[clang] [clang-format] add BinPackLongBracedLists style option (PR #112482)

[Owen Pan via cfe-commits]

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@@ -1212,6 +1212,22 @@ struct FormatStyle {
   /// \version 3.7
   bool BinPackArguments;
 
+  /// If ``BinPackLongBracedLists`` is ``true`` it overrides
+  /// ``BinPackArguments`` if there are 20 or more items in a braced
+  /// initializer list.
+  /// \code
+  ///    BinPackLongBracedLists: false  vs.   BinPackLongBracedLists: true
+  ///    vector<int> x{                       vector<int> x{1, 2, ...,
+  ///                                                       20, 21};
+  ///                1,
+  ///                2,
+  ///                ...,
+  ///                20,
+  ///                21};
+  /// \endcode
+  /// \version 21
+  bool BinPackLongBracedLists;
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owenca wrote:

```suggestion
  bool BinPackLongBracedList;
```

https://github.com/llvm/llvm-project/pull/112482