Harden glob compilation + property/fuzz tests; edition 2024, MSRV 1.85, release 0.2.0

[prostomarkeloff]

Harden glob compilation + property/fuzz tests; edition 2024, MSRV 1.85, release 0.2.0

TL;DR

Closes a compile-time DoS in the glob engine (a short brace "bomb" could OOM Pattern::compile), backs the engine's safety claims with proptest + cargo-fuzz, modernizes the toolchain to edition 2024 / MSRV 1.85, and cuts v0.2.0.

Why

The README promised "linear-time, no catastrophic backtracking on untrusted patterns" — but that only covered matching. Brace compilation was the gap: {a,b}{c,d}… is a cross product, so a short adversarial pattern ({a,b} ×30 — a few bytes) demanded 2³⁰ sub-patterns and blew up memory at compile time, before the linear matcher ever ran. directiva::source::file parses untrusted directive files, so this was reachable.

Separately, the declared rust-version = "1.74" was fiction: pyo3 0.28 (the python feature) already needs 1.83, and nothing verified the floor.

What changed

The fix — bounded compilation. Brace expansion now caps the running cross product at a public MAX_BRACE_ALTS (core::glob, = 1024). A pattern that would exceed it degrades to a single literal alternative (braces matched verbatim — the same leniency already applied to an unmatched brace). The check happens before allocation, so both time and memory stay O(cap · depth) on any input — never O(2ⁿ).

Property tests (proptest, a dev-dependency). Run as part of cargo test:

• parser is total (returns Result, never panics) and any Ok has a non-empty action + NAME;
• glob compile is total and bounded (alt_count ∈ [1, MAX_BRACE_ALTS]), matches never panics, metachar-free patterns are full-anchored.

Fuzzing (cargo-fuzz). A standalone fuzz/ crate (own workspace, nightly-only) with parse and glob targets; the glob target asserts the brace cap as a fuzz invariant. Excluded from the published crate. Both targets ran clean locally (~478k / ~611k execs, 0 crashes, ASan).

Toolchain. Edition 2021 → 2024; MSRV 1.74 → 1.85 (edition floor, ≥ pyo3's 1.83), now pinned by a dedicated CI job (cargo test + cargo check --features python on 1.85).

Release. Version 0.1.0 → 0.2.0 + README install references.

Testing

• cargo test — 64 tests pass (was 56: +brace-cap units, +5 proptest properties).
• cargo clippy --all-targets -- -D warnings and cargo clippy --features python -- -D warnings — clean.
• cargo fmt --check — clean.
• Verified on a real 1.85.0 toolchain: default cargo test green, cargo check --features python green.
• cargo +nightly fuzz run parse|glob — clean.

Notes

• nightly is required only to run the fuzzers (cargo-fuzz needs -Zsanitizer*); the library, tests, proptest, and clippy are all stable.
• No public API removed; MAX_BRACE_ALTS is the one new public item.