[INFO] cloning repository https://github.com/j84guo/ece459-a4
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/j84guo/ece459-a4" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj84guo%2Fece459-a4", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj84guo%2Fece459-a4'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6e9c8128269301aa41b10d397d197d511b8b8916
[INFO] testing j84guo/ece459-a4 against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fj84guo%2Fece459-a4" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/j84guo/ece459-a4 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/j84guo/ece459-a4
[INFO] finished tweaking git repo https://github.com/j84guo/ece459-a4
[INFO] tweaked toml for git repo https://github.com/j84guo/ece459-a4 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/j84guo/ece459-a4 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6e77b74af354adf575062aaa25e37df8ac55b91fa3a61652e873b00a01e3d746
[INFO] running `Command { std: "docker" "start" "-a" "6e77b74af354adf575062aaa25e37df8ac55b91fa3a61652e873b00a01e3d746", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6e77b74af354adf575062aaa25e37df8ac55b91fa3a61652e873b00a01e3d746", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6e77b74af354adf575062aaa25e37df8ac55b91fa3a61652e873b00a01e3d746", kill_on_drop: false }`
[INFO] [stdout] 6e77b74af354adf575062aaa25e37df8ac55b91fa3a61652e873b00a01e3d746
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4e63f33feebf747388b83ae5724babbef7ec90527068632ad4f243159bdd3ecc
[INFO] running `Command { std: "docker" "start" "-a" "4e63f33feebf747388b83ae5724babbef7ec90527068632ad4f243159bdd3ecc", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling version_check v0.9.2
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling cpuid-bool v0.1.2
[INFO] [stderr]    Compiling opaque-debug v0.3.0
[INFO] [stderr]    Compiling hex v0.4.2
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.5
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stderr]    Compiling generic-array v0.14.4
[INFO] [stderr]    Compiling crossbeam-queue v0.2.3
[INFO] [stderr]    Compiling crossbeam-channel v0.4.3
[INFO] [stderr]    Compiling block-buffer v0.9.0
[INFO] [stderr]    Compiling digest v0.9.0
[INFO] [stderr]    Compiling crossbeam-deque v0.7.3
[INFO] [stderr]    Compiling sha2 v0.9.1
[INFO] [stderr]    Compiling crossbeam v0.7.3
[INFO] [stderr]    Compiling lab4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `super::Event`
[INFO] [stdout]  --> src/idea.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::Event;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::Event`
[INFO] [stdout]  --> src/package.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::Event;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]  --> src/student.rs:4:36
[INFO] [stdout]   |
[INFO] [stdout] 4 | use crossbeam::channel::{Receiver, Sender};
[INFO] [stdout]   |                                    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Event`
[INFO] [stdout]  --> src/student.rs:6:33
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::{checksum::Checksum, Event, idea::Idea, package::Package};
[INFO] [stdout]   |                                 ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `num_students`
[INFO] [stdout]   --> src/idea.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     num_students: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `num_packages`
[INFO] [stdout]   --> src/idea.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     num_packages: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Event`
[INFO] [stdout]   --> src/main.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     Event,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:160:9
[INFO] [stdout]     |
[INFO] [stdout] 160 |         idea_send.send(None);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 9.18s
[INFO] running `Command { std: "docker" "inspect" "4e63f33feebf747388b83ae5724babbef7ec90527068632ad4f243159bdd3ecc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e63f33feebf747388b83ae5724babbef7ec90527068632ad4f243159bdd3ecc", kill_on_drop: false }`
[INFO] [stdout] 4e63f33feebf747388b83ae5724babbef7ec90527068632ad4f243159bdd3ecc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c45b811e79b15856e13913a6d803f296d7be9c24df6a6816aa2a419bf43f687b
[INFO] running `Command { std: "docker" "start" "-a" "c45b811e79b15856e13913a6d803f296d7be9c24df6a6816aa2a419bf43f687b", kill_on_drop: false }`
[INFO] [stderr]    Compiling lab4 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `super::Event`
[INFO] [stdout]  --> src/idea.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::Event;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::Event`
[INFO] [stdout]  --> src/package.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::Event;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]  --> src/student.rs:4:36
[INFO] [stdout]   |
[INFO] [stdout] 4 | use crossbeam::channel::{Receiver, Sender};
[INFO] [stdout]   |                                    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Event`
[INFO] [stdout]  --> src/student.rs:6:33
