ferntree 0.6.0

name: CI

permissions:
  contents: read

on:
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

jobs:
  format:
    name: Format
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable
        with:
          components: rustfmt

      - name: Check formatting
        run: cargo fmt --all -- --check

  check:
    name: Check
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Run cargo check
        run: cargo check --all-features

  clippy:
    name: Clippy
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable
        with:
          components: clippy

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Run clippy
        run: cargo clippy --all-targets --all-features -- -D warnings

  test:
    name: Test
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Run tests
        run: cargo test --all-features --verbose

  loom:
    name: Loom
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8 # stable

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Run loom tests
        env:
          RUSTFLAGS: "--cfg loom"
        run: cargo test --features loom --release --verbose -- --test-threads=1 loom

  memory:
    name: Memory
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@5b842231ba77f5c045dba54ac5560fed2db780e2 # nightly
        with:
          components: rust-src

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Run memory tests with LeakSanitizer
        env:
          RUSTFLAGS: "-Zsanitizer=leak"
        run: cargo +nightly test --target x86_64-unknown-linux-gnu --verbose -- memory_tests

  miri:
    name: Miri
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@5b842231ba77f5c045dba54ac5560fed2db780e2 # nightly
        with:
          components: miri, rust-src

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Setup Miri
        run: cargo miri setup

      # Miri runs ~100-1000× slower than debug. We deliberately limit it to
      # `--lib` — the 226 unit tests inside the crate, which exercise every
      # unsafe code path with small deterministic data and finish in ~14
      # minutes. The `invariants.rs` integration tests (5,000-10,000 entry
      # workloads) and `unsafe_coverage.rs` concurrent scenarios push Miri
      # wall time into hours without meaningfully extending UB coverage,
      # so they are skipped here. The full integration suite still runs
      # under regular cargo test, ASan, TSan, and loom.
      #
      # `-Zmiri-tree-borrows` is required because the `crossbeam-epoch`
      # dependency has known Stacked-Borrows issues (its pinned-thread
      # list manipulation). Tree Borrows is strictly more permissive for
      # those aliasing patterns and is on track to become Rust's default
      # aliasing model. Ferntree's own unsafe code is sound under both.
      - name: Run Miri on lib unit tests
        env:
          MIRIFLAGS: "-Zmiri-tree-borrows -Zmiri-disable-isolation -Zmiri-permissive-provenance -Zmiri-ignore-leaks"
        run: cargo miri test --all-features --lib

  asan:
    name: AddressSanitizer
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@5b842231ba77f5c045dba54ac5560fed2db780e2 # nightly
        with:
          components: rust-src

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      - name: Run tests under AddressSanitizer
        env:
          RUSTFLAGS: "-Zsanitizer=address"
          RUSTDOCFLAGS: "-Zsanitizer=address"
          ASAN_OPTIONS: "detect_leaks=0:detect_stack_use_after_return=1"
        run: |
          cargo +nightly test --all-features --target x86_64-unknown-linux-gnu --verbose -- \
            --skip memory_tests

  tsan:
    name: ThreadSanitizer
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@5b842231ba77f5c045dba54ac5560fed2db780e2 # nightly
        with:
          components: rust-src

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      # TSan focuses on the concurrent test suite, which is where data races
      # would surface. Single-threaded suites are skipped to keep wall time
      # reasonable. We don't run the loom test under TSan because loom builds
      # its own scheduler.
      #
      # `-Zbuild-std` is required since recent nightly: rustc refuses to mix
      # sanitizer and non-sanitizer ABIs in the same build graph, so std and
      # all transitive deps must be rebuilt with `-Zsanitizer=thread`.
      #
      # `TSAN_OPTIONS=suppressions=...` points to a file listing known
      # false-positive race patterns inherent to optimistic lock coupling.
      # See the file for details — the algorithm's correctness under those
      # patterns is validated by the loom job, which models the full
      # version-counter handshake.
      - name: Run concurrency tests under ThreadSanitizer
        env:
          RUSTFLAGS: "-Zsanitizer=thread"
          TSAN_OPTIONS: "halt_on_error=1:second_deadlock_stack=1:suppressions=${{ github.workspace }}/.github/tsan_suppressions.txt"
        run: |
          cargo +nightly test --all-features \
            -Zbuild-std \
            --target x86_64-unknown-linux-gnu --verbose \
            --test concurrency --test deadlock_tests --test unsafe_coverage

  fuzz-smoke:
    name: Fuzz smoke test
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repository
        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4

      - name: Install Rust toolchain
        uses: dtolnay/rust-toolchain@5b842231ba77f5c045dba54ac5560fed2db780e2 # nightly

      - name: Cache cargo dependencies
        uses: Swatinem/rust-cache@42dc69e1aa15d09112580998cf2ef0119e2e91ae # v2

      # `--locked` pins cargo-fuzz's published lockfile, which depends on an
      # old `rustix` that no longer compiles on recent nightly (it uses
      # internal `rustc_layout_scalar_valid_range_*` attributes that the
      # compiler reserved). Installing without `--locked` lets cargo
      # resolve a compatible newer `rustix`.
      - name: Install cargo-fuzz
        run: cargo install cargo-fuzz

      # libFuzzer runs under AddressSanitizer, which also enables LeakSanitizer
      # by default. At fuzz exit, `crossbeam-epoch`'s thread-local deferred
      # bag still holds objects waiting for epoch advancement — these are
      # not leaks but LSan can't tell. `detect_leaks=0` matches the
      # convention used by `crossbeam-*` crates in their own CI.
      #
      # `-rss_limit_mb=4096` raises libFuzzer's default 2 GiB RSS cap. Each
      # `fuzz_target!` invocation creates a fresh `Tree` and drops it; the
      # nodes go through `crossbeam-epoch`'s deferred destroy queue, which
      # only frees once the global epoch has advanced past two collection
      # cycles. Under sustained throughput the queue grows faster than it
      # drains, and the default cap is reachable within a minute regardless
      # of any correctness issue. 4 GiB gives the smoke test enough headroom
      # to actually exercise the target.
      - name: Run oracle fuzz target for 60s
        env:
          ASAN_OPTIONS: "detect_leaks=0"
        run: cargo +nightly fuzz run tree_oracle -- -max_total_time=60 -rss_limit_mb=4096