llvm-type-switch-case-types

Finds llvm::TypeSwitch::Case calls with redundant explicit template arguments that can be inferred from the lambda parameter type.

This check identifies two patterns:

1. Redundant explicit type: When the lambda parameter type matches the Case template argument, the explicit type can be removed.

2. Auto parameter with explicit type: When a lambda uses auto but Case has an explicit template argument, suggests using an explicit type in the lambda instead.

Example

llvm::TypeSwitch<Base *, int>(base)
    .Case<DerivedA>([](DerivedA *a) { return 1; }) // Redundant.
    .Case<DerivedB>([](auto b) { return 2; });     // `auto` with explicit type.

Transforms to:

llvm::TypeSwitch<Base *, int>(base)
    .Case([](DerivedA *a) { return 1; })       // Type inferred from lambda.
    .Case<DerivedB>([](auto b) { return 2; }); // Warning only.

Note: The second case (auto parameter) only emits a warning without a fix-it, because the deduced type of auto depends on dyn_cast behavior which varies between pointer types and MLIR handle types.