[clang-tools-extra] readability-identifier-naming should add universal default options (PR #171686)

[Baranov Victor via cfe-commits]

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@@ -1571,8 +1577,14 @@ StyleKind IdentifierNamingCheck::findStyleKindForVar(
   if (NamingStyles[SK_Variable])
     return SK_Variable;
 
-  return SK_Invalid;
+  return undefinedStyle(NamingStyles);
+}
+
+StyleKind IdentifierNamingCheck::undefinedStyle(
+    ArrayRef<std::optional<NamingStyle>> NamingStyles) const {
+  return NamingStyles[SK_Default] ? SK_Default : SK_Invalid;
 }
 
 } // namespace readability
 } // namespace clang::tidy
+
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vbvictor wrote:

Same unrelated?

https://github.com/llvm/llvm-project/pull/171686