[Lldb-commits] [lldb] Detect against invalid variant index for LibStdC++ std::variant data formatters (PR #69253)

[Jordan Rupprecht via lldb-commits]

rupprecht wrote:

This seems to cause `TestTemplatePackArgs.py` to fail, e.g. https://lab.llvm.org/buildbot/#/builders/68/builds/61819

```shell
  File "/home/worker/2.0.1/lldb-x86_64-debian/llvm-project/lldb/test/API/lang/cpp/class-template-parameter-pack/TestTemplatePackArgs.py", line 42, in test_template_argument_pack
    self.assertEqual(nested_template.GetTemplateArgumentType(2).GetName(), "bool")
AssertionError: '' != 'bool'
```

https://github.com/llvm/llvm-project/pull/69253