Move wrap_long_dict_values_in_parens to the preview style (#4561)

Author: cobaltt7

Diff for: CHANGES.md

@@ -43,6 +43,7 @@ The following changes were not in any previous release:
 - Collapse multiple empty lines after an import into one (#4489)
 - Prevent `string_processing` and `wrap_long_dict_values_in_parens` from removing
   parentheses around long dictionary values (#4377)
+- Move `wrap_long_dict_values_in_parens` from the unstable to preview style (#4561)
 
 ### Configuration
 

Diff for: docs/the_black_code_style/future_style.md

@@ -22,20 +22,47 @@ Currently, the following features are included in the preview style:
 
 - `always_one_newline_after_import`: Always force one blank line after import
   statements, except when the line after the import is a comment or an import statement
+- `wrap_long_dict_values_in_parens`: Add parentheses around long values in dictionaries
+  ([see below](labels/wrap-long-dict-values))
 
 (labels/unstable-features)=
 
 The unstable style additionally includes the following features:
 
 - `string_processing`: split long string literals and related changes
   ([see below](labels/string-processing))
-- `wrap_long_dict_values_in_parens`: add parentheses to long values in dictionaries
-  ([see below](labels/wrap-long-dict-values))
 - `multiline_string_handling`: more compact formatting of expressions involving
   multiline strings ([see below](labels/multiline-string-handling))
 - `hug_parens_with_braces_and_square_brackets`: more compact formatting of nested
   brackets ([see below](labels/hug-parens))
 
+(labels/wrap-long-dict-values)=
+
+### Improved parentheses management in dicts
+
+For dict literals with long values, they are now wrapped in parentheses. Unnecessary
+parentheses are now removed. For example:
+
+```python
+my_dict = {
+    "a key in my dict": a_very_long_variable
+    * and_a_very_long_function_call()
+    / 100000.0,
+    "another key": (short_value),
+}
+```
+
+will be changed to:
+
+```python
+my_dict = {
+    "a key in my dict": (
+        a_very_long_variable * and_a_very_long_function_call() / 100000.0
+    ),
+    "another key": short_value,
+}
+```
+
 (labels/hug-parens)=
 
 ### Improved multiline dictionary and list indentation for sole function parameter
@@ -122,33 +149,6 @@ exceed the line length limit. Line continuation backslashes are converted into
 parenthesized strings. Unnecessary parentheses are stripped. The stability and status of
 this feature istracked in [this issue](https://github.com/psf/black/issues/2188).
 
-(labels/wrap-long-dict-values)=
-
-### Improved parentheses management in dicts
-
-For dict literals with long values, they are now wrapped in parentheses. Unnecessary
-parentheses are now removed. For example:
-
-```python
-my_dict = {
-    "a key in my dict": a_very_long_variable
-    * and_a_very_long_function_call()
-    / 100000.0,
-    "another key": (short_value),
-}
-```
-
-will be changed to:
-
-```python
-my_dict = {
-    "a key in my dict": (
-        a_very_long_variable * and_a_very_long_function_call() / 100000.0
-    ),
-    "another key": short_value,
-}
-```
-
 (labels/multiline-string-handling)=
 
 ### Improved multiline string handling

Diff for: src/black/mode.py

@@ -208,8 +208,6 @@ class Preview(Enum):
 UNSTABLE_FEATURES: set[Preview] = {
     # Many issues, see summary in https://github.com/psf/black/issues/4042
     Preview.string_processing,
-    # See issues #3452 and #4158
-    Preview.wrap_long_dict_values_in_parens,
     # See issue #4159
     Preview.multiline_string_handling,
     # See issue #4036 (crash), #4098, #4099 (proposed tweaks)

Diff for: tests/data/cases/preview_long_dict_values.py

@@ -1,4 +1,4 @@
-# flags: --unstable
+# flags: --preview
 x = {
     "xx_xxxxx_xxxxxxxxxx_xxxxxxxxx_xx": (
         "xx:xxxxxxxxxxxxxxxxx_xxxxx_xxxxxxx_xxxxxxxxxxx{xx}xxx_xxxxx_xxxxxxxxx_xxxxxxxxxxxx_xxxx"
@@ -287,15 +287,17 @@ def bar():
 
 class Random:
     def func():
-        random_service.status.active_states.inactive = make_new_top_level_state_from_dict({
-            "topLevelBase": {
-                "secondaryBase": {
-                    "timestamp": 1234,
-                    "latitude": 1,
-                    "longitude": 2,
-                    "actionTimestamp": (
-                        Timestamp(seconds=1530584000, nanos=0).ToJsonString()
-                    ),
-                }
-            },
-        })
+        random_service.status.active_states.inactive = make_new_top_level_state_from_dict(
+            {
+                "topLevelBase": {
+                    "secondaryBase": {
+                        "timestamp": 1234,
+                        "latitude": 1,
+                        "longitude": 2,
+                        "actionTimestamp": (
+                            Timestamp(seconds=1530584000, nanos=0).ToJsonString()
+                        ),
+                    }
+                },
+            }
+        )

Diff for: tests/data/cases/walrus_in_dict.py

@@ -1,9 +1,9 @@
-# flags: --unstable
-# This is testing an issue that is specific to the unstable style (wrap_long_dict_values_in_parens)
+# flags: --preview
+# This is testing an issue that is specific to the preview style (wrap_long_dict_values_in_parens)
 {
     "is_update": (up := commit.hash in update_hashes)
 }
 
 # output
-# This is testing an issue that is specific to the unstable style (wrap_long_dict_values_in_parens)
+# This is testing an issue that is specific to the preview style (wrap_long_dict_values_in_parens)
 {"is_update": (up := commit.hash in update_hashes)}