Summary
lint ignores context of match slice.len()
Lint Name
missing_asserts_for_indexing
Reproducer
I tried this code:
// supported: &[u8] is a function parameter, value from enum variant or provided in any other way
// to compile this code u8 can be replaced with anything implementing Display, or Debug (in that case add `:?` to format string)
match supported.len() {
0 => {}
1 => println!("{}", supported[0]),
_ => println!("{} or {}", supported[0], supported[1]),
}I saw this happen:
supported[0]
supported[0], supported[1]
indexing into a slice multiple times without an `assert`
I expected to see this happen:
as `usize is not negative and value 0 was explicitly checked, lint should never fire.
Version
rustc 1.96.0 (ac68faa20 2026-05-25)
binary: rustc
commit-hash: ac68faa20c58cbccd01ee7208bf3b6e93a7d7f96
commit-date: 2026-05-25
host: aarch64-apple-darwin
release: 1.96.0
LLVM version: 22.1.2
Additional Labels
No response
Summary
lint ignores context of
match slice.len()Lint Name
missing_asserts_for_indexing
Reproducer
I tried this code:
I saw this happen:
I expected to see this happen:
as `usize is not negative and value 0 was explicitly checked, lint should never fire.
Version
Additional Labels
No response