[INFO] cloning repository https://github.com/testinnplayin/rust-exercises
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/testinnplayin/rust-exercises" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftestinnplayin%2Frust-exercises", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftestinnplayin%2Frust-exercises'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] a8720b3bc233f7ada3f429aeea9d68a21d803a6f
[INFO] testing testinnplayin/rust-exercises against 1.60.0 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftestinnplayin%2Frust-exercises" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/testinnplayin/rust-exercises on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/testinnplayin/rust-exercises
[INFO] finished tweaking git repo https://github.com/testinnplayin/rust-exercises
[INFO] tweaked toml for git repo https://github.com/testinnplayin/rust-exercises written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/testinnplayin/rust-exercises already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2e3627432d16dce35f3d9d56892aa886cbb893d98790c4bf259080d68e02864b
[INFO] running `Command { std: "docker" "start" "-a" "2e3627432d16dce35f3d9d56892aa886cbb893d98790c4bf259080d68e02864b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2e3627432d16dce35f3d9d56892aa886cbb893d98790c4bf259080d68e02864b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2e3627432d16dce35f3d9d56892aa886cbb893d98790c4bf259080d68e02864b", kill_on_drop: false }`
[INFO] [stdout] 2e3627432d16dce35f3d9d56892aa886cbb893d98790c4bf259080d68e02864b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d643ebc64fbb5dff59d6d6699715a595ef4ef6781da2ddae5e35a6b63c9c7152
[INFO] running `Command { std: "docker" "start" "-a" "d643ebc64fbb5dff59d6d6699715a595ef4ef6781da2ddae5e35a6b63c9c7152", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling chapter-8-exercises v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/statistics_module.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     &vec_of_nums.sort();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let _ = &vec_of_nums.sort();
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.49s
[INFO] running `Command { std: "docker" "inspect" "d643ebc64fbb5dff59d6d6699715a595ef4ef6781da2ddae5e35a6b63c9c7152", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d643ebc64fbb5dff59d6d6699715a595ef4ef6781da2ddae5e35a6b63c9c7152", kill_on_drop: false }`
[INFO] [stdout] d643ebc64fbb5dff59d6d6699715a595ef4ef6781da2ddae5e35a6b63c9c7152
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+1.60.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 21b4788851d9b0028720ba69050473f775d70df3aa25685aaacb78f3289d17bd
[INFO] running `Command { std: "docker" "start" "-a" "21b4788851d9b0028720ba69050473f775d70df3aa25685aaacb78f3289d17bd", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling chapter-8-exercises v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/statistics_module.rs:21:5
[INFO] [stdout]    |
[INFO] [stdout] 21 |     &vec_of_nums.sort();
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 21 |     let _ = &vec_of_nums.sort();
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 7.16s
[INFO] running `Command { std: "docker" "inspect" "21b4788851d9b0028720ba69050473f775d70df3aa25685aaacb78f3289d17bd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21b4788851d9b0028720ba69050473f775d70df3aa25685aaacb78f3289d17bd", kill_on_drop: false }`
[INFO] [stdout] 21b4788851d9b0028720ba69050473f775d70df3aa25685aaacb78f3289d17bd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+1.60.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f2d0e7cbbc50f4a4589b98888eb5ca6f31cbed42565e6b966926996c57522a33
[INFO] running `Command { std: "docker" "start" "-a" "f2d0e7cbbc50f4a4589b98888eb5ca6f31cbed42565e6b966926996c57522a33", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] warning: unused borrow that must be used
[INFO] [stderr]   --> src/statistics_module.rs:21:5
[INFO] [stderr]    |
[INFO] [stderr] 21 |     &vec_of_nums.sort();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 21 |     let _ = &vec_of_nums.sort();
[INFO] [stderr]    |     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: `chapter-8-exercises` (bin "chapter-8-exercises" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.33s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/chapter_8_exercises-a9ebca10939b371e)
[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" "f2d0e7cbbc50f4a4589b98888eb5ca6f31cbed42565e6b966926996c57522a33", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f2d0e7cbbc50f4a4589b98888eb5ca6f31cbed42565e6b966926996c57522a33", kill_on_drop: false }`
[INFO] [stdout] f2d0e7cbbc50f4a4589b98888eb5ca6f31cbed42565e6b966926996c57522a33