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::{checksum::Checksum, Event, idea::Idea, package::Package};
[INFO] [stdout]   |                                 ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `num_students`
[INFO] [stdout]   --> src/idea.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     num_students: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `num_packages`
[INFO] [stdout]   --> src/idea.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     num_packages: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Event`
[INFO] [stdout]   --> src/main.rs:16:5
[INFO] [stdout]    |
[INFO] [stdout] 16 |     Event,
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::Event`
[INFO] [stdout]  --> src/idea.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::Event;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `super::Event`
[INFO] [stdout]  --> src/package.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::Event;
[INFO] [stdout]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Sender`
[INFO] [stdout]  --> src/student.rs:4:36
[INFO] [stdout]   |
[INFO] [stdout] 4 | use crossbeam::channel::{Receiver, Sender};
[INFO] [stdout]   |                                    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Event`
[INFO] [stdout]  --> src/student.rs:6:33
[INFO] [stdout]   |
[INFO] [stdout] 6 | use super::{checksum::Checksum, Event, idea::Idea, package::Package};
[INFO] [stdout]   |                                 ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:160:9
[INFO] [stdout]     |
[INFO] [stdout] 160 |         idea_send.send(None);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `num_students`
[INFO] [stdout]   --> src/idea.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 |     num_students: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `num_packages`
[INFO] [stdout]   --> src/idea.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     num_packages: usize,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.96s
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "c45b811e79b15856e13913a6d803f296d7be9c24df6a6816aa2a419bf43f687b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c45b811e79b15856e13913a6d803f296d7be9c24df6a6816aa2a419bf43f687b", kill_on_drop: false }`
[INFO] [stdout] c45b811e79b15856e13913a6d803f296d7be9c24df6a6816aa2a419bf43f687b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f66522d1f62f34f1796d44e04d9081a6279cd20f9b31cd76ae1206b91f7f55ca
[INFO] running `Command { std: "docker" "start" "-a" "f66522d1f62f34f1796d44e04d9081a6279cd20f9b31cd76ae1206b91f7f55ca", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stdout] 
[INFO] [stderr] warning: unused import: `super::Event`
[INFO] [stdout] running 0 tests
[INFO] [stderr]  --> src/idea.rs:6:5
[INFO] [stdout] 
[INFO] [stderr]   |
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr] 6 | use super::Event;
[INFO] [stdout] 
[INFO] [stderr]   |     ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stderr]   |
[INFO] [stdout] running 0 tests
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr] warning: unused import: `super::Event`
[INFO] [stdout] 
[INFO] [stderr]  --> src/package.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use super::Event;
[INFO] [stderr]   |     ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Sender`
[INFO] [stderr]  --> src/student.rs:4:36
[INFO] [stderr]   |
[INFO] [stderr] 4 | use crossbeam::channel::{Receiver, Sender};
[INFO] [stderr]   |                                    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `Event`
[INFO] [stderr]  --> src/student.rs:6:33
[INFO] [stderr]   |
[INFO] [stderr] 6 | use super::{checksum::Checksum, Event, idea::Idea, package::Package};
[INFO] [stderr]   |                                 ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `num_students`
[INFO] [stderr]   --> src/idea.rs:17:5
[INFO] [stderr]    |
[INFO] [stderr] 17 |     num_students: usize,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `num_packages`
[INFO] [stderr]   --> src/idea.rs:18:5
[INFO] [stderr]    |
[INFO] [stderr] 18 |     num_packages: usize,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `lab4` (lib) generated 6 warnings
[INFO] [stderr] warning: `lab4` (lib test) generated 6 warnings (6 duplicates)
[INFO] [stderr] warning: unused import: `Event`
[INFO] [stderr]   --> src/main.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     Event,
[INFO] [stderr]    |     ^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]    --> src/main.rs:160:9
[INFO] [stderr]     |
[INFO] [stderr] 160 |         idea_send.send(None);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: `lab4` (bin "lab4" test) generated 2 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/lab4-0abb57f4d49701ea)
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/lab4-0b0701e62bc763fd)
[INFO] [stderr]    Doc-tests lab4
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "f66522d1f62f34f1796d44e04d9081a6279cd20f9b31cd76ae1206b91f7f55ca", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f66522d1f62f34f1796d44e04d9081a6279cd20f9b31cd76ae1206b91f7f55ca", kill_on_drop: false }`
[INFO] [stdout] f66522d1f62f34f1796d44e04d9081a6279cd20f9b31cd76ae1206b91f7f55ca