[INFO] fetching crate tasks-framework 0.1.0...
[INFO] building tasks-framework-0.1.0 against 1.75.0 for beta-1.76-1
[INFO] extracting crate tasks-framework 0.1.0 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate tasks-framework 0.1.0 on toolchain 1.75.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tasks-framework 0.1.0
[INFO] finished tweaking crates.io crate tasks-framework 0.1.0
[INFO] tweaked toml for crates.io crate tasks-framework 0.1.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded lock-free-stack v0.1.1
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e650e93d8720f8402b2c263f831f2ae40cf71442d303a7d23148ab972547f21f
[INFO] running `Command { std: "docker" "start" "-a" "e650e93d8720f8402b2c263f831f2ae40cf71442d303a7d23148ab972547f21f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e650e93d8720f8402b2c263f831f2ae40cf71442d303a7d23148ab972547f21f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e650e93d8720f8402b2c263f831f2ae40cf71442d303a7d23148ab972547f21f", kill_on_drop: false }`
[INFO] [stdout] e650e93d8720f8402b2c263f831f2ae40cf71442d303a7d23148ab972547f21f
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c348776fb79f14fe31769e52f11d8b5f06ac0a3050600e7aaaf18786e012bdc1
[INFO] running `Command { std: "docker" "start" "-a" "c348776fb79f14fe31769e52f11d8b5f06ac0a3050600e7aaaf18786e012bdc1", kill_on_drop: false }`
[INFO] [stderr]    Compiling num_cpus v1.16.0
[INFO] [stderr]    Compiling lock-free-stack v0.1.1
[INFO] [stderr]    Compiling threadpool v1.8.1
[INFO] [stderr]    Compiling tasks-framework v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tasks.rs:30:20
[INFO] [stdout]    |
[INFO] [stdout] 30 |             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this usage of `panic!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]    = note: the `panic!()` macro supports formatting, so there's no need for the `format!()` macro here
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 30 -             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout] 30 +             panic!("unknown old state: {}", old_state);
[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 0.61s
[INFO] running `Command { std: "docker" "inspect" "c348776fb79f14fe31769e52f11d8b5f06ac0a3050600e7aaaf18786e012bdc1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c348776fb79f14fe31769e52f11d8b5f06ac0a3050600e7aaaf18786e012bdc1", kill_on_drop: false }`
[INFO] [stdout] c348776fb79f14fe31769e52f11d8b5f06ac0a3050600e7aaaf18786e012bdc1
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e978893f4b285e22f63edf5b9906f86df75adcfd0f61ee58371993ec4936c5b3
[INFO] running `Command { std: "docker" "start" "-a" "e978893f4b285e22f63edf5b9906f86df75adcfd0f61ee58371993ec4936c5b3", kill_on_drop: false }`
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tasks.rs:30:20
[INFO] [stdout]    |
[INFO] [stdout] 30 |             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this usage of `panic!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]    = note: the `panic!()` macro supports formatting, so there's no need for the `format!()` macro here
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 30 -             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout] 30 +             panic!("unknown old state: {}", old_state);
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling tasks-framework v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> tests/tasks.rs:66:9
[INFO] [stdout]    |
[INFO] [stdout] 66 |     for i in 0 .. 10 {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tasks.rs:30:20
[INFO] [stdout]    |
[INFO] [stdout] 30 |             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this usage of `panic!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]    = note: the `panic!()` macro supports formatting, so there's no need for the `format!()` macro here
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 30 -             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout] 30 +             panic!("unknown old state: {}", old_state);
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.71s
[INFO] running `Command { std: "docker" "inspect" "e978893f4b285e22f63edf5b9906f86df75adcfd0f61ee58371993ec4936c5b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e978893f4b285e22f63edf5b9906f86df75adcfd0f61ee58371993ec4936c5b3", kill_on_drop: false }`
[INFO] [stdout] e978893f4b285e22f63edf5b9906f86df75adcfd0f61ee58371993ec4936c5b3
[INFO] building tasks-framework-0.1.0 against beta-2023-12-22 for beta-1.76-1
[INFO] extracting crate tasks-framework 0.1.0 into /workspace/builds/worker-4-tc2/source
[INFO] validating manifest of crates.io crate tasks-framework 0.1.0 on toolchain beta-2023-12-22
