[INFO] cloning repository https://github.com/zasekle/rust_book_chapter_20
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zasekle/rust_book_chapter_20" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzasekle%2Frust_book_chapter_20", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzasekle%2Frust_book_chapter_20'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f0e23e9eb587aa8aa5e94a3531c29ee791314282
[INFO] testing zasekle/rust_book_chapter_20 against 1.84.0 for beta-1.85-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzasekle%2Frust_book_chapter_20" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/zasekle/rust_book_chapter_20 on toolchain 1.84.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.84.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/zasekle/rust_book_chapter_20
[INFO] finished tweaking git repo https://github.com/zasekle/rust_book_chapter_20
[INFO] tweaked toml for git repo https://github.com/zasekle/rust_book_chapter_20 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/zasekle/rust_book_chapter_20 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" "+1.84.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:86ea7c7af713d31e8cfdb68a6d0db50b5cf7cbeecde3d112f9f257f747318d36" "/opt/rustwide/cargo-home/bin/cargo" "+1.84.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f2cf5f6106920092ae03e39376fda26f943a94046abb49c962aa39f073555bea
[INFO] running `Command { std: "docker" "start" "-a" "f2cf5f6106920092ae03e39376fda26f943a94046abb49c962aa39f073555bea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f2cf5f6106920092ae03e39376fda26f943a94046abb49c962aa39f073555bea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f2cf5f6106920092ae03e39376fda26f943a94046abb49c962aa39f073555bea", kill_on_drop: false }`
[INFO] [stdout] f2cf5f6106920092ae03e39376fda26f943a94046abb49c962aa39f073555bea
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:86ea7c7af713d31e8cfdb68a6d0db50b5cf7cbeecde3d112f9f257f747318d36" "/opt/rustwide/cargo-home/bin/cargo" "+1.84.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8d49c25c006efd4e200670b670058152e59d28ac0f5e2e8936acd4713c679045
[INFO] running `Command { std: "docker" "start" "-a" "8d49c25c006efd4e200670b670058152e59d28ac0f5e2e8936acd4713c679045", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_book_chapter_20 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `thread`
[INFO] [stdout]  --> src/main.rs:7:23
[INFO] [stdout]   |
[INFO] [stdout] 7 | }, num::NonZeroUsize, thread};
[INFO] [stdout]   |                       ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::time::Duration`
[INFO] [stdout]  --> src/main.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::time::Duration;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.72s
[INFO] running `Command { std: "docker" "inspect" "8d49c25c006efd4e200670b670058152e59d28ac0f5e2e8936acd4713c679045", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8d49c25c006efd4e200670b670058152e59d28ac0f5e2e8936acd4713c679045", kill_on_drop: false }`
[INFO] [stdout] 8d49c25c006efd4e200670b670058152e59d28ac0f5e2e8936acd4713c679045
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:86ea7c7af713d31e8cfdb68a6d0db50b5cf7cbeecde3d112f9f257f747318d36" "/opt/rustwide/cargo-home/bin/cargo" "+1.84.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f65947311845d0c45de1a8adf9583c3d5866455b7751335f1369cb4f588bfbed
[INFO] running `Command { std: "docker" "start" "-a" "f65947311845d0c45de1a8adf9583c3d5866455b7751335f1369cb4f588bfbed", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_book_chapter_20 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `thread`
[INFO] [stdout]  --> src/main.rs:7:23
[INFO] [stdout]   |
[INFO] [stdout] 7 | }, num::NonZeroUsize, thread};
[INFO] [stdout]   |                       ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::time::Duration`
[INFO] [stdout]  --> src/main.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 8 | use std::time::Duration;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.38s
[INFO] running `Command { std: "docker" "inspect" "f65947311845d0c45de1a8adf9583c3d5866455b7751335f1369cb4f588bfbed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f65947311845d0c45de1a8adf9583c3d5866455b7751335f1369cb4f588bfbed", kill_on_drop: false }`
[INFO] [stdout] f65947311845d0c45de1a8adf9583c3d5866455b7751335f1369cb4f588bfbed
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:86ea7c7af713d31e8cfdb68a6d0db50b5cf7cbeecde3d112f9f257f747318d36" "/opt/rustwide/cargo-home/bin/cargo" "+1.84.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e9dca0e878839ccb1fa9b82f19ba0e1fa2f92cf1c1349b5f1fe472e68e3d7f8c
[INFO] running `Command { std: "docker" "start" "-a" "e9dca0e878839ccb1fa9b82f19ba0e1fa2f92cf1c1349b5f1fe472e68e3d7f8c", kill_on_drop: false }`
[INFO] [stderr] warning: unused import: `thread`
[INFO] [stderr]  --> src/main.rs:7:23
[INFO] [stderr]   |
[INFO] [stderr] 7 | }, num::NonZeroUsize, thread};
[INFO] [stderr]   |                       ^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::time::Duration`
[INFO] [stderr]  --> src/main.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::time::Duration;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `rust_book_chapter_20` (bin "rust_book_chapter_20" test) generated 2 warnings (run `cargo fix --bin "rust_book_chapter_20" --tests` to apply 2 suggestions)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/rust_book_chapter_20-45c3861aef80acf8)
[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] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/rust_book_chapter_20-92c84af2a8135fe2)
[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] [stderr]    Doc-tests rust_book_chapter_20
[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" "e9dca0e878839ccb1fa9b82f19ba0e1fa2f92cf1c1349b5f1fe472e68e3d7f8c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e9dca0e878839ccb1fa9b82f19ba0e1fa2f92cf1c1349b5f1fe472e68e3d7f8c", kill_on_drop: false }`
[INFO] [stdout] e9dca0e878839ccb1fa9b82f19ba0e1fa2f92cf1c1349b5f1fe472e68e3d7f8c