[clang-tools-extra] [clang-tidy] Fix readability-identifier-naming FP with DefaultCase on function templates (PR #189788)

[via cfe-commits]

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@@ -422,6 +422,11 @@ Changes in existing checks
   now uses separate note diagnostics for each uninitialized enumerator, making
   it easier to see which specific enumerators need explicit initialization.
 
+- Improved :doc:`readability-identifier-naming
+  <clang-tidy/checks/readability/identifier-naming>` check by fixing a false
+  positive where function templates could be diagnosed as generic identifiers
+  when ``DefaultCase`` was enabled.
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EugeneZelenko wrote:

```suggestion
  when `DefaultCase` was enabled.
```

https://github.com/llvm/llvm-project/pull/189788