From 3e34a4cc0ce355ab0e17304808ff617470f8afbd Mon Sep 17 00:00:00 2001
From: cobalt <61329810+cobaltt7@users.noreply.github.com>
Date: Wed, 27 Nov 2024 17:41:09 -0600
Subject: [PATCH] Support sets

Signed-off-by: cobalt <61329810+cobaltt7@users.noreply.github.com>
---
 src/black/linegen.py                                  | 11 +++++++----
 .../cases/preview_remove_lone_list_item_parens.py     |  6 ++++++
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/black/linegen.py b/src/black/linegen.py
index a868c885218..7bd018d31af 100644
--- a/src/black/linegen.py
+++ b/src/black/linegen.py
@@ -512,11 +512,14 @@ def visit_atom(self, node: Node) -> Iterator[Line]:
         if (
             Preview.remove_lone_list_item_parens in self.mode
             and len(node.children) == 3
-            and node.children[0].type == token.LSQB
-            and node.children[-1].type == token.RSQB
         ):
-            # Lists of one item
-            maybe_make_parens_invisible_in_atom(node.children[1], parent=node)
+            first = node.children[0]
+            last = node.children[-1]
+            if (first.type == token.LSQB and last.type == token.RSQB) or (
+                first.type == token.LBRACE and last.type == token.RBRACE
+            ):
+                # Lists or sets of one item
+                maybe_make_parens_invisible_in_atom(node.children[1], parent=node)
 
         yield from self.visit_default(node)
 
diff --git a/tests/data/cases/preview_remove_lone_list_item_parens.py b/tests/data/cases/preview_remove_lone_list_item_parens.py
index 4b296d29ea5..ad7058ba179 100644
--- a/tests/data/cases/preview_remove_lone_list_item_parens.py
+++ b/tests/data/cases/preview_remove_lone_list_item_parens.py
@@ -5,6 +5,9 @@
 items = [(((((True,)))))]
 items = [((((()))))]
 items = [(x for x in [1])]
+items = {(123)}
+items = {(True)}
+items = {(((((True)))))}
 
 # Requires `hug_parens_with_braces_and_square_brackets` unstable style to remove parentheses
 # around multiline values
@@ -85,6 +88,9 @@
 items = [(True,)]
 items = [()]
 items = [(x for x in [1])]
+items = {123}
+items = {True}
+items = {True}
 
 # Requires `hug_parens_with_braces_and_square_brackets` unstable style to remove parentheses
 # around multiline values