The language is full of gotchas like that, you're expected to use the tooling to guardrail yourself, because having a proper type system or coherent syntax is "too complicated" (while learning dozens of patterns and weird tricks apparently isn't).

go vet and this massive collection of linters bundled into a single binary are very popular: https://golangci-lint.run

linters will warn you of accidental shadowing, among many other things.