Fix internal magic commas not being force expanded

src/black/linegen.py

@@ -1804,7 +1804,6 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[set[Leaf
                 omit.add(id(closing_bracket))
                 omit.update(inner_brackets)
                 inner_brackets.clear()
-                yield omit
 
             if (
                 prev
@@ -1819,6 +1818,7 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[set[Leaf
             if leaf.value:
                 opening_bracket = leaf.opening_bracket
                 closing_bracket = leaf
+    yield omit
 
 
 def run_transformer(

tests/data/simple_cases/deep_trailing_commas.py

@@ -0,0 +1,33 @@
+assert foo(1, 2, 3,)[0] == {"bar": "baz"}
+
+a = [1,][2]()
+b = [1,][2](3)
+
+[1, 2,]()(3, 4,)()(5, 6,)(0)(0)
+
+# output
+
+
+assert foo(
+    1,
+    2,
+    3,
+)[0] == {"bar": "baz"}
+
+a = [
+    1,
+][2]()
+b = [
+    1,
+][2](3)
+
+[
+    1,
+    2,
+]()(
+    3,
+    4,
+)()(
+    5,
+    6,
+)(0)(0)