[INFO] cloning repository https://github.com/lfn3/rs-advent
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/lfn3/rs-advent" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flfn3%2Frs-advent", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flfn3%2Frs-advent'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 0cd62ac239d19477eaffc88b660bb16a793f6cbf
[INFO] testing lfn3/rs-advent against beta-2026-04-21 for beta-1.96-2
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Flfn3%2Frs-advent" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/lfn3/rs-advent
[INFO] finished tweaking git repo https://github.com/lfn3/rs-advent
[INFO] tweaked toml for git repo https://github.com/lfn3/rs-advent written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/lfn3/rs-advent on toolchain beta-2026-04-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/lfn3/rs-advent already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cb979afd6291d1a867b0a07c22a3eaec648f205f326b9c56b841ba0c9f0b7f88
[INFO] running `Command { std: "docker" "start" "-a" "cb979afd6291d1a867b0a07c22a3eaec648f205f326b9c56b841ba0c9f0b7f88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cb979afd6291d1a867b0a07c22a3eaec648f205f326b9c56b841ba0c9f0b7f88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cb979afd6291d1a867b0a07c22a3eaec648f205f326b9c56b841ba0c9f0b7f88", kill_on_drop: false }`
[INFO] [stdout] cb979afd6291d1a867b0a07c22a3eaec648f205f326b9c56b841ba0c9f0b7f88
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4f5511de9d4c4df0d2e6cc55f0ec26b22decf9eb575115a8dc7da3824f170cb6
[INFO] running `Command { std: "docker" "start" "-a" "4f5511de9d4c4df0d2e6cc55f0ec26b22decf9eb575115a8dc7da3824f170cb6", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] [stderr]    Compiling rs-advent v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/eight.rs:15:28
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn get_metadata(data: &mut Iterator<Item = usize>) -> Vec<usize> {
[INFO] [stdout]    |                            ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn get_metadata(data: &mut dyn Iterator<Item = usize>) -> Vec<usize> {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/eight.rs:43:29
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn take_metadata(data: &mut Iterator<Item = usize>, count: usize) -> Vec<usize> {
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn take_metadata(data: &mut dyn Iterator<Item = usize>, count: usize) -> Vec<usize> {
[INFO] [stdout]    |                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/eight.rs:47:27
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn read_header(data: &mut Iterator<Item = usize>) -> (usize, usize) {
[INFO] [stdout]    |                           ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn read_header(data: &mut dyn Iterator<Item = usize>) -> (usize, usize) {
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/five.rs:20:19
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn reduce(i: &mut Iterator<Item = char>) -> String {
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn reduce(i: &mut dyn Iterator<Item = char>) -> String {
[INFO] [stdout]    |                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/five.rs:61:42
[INFO] [stdout]    |
[INFO] [stdout] 61 | fn reduce_without(polymer: char, i: &mut Iterator<Item = char>) -> String {
[INFO] [stdout]    |                                          ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 61 | fn reduce_without(polymer: char, i: &mut dyn Iterator<Item = char>) -> String {
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.40s
[INFO] running `Command { std: "docker" "inspect" "4f5511de9d4c4df0d2e6cc55f0ec26b22decf9eb575115a8dc7da3824f170cb6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4f5511de9d4c4df0d2e6cc55f0ec26b22decf9eb575115a8dc7da3824f170cb6", kill_on_drop: false }`
[INFO] [stdout] 4f5511de9d4c4df0d2e6cc55f0ec26b22decf9eb575115a8dc7da3824f170cb6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e3061ef042f3551b8a81c447c61bcdab3b022d6465aad128f53500de4958012d
[INFO] running `Command { std: "docker" "start" "-a" "e3061ef042f3551b8a81c447c61bcdab3b022d6465aad128f53500de4958012d", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] [stderr]    Compiling rs-advent v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/eight.rs:15:28
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn get_metadata(data: &mut Iterator<Item = usize>) -> Vec<usize> {
[INFO] [stdout]    |                            ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 15 | fn get_metadata(data: &mut dyn Iterator<Item = usize>) -> Vec<usize> {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/eight.rs:43:29
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn take_metadata(data: &mut Iterator<Item = usize>, count: usize) -> Vec<usize> {
[INFO] [stdout]    |                             ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 43 | fn take_metadata(data: &mut dyn Iterator<Item = usize>, count: usize) -> Vec<usize> {
[INFO] [stdout]    |                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/eight.rs:47:27
