[INFO] cloning repository https://github.com/susan-tu/rust-book-exercises
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/susan-tu/rust-book-exercises" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 519cdd9aec859ec823552009fa8460a3c7610701
[INFO] testing susan-tu/rust-book-exercises against beta-2022-02-22 for beta-1.60-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises" "/workspace/builds/worker-25/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-25/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/susan-tu/rust-book-exercises on toolchain beta-2022-02-22
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-02-22" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/susan-tu/rust-book-exercises
[INFO] finished tweaking git repo https://github.com/susan-tu/rust-book-exercises
[INFO] tweaked toml for git repo https://github.com/susan-tu/rust-book-exercises written to /workspace/builds/worker-25/source/Cargo.toml
[INFO] crate git repo https://github.com/susan-tu/rust-book-exercises already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-02-22" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 48264b205a2b8aeed0f322195fd7e4c7a31cfbaa4ede795ddd48bec938da9303
[INFO] running `Command { std: "docker" "start" "-a" "48264b205a2b8aeed0f322195fd7e4c7a31cfbaa4ede795ddd48bec938da9303", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "48264b205a2b8aeed0f322195fd7e4c7a31cfbaa4ede795ddd48bec938da9303", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "48264b205a2b8aeed0f322195fd7e4c7a31cfbaa4ede795ddd48bec938da9303", kill_on_drop: false }`
[INFO] [stdout] 48264b205a2b8aeed0f322195fd7e4c7a31cfbaa4ede795ddd48bec938da9303
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2ce6579c67ed919680f6e8c21a90eb36662d9fb43afbfd42adcf0ba89a7ef495
[INFO] running `Command { std: "docker" "start" "-a" "2ce6579c67ed919680f6e8c21a90eb36662d9fb43afbfd42adcf0ba89a7ef495", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling approx v0.5.0
[INFO] [stderr]    Compiling exercises v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 17.87s
[INFO] running `Command { std: "docker" "inspect" "2ce6579c67ed919680f6e8c21a90eb36662d9fb43afbfd42adcf0ba89a7ef495", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2ce6579c67ed919680f6e8c21a90eb36662d9fb43afbfd42adcf0ba89a7ef495", kill_on_drop: false }`
[INFO] [stdout] 2ce6579c67ed919680f6e8c21a90eb36662d9fb43afbfd42adcf0ba89a7ef495
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 09943e4c7d7e6c8bc628223180e8d1a3bdc5a7bedd8c5cbfb24614a7cf1354f1
[INFO] running `Command { std: "docker" "start" "-a" "09943e4c7d7e6c8bc628223180e8d1a3bdc5a7bedd8c5cbfb24614a7cf1354f1", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling exercises v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]   --> lib.rs:99:9
[INFO] [stdout]    |
[INFO] [stdout] 99 |         relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `relative_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]    --> lib.rs:108:9
[INFO] [stdout]     |
[INFO] [stdout] 108 |         relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in the macro `relative_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]   --> lib.rs:99:9
[INFO] [stdout]    |
[INFO] [stdout] 99 |         relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `relative_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stdout]    --> lib.rs:108:9
[INFO] [stdout]     |
[INFO] [stdout] 108 |         relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in the macro `relative_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 15.61s
[INFO] running `Command { std: "docker" "inspect" "09943e4c7d7e6c8bc628223180e8d1a3bdc5a7bedd8c5cbfb24614a7cf1354f1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "09943e4c7d7e6c8bc628223180e8d1a3bdc5a7bedd8c5cbfb24614a7cf1354f1", kill_on_drop: false }`
[INFO] [stdout] 09943e4c7d7e6c8bc628223180e8d1a3bdc5a7bedd8c5cbfb24614a7cf1354f1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-25/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@sha256:0cd99ca24d8e8c98e67c542213511d985b8778b5bdcbb160e038429496686047" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-02-22" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] b3e89e36710476b260ddd0cff4928702ebba5a7caff2c222f4083b128738c9f2
[INFO] running `Command { std: "docker" "start" "-a" "b3e89e36710476b260ddd0cff4928702ebba5a7caff2c222f4083b128738c9f2", kill_on_drop: false }`
[INFO] [stderr] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stderr]   --> lib.rs:99:9
[INFO] [stderr]    |
[INFO] [stderr] 99 |         relative_eq!(mean, 3.83333, epsilon = f32::EPSILON);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this warning originates in the macro `relative_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `Relative::<A, B>::eq` that must be used
[INFO] [stderr]    --> lib.rs:108:9
[INFO] [stderr]     |
[INFO] [stderr] 108 |         relative_eq!(mean, 2.0, epsilon = f32::EPSILON);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: this warning originates in the macro `relative_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: `exercises` (lib test) generated 2 warnings
[INFO] [stderr] warning: `exercises` (bin "exercises" test) generated 2 warnings (2 duplicates)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/exercises-7e03559c5c50d865)
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test tests::it_calculates_mean_median_mode ... ok
[INFO] [stdout] test tests::it_calculates_mean_median_mode_of_empty_list ... ok
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/exercises-7084143eea10130b)
[INFO] [stdout] test tests::it_calculates_mean_median_mode_of_single_elem_list ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.02s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 3 tests
[INFO] [stdout] test lib::tests::it_calculates_mean_median_mode ... ok
[INFO] [stdout] test lib::tests::it_calculates_mean_median_mode_of_empty_list ... ok
[INFO] [stderr]    Doc-tests exercises
[INFO] [stdout] test lib::tests::it_calculates_mean_median_mode_of_single_elem_list ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 3 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.02s
[INFO] [stdout] 
[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" "b3e89e36710476b260ddd0cff4928702ebba5a7caff2c222f4083b128738c9f2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b3e89e36710476b260ddd0cff4928702ebba5a7caff2c222f4083b128738c9f2", kill_on_drop: false }`
[INFO] [stdout] b3e89e36710476b260ddd0cff4928702ebba5a7caff2c222f4083b128738c9f2