[renanmpimentel]

Why this test matters

Treating an excluded start bound as inclusive would return ell instead of ll for the demonstrated slice. The new test protects RangeBounds semantics that the previous suite did not exercise.

Supertest audit method

I used the Supertest test-audit skill to probe whether the existing suite would catch a plausible violation of this contract. The regression was applied only in an isolated worktree. The regression proof records three executed states: the existing tests pass with that regression, the new assertion fails against the same regression, and the new test passes with the original production code restored. The published diff adds tests only.

Change and verification

Adds a Bytes::slice regression case using an excluded start bound. For b"hello", (Excluded(1), Excluded(4)) must produce b"ll".

Regression proof: treating an excluded start as inclusive leaves the existing all-feature integration suite passing, but this case fails with b"ell". With production code restored, cargo test --all-features passes, including 248 doctests. cargo fmt --check and cargo check --no-default-features also pass.

Clippy was run on all-feature tests with -A clippy::reversed_empty_ranges because an existing out-of-range test intentionally uses 5..3; the remaining pre-existing warnings do not fail the run. This PR changes tests only.

Repository guidance

No contribution guide or PR template was present in the audited checkout. The all-feature tests, formatting and check passed; Clippy needed the documented allowance for an existing intentionally reversed range.