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn read_header(data: &mut Iterator<Item = usize>) -> (usize, usize) {
[INFO] [stdout]    |                           ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn read_header(data: &mut dyn Iterator<Item = usize>) -> (usize, usize) {
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/five.rs:20:19
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn reduce(i: &mut Iterator<Item = char>) -> String {
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn reduce(i: &mut dyn Iterator<Item = char>) -> String {
[INFO] [stdout]    |                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/five.rs:61:42
[INFO] [stdout]    |
[INFO] [stdout] 61 | fn reduce_without(polymer: char, i: &mut Iterator<Item = char>) -> String {
[INFO] [stdout]    |                                          ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 61 | fn reduce_without(polymer: char, i: &mut dyn Iterator<Item = char>) -> String {
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.42s
[INFO] running `Command { std: "docker" "inspect" "e3061ef042f3551b8a81c447c61bcdab3b022d6465aad128f53500de4958012d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e3061ef042f3551b8a81c447c61bcdab3b022d6465aad128f53500de4958012d", kill_on_drop: false }`
[INFO] [stdout] e3061ef042f3551b8a81c447c61bcdab3b022d6465aad128f53500de4958012d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 50dbacd0c54fdf3a38d1a1b0a7d85f343da01bf61d07fa0b74fbd7a66ede433b
[INFO] running `Command { std: "docker" "start" "-a" "50dbacd0c54fdf3a38d1a1b0a7d85f343da01bf61d07fa0b74fbd7a66ede433b", kill_on_drop: false }`
[INFO] [stderr] warning: `package.edition` is unspecified, defaulting to `2015` while the latest is `2024`
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/eight.rs:15:28
[INFO] [stderr]    |
[INFO] [stderr] 15 | fn get_metadata(data: &mut Iterator<Item = usize>) -> Vec<usize> {
[INFO] [stderr]    |                            ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr]    = note: `#[warn(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stderr] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 15 | fn get_metadata(data: &mut dyn Iterator<Item = usize>) -> Vec<usize> {
[INFO] [stderr]    |                            +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/eight.rs:43:29
[INFO] [stderr]    |
[INFO] [stderr] 43 | fn take_metadata(data: &mut Iterator<Item = usize>, count: usize) -> Vec<usize> {
[INFO] [stderr]    |                             ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 43 | fn take_metadata(data: &mut dyn Iterator<Item = usize>, count: usize) -> Vec<usize> {
[INFO] [stderr]    |                             +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/eight.rs:47:27
[INFO] [stderr]    |
[INFO] [stderr] 47 | fn read_header(data: &mut Iterator<Item = usize>) -> (usize, usize) {
[INFO] [stderr]    |                           ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 47 | fn read_header(data: &mut dyn Iterator<Item = usize>) -> (usize, usize) {
[INFO] [stderr]    |                           +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/five.rs:20:19
[INFO] [stderr]    |
[INFO] [stderr] 20 | fn reduce(i: &mut Iterator<Item = char>) -> String {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 20 | fn reduce(i: &mut dyn Iterator<Item = char>) -> String {
[INFO] [stderr]    |                   +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/five.rs:61:42
[INFO] [stderr]    |
[INFO] [stderr] 61 | fn reduce_without(polymer: char, i: &mut Iterator<Item = char>) -> String {
[INFO] [stderr]    |                                          ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 61 | fn reduce_without(polymer: char, i: &mut dyn Iterator<Item = char>) -> String {
[INFO] [stderr]    |                                          +++
[INFO] [stderr] 
[INFO] [stderr] warning: `rs-advent` (bin "rs-advent" test) generated 5 warnings (run `cargo fix --bin "rs-advent" -p rs-advent --tests` to apply 5 suggestions)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/rs_advent-939b05d39d5f9021)
[INFO] [stdout] 
[INFO] [stdout] running 11 tests
[INFO] [stdout] test eight::test_solve_part_one ... ok
[INFO] [stdout] test one::should_solve_part_one_sample_input ... ok
[INFO] [stdout] test five::test_reduce_without_all ... ok
[INFO] [stdout] test five::test_reduce_without ... ok
[INFO] [stdout] test two::test_has_n ... ok
[INFO] [stdout] test two::test_testable_solve ... ok
[INFO] [stdout] test one::should_solve_sample_input ... ok
[INFO] [stdout] test five::test_solve_part_one ... ok
[INFO] [stdout] test one::should_solve_part_two_sample_input ... ok
[INFO] [stdout] test five::test_flip ... ok
[INFO] [stdout] test nine::test_solve_part_one ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 11 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.02s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "50dbacd0c54fdf3a38d1a1b0a7d85f343da01bf61d07fa0b74fbd7a66ede433b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "50dbacd0c54fdf3a38d1a1b0a7d85f343da01bf61d07fa0b74fbd7a66ede433b", kill_on_drop: false }`
[INFO] [stdout] 50dbacd0c54fdf3a38d1a1b0a7d85f343da01bf61d07fa0b74fbd7a66ede433b
