[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-2022-04-10 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsusan-tu%2Frust-book-exercises" "/workspace/builds/worker-93/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-93/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/susan-tu/rust-book-exercises on toolchain beta-2022-04-10
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2022-04-10" "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-93/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-2022-04-10" "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-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 17138f5ad471db46ff08285a750251ceeb7e203faa8ced5f6de43c5b7acf4c65
[INFO] running `Command { std: "docker" "start" "-a" "17138f5ad471db46ff08285a750251ceeb7e203faa8ced5f6de43c5b7acf4c65", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "17138f5ad471db46ff08285a750251ceeb7e203faa8ced5f6de43c5b7acf4c65", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "17138f5ad471db46ff08285a750251ceeb7e203faa8ced5f6de43c5b7acf4c65", kill_on_drop: false }`
[INFO] [stdout] 17138f5ad471db46ff08285a750251ceeb7e203faa8ced5f6de43c5b7acf4c65
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a5b1ffb4b18d93ffa9ec4d7aee2b8adea3b91bde1ba7699d702c397cd66f3d7d
[INFO] running `Command { std: "docker" "start" "-a" "a5b1ffb4b18d93ffa9ec4d7aee2b8adea3b91bde1ba7699d702c397cd66f3d7d", 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 46.88s
[INFO] running `Command { std: "docker" "inspect" "a5b1ffb4b18d93ffa9ec4d7aee2b8adea3b91bde1ba7699d702c397cd66f3d7d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a5b1ffb4b18d93ffa9ec4d7aee2b8adea3b91bde1ba7699d702c397cd66f3d7d", kill_on_drop: false }`
[INFO] [stdout] a5b1ffb4b18d93ffa9ec4d7aee2b8adea3b91bde1ba7699d702c397cd66f3d7d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a5651bcc3fc5e58ed76559bb4f28f2c66938dabacacaa6a938d84734d4cb4908
[INFO] running `Command { std: "docker" "start" "-a" "a5651bcc3fc5e58ed76559bb4f28f2c66938dabacacaa6a938d84734d4cb4908", 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 56.85s
[INFO] [stderr]   Executable unittests lib.rs (/opt/rustwide/target/debug/deps/exercises-7e03559c5c50d865)
[INFO] [stderr]   Executable unittests main.rs (/opt/rustwide/target/debug/deps/exercises-7084143eea10130b)
[INFO] running `Command { std: "docker" "inspect" "a5651bcc3fc5e58ed76559bb4f28f2c66938dabacacaa6a938d84734d4cb4908", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a5651bcc3fc5e58ed76559bb4f28f2c66938dabacacaa6a938d84734d4cb4908", kill_on_drop: false }`
[INFO] [stdout] a5651bcc3fc5e58ed76559bb4f28f2c66938dabacacaa6a938d84734d4cb4908
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2022-04-10" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] c174b743eb91fdc317e8bfe8349ae36d5a18d49698f82a09c719a58164663f68
[INFO] running `Command { std: "docker" "start" "-a" "c174b743eb91fdc317e8bfe8349ae36d5a18d49698f82a09c719a58164663f68", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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 1.19s
[INFO] [stderr]      Running unittests lib.rs (/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] [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 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests main.rs (/opt/rustwide/target/debug/deps/exercises-7084143eea10130b)
[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] [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 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests exercises
[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" "c174b743eb91fdc317e8bfe8349ae36d5a18d49698f82a09c719a58164663f68", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c174b743eb91fdc317e8bfe8349ae36d5a18d49698f82a09c719a58164663f68", kill_on_drop: false }`
[INFO] [stdout] c174b743eb91fdc317e8bfe8349ae36d5a18d49698f82a09c719a58164663f68