[clang-tools-extra] issue-63565: community requested small QoL fix for more configurabili… (PR #108005)

[Nathan Ridge via cfe-commits]

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@@ -126,11 +126,29 @@ struct Config {
     std::vector<std::string> FullyQualifiedNamespaces;
   } Style;
 
+  /// controls the completion options for argument lists.
+  enum class ArgumentListsOption {
+    /// the default value. This will imply FullPlaceholders unless overridden by
+    /// --function-arg-placeholders=0, in which case Delimiters is used.
+    /// any other use-case of --function-arg-placeholders is ignored
+    UnsetDefault = 0,
+    /// nothing, no argument list and also NO Delimiters "()" or "<>"
+    None,
+    /// open, only opening delimiter "(" or "<"
+    OpenDelimiter,
+    /// empty pair of delimiters "()" or "<>" (or [legacy] alias 0)
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HighCommander4 wrote:

nit: these mentions of legacy aliases can be removed (it's just confusing since that applies to the command line flag which is defined elsewhere)

https://github.com/llvm/llvm-project/pull/108005