnicate() -> "ThisIsTrulyUnreasonablyExtremelyLongClassName | list[ThisIsTrulyUnreasonablyExtremelyLongClassName]":
-    pass
-
 # output
 # Control
 def double(a: int) -> int:
@@ -212,11 +208,3 @@ def foo() -> (
     ]
 ):
     return 2
-
-
-# Long string example
-def frobnicate() -> (
-    "ThisIsTrulyUnreasonablyExtremelyLongClassName |"
-    " list[ThisIsTrulyUnreasonablyExtremelyLongClassName]"
-):
-    pass
diff --git a/tests/data/preview/skip_magic_trailing_comma.py b/tests/data/simple_cases/skip_magic_trailing_comma.py
similarity index 100%
rename from tests/data/preview/skip_magic_trailing_comma.py
rename to tests/data/simple_cases/skip_magic_trailing_comma.py
diff --git a/tests/data/preview/trailing_commas_in_leading_parts.py b/tests/data/simple_cases/trailing_commas_in_leading_parts.py
similarity index 100%
rename from tests/data/preview/trailing_commas_in_leading_parts.py
rename to tests/data/simple_cases/trailing_commas_in_leading_parts.py
diff --git a/tests/test_format.py b/tests/test_format.py
index 01cd61e..feb3cba 100644
--- a/tests/test_format.py
+++ b/tests/test_format.py
@@ -31,17 +31,15 @@ def check_file(
 @pytest.mark.filterwarnings("ignore:invalid escape sequence.*:DeprecationWarning")
 @pytest.mark.parametrize("filename", all_data_cases("simple_cases"))
 def test_simple_format(filename: str) -> None:
-    check_file("simple_cases", filename, DEFAULT_MODE)
+    magic_trailing_comma = filename != "skip_magic_trailing_comma"
+    check_file(
+        "simple_cases", filename, black.Mode(magic_trailing_comma=magic_trailing_comma)
+    )
 
 
 @pytest.mark.parametrize("filename", all_data_cases("preview"))
 def test_preview_format(filename: str) -> None:
-    magic_trailing_comma = filename != "skip_magic_trailing_comma"
-    check_file(
-        "preview",
-        filename,
-        black.Mode(preview=True, magic_trailing_comma=magic_trailing_comma),
-    )
+    check_file("preview", filename, black.Mode(preview=True))
 
 
 @pytest.mark.parametrize("filename", all_data_cases("preview_39"))