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2023-12-22" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tasks-framework 0.1.0
[INFO] finished tweaking crates.io crate tasks-framework 0.1.0
[INFO] tweaked toml for crates.io crate tasks-framework 0.1.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2023-12-22" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2023-12-22" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2023-12-22" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c2b4bdb32e547c6097670eb2b7195bbd207128af2bc9513eee9cd2ee69a8e06c
[INFO] running `Command { std: "docker" "start" "-a" "c2b4bdb32e547c6097670eb2b7195bbd207128af2bc9513eee9cd2ee69a8e06c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c2b4bdb32e547c6097670eb2b7195bbd207128af2bc9513eee9cd2ee69a8e06c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c2b4bdb32e547c6097670eb2b7195bbd207128af2bc9513eee9cd2ee69a8e06c", kill_on_drop: false }`
[INFO] [stdout] c2b4bdb32e547c6097670eb2b7195bbd207128af2bc9513eee9cd2ee69a8e06c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2023-12-22" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 54836dfa8834a6b59ff0b57337d201b6d3f65899858187784b6194a6b1172d09
[INFO] running `Command { std: "docker" "start" "-a" "54836dfa8834a6b59ff0b57337d201b6d3f65899858187784b6194a6b1172d09", kill_on_drop: false }`
[INFO] [stderr]    Compiling lock-free-stack v0.1.1
[INFO] [stderr]    Compiling num_cpus v1.16.0
[INFO] [stderr]    Compiling threadpool v1.8.1
[INFO] [stderr]    Compiling tasks-framework v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tasks.rs:30:20
[INFO] [stdout]    |
[INFO] [stdout] 30 |             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this usage of `panic!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]    = note: the `panic!()` macro supports formatting, so there's no need for the `format!()` macro here
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 30 -             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout] 30 +             panic!("unknown old state: {}", old_state);
[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 0.52s
[INFO] running `Command { std: "docker" "inspect" "54836dfa8834a6b59ff0b57337d201b6d3f65899858187784b6194a6b1172d09", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "54836dfa8834a6b59ff0b57337d201b6d3f65899858187784b6194a6b1172d09", kill_on_drop: false }`
[INFO] [stdout] 54836dfa8834a6b59ff0b57337d201b6d3f65899858187784b6194a6b1172d09
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2023-12-22" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c9f30695733dd003294c10facbd406fad87d1a6b929289047e3baead3db5efc2
[INFO] running `Command { std: "docker" "start" "-a" "c9f30695733dd003294c10facbd406fad87d1a6b929289047e3baead3db5efc2", kill_on_drop: false }`
[INFO] [stderr]    Compiling tasks-framework v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tasks.rs:30:20
[INFO] [stdout]    |
[INFO] [stdout] 30 |             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this usage of `panic!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]    = note: the `panic!()` macro supports formatting, so there's no need for the `format!()` macro here
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 30 -             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout] 30 +             panic!("unknown old state: {}", old_state);
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> tests/tasks.rs:66:9
[INFO] [stdout]    |
[INFO] [stdout] 66 |     for i in 0 .. 10 {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tasks.rs:30:20
[INFO] [stdout]    |
[INFO] [stdout] 30 |             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout]    |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this usage of `panic!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]    = note: the `panic!()` macro supports formatting, so there's no need for the `format!()` macro here
[INFO] [stdout]    = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: remove the `format!(..)` macro call
[INFO] [stdout]    |
[INFO] [stdout] 30 -             panic!(format!("unknown old state: {}", old_state));
[INFO] [stdout] 30 +             panic!("unknown old state: {}", old_state);
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.69s
[INFO] running `Command { std: "docker" "inspect" "c9f30695733dd003294c10facbd406fad87d1a6b929289047e3baead3db5efc2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9f30695733dd003294c10facbd406fad87d1a6b929289047e3baead3db5efc2", kill_on_drop: false }`
[INFO] [stdout] c9f30695733dd003294c10facbd406fad87d1a6b929289047e3baead3db5efc2
