[INFO] fetching crate phoenix-channels 0.1.4...
[INFO] testing phoenix-channels-0.1.4 against try#ce59db7a1b1b012fb2793c4641c1bdecad7a128b for pr-85530
[INFO] extracting crate phoenix-channels 0.1.4 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate phoenix-channels 0.1.4 on toolchain ce59db7a1b1b012fb2793c4641c1bdecad7a128b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate phoenix-channels 0.1.4
[INFO] finished tweaking crates.io crate phoenix-channels 0.1.4
[INFO] tweaked toml for crates.io crate phoenix-channels 0.1.4 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded slog-stdlog v4.1.0
[INFO] [stderr]   Downloaded tokio-tls v0.2.1
[INFO] [stderr]   Downloaded websocket v0.23.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cf662d888305a9ed48efc95f9656a9f137c1ce5cdcae492f50cc5d3fe39b4b39
[INFO] running `Command { std: "docker" "start" "-a" "cf662d888305a9ed48efc95f9656a9f137c1ce5cdcae492f50cc5d3fe39b4b39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cf662d888305a9ed48efc95f9656a9f137c1ce5cdcae492f50cc5d3fe39b4b39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cf662d888305a9ed48efc95f9656a9f137c1ce5cdcae492f50cc5d3fe39b4b39", kill_on_drop: false }`
[INFO] [stdout] cf662d888305a9ed48efc95f9656a9f137c1ce5cdcae492f50cc5d3fe39b4b39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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=forbid" "-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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8d4689dc14fbd871e7f7e6b4bc12447ee7567a1c42e520120b25aadf1c543926
[INFO] running `Command { std: "docker" "start" "-a" "8d4689dc14fbd871e7f7e6b4bc12447ee7567a1c42e520120b25aadf1c543926", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.95
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling pkg-config v0.3.19
[INFO] [stderr]    Compiling cc v1.0.68
[INFO] [stderr]    Compiling futures v0.1.31
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling version_check v0.1.5
[INFO] [stderr]    Compiling once_cell v1.7.2
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling httparse v1.4.1
[INFO] [stderr]    Compiling safemem v0.3.3
[INFO] [stderr]    Compiling serde v1.0.126
[INFO] [stderr]    Compiling arc-swap v1.3.0
[INFO] [stderr]    Compiling typeable v0.1.2
[INFO] [stderr]    Compiling itoa v0.4.7
[INFO] [stderr]    Compiling sha1 v0.6.0
[INFO] [stderr]    Compiling base64 v0.9.3
[INFO] [stderr]    Compiling base64 v0.10.1
[INFO] [stderr]    Compiling unicase v1.4.2
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling log v0.3.9
[INFO] [stderr]    Compiling mime v0.2.6
[INFO] [stderr]    Compiling slog-scope v4.4.0
[INFO] [stderr]    Compiling slog-stdlog v4.1.0
[INFO] [stderr]    Compiling tokio-sync v0.1.8
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling net2 v0.2.37
[INFO] [stderr]    Compiling parking_lot_core v0.6.2
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling time v0.1.43
[INFO] [stderr]    Compiling openssl-sys v0.9.63
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling bytes v0.4.12
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling parking_lot v0.9.0
[INFO] [stderr]    Compiling tokio-executor v0.1.10
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling mio v0.6.23
[INFO] [stderr]    Compiling hyper v0.10.16
[INFO] [stderr]    Compiling tokio-io v0.1.13
[INFO] [stderr]    Compiling openssl v0.10.34
[INFO] [stderr]    Compiling native-tls v0.2.7
[INFO] [stderr]    Compiling tokio-codec v0.1.2
[INFO] [stderr]    Compiling tokio-reactor v0.1.12
[INFO] [stderr]    Compiling tokio-tcp v0.1.4
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling tokio-tls v0.2.1
[INFO] [stderr]    Compiling websocket v0.23.0
[INFO] [stderr]    Compiling phoenix-channels v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/sender.rs:44:43
[INFO] [stdout]    |
[INFO] [stdout] 44 |     pub fn heartbeat(&mut self) -> Result<(u32), MessageError> {
[INFO] [stdout]    |                                           ^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `logger`
[INFO] [stdout]   --> src/client.rs:72:5
[INFO] [stdout]    |
[INFO] [stdout] 72 |     logger: slog::Logger,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `logger`
[INFO] [stdout]   --> src/receiver.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     logger: slog::Logger,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/client.rs:107:17
[INFO] [stdout]     |
[INFO] [stdout] 107 |                 sender.heartbeat();
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 32.53s
[INFO] running `Command { std: "docker" "inspect" "8d4689dc14fbd871e7f7e6b4bc12447ee7567a1c42e520120b25aadf1c543926", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8d4689dc14fbd871e7f7e6b4bc12447ee7567a1c42e520120b25aadf1c543926", kill_on_drop: false }`
[INFO] [stdout] 8d4689dc14fbd871e7f7e6b4bc12447ee7567a1c42e520120b25aadf1c543926
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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=forbid" "-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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c03b7576473dac63a0be6778278907817508fc21b83f96176700d09828107b62
[INFO] running `Command { std: "docker" "start" "-a" "c03b7576473dac63a0be6778278907817508fc21b83f96176700d09828107b62", kill_on_drop: false }`
[INFO] [stderr]    Compiling phoenix-channels v0.1.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/sender.rs:44:43
[INFO] [stdout]    |
[INFO] [stdout] 44 |     pub fn heartbeat(&mut self) -> Result<(u32), MessageError> {
[INFO] [stdout]    |                                           ^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `logger`
[INFO] [stdout]   --> src/client.rs:72:5
[INFO] [stdout]    |
[INFO] [stdout] 72 |     logger: slog::Logger,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `logger`
[INFO] [stdout]   --> src/receiver.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     logger: slog::Logger,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/client.rs:107:17
[INFO] [stdout]     |
[INFO] [stdout] 107 |                 sender.heartbeat();
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/sender.rs:44:43
[INFO] [stdout]    |
[INFO] [stdout] 44 |     pub fn heartbeat(&mut self) -> Result<(u32), MessageError> {
[INFO] [stdout]    |                                           ^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `logger`
[INFO] [stdout]   --> src/client.rs:72:5
[INFO] [stdout]    |
[INFO] [stdout] 72 |     logger: slog::Logger,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `logger`
[INFO] [stdout]   --> src/receiver.rs:11:5
[INFO] [stdout]    |
[INFO] [stdout] 11 |     logger: slog::Logger,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/client.rs:107:17
[INFO] [stdout]     |
[INFO] [stdout] 107 |                 sender.heartbeat();
[INFO] [stdout]     |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.92s
[INFO] running `Command { std: "docker" "inspect" "c03b7576473dac63a0be6778278907817508fc21b83f96176700d09828107b62", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c03b7576473dac63a0be6778278907817508fc21b83f96176700d09828107b62", kill_on_drop: false }`
[INFO] [stdout] c03b7576473dac63a0be6778278907817508fc21b83f96176700d09828107b62
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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=forbid" "-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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+ce59db7a1b1b012fb2793c4641c1bdecad7a128b" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 49014d46618eb094b13ffba2be509aea6f4dc17f4a48f12a7fddaaa148d1d458
[INFO] running `Command { std: "docker" "start" "-a" "49014d46618eb094b13ffba2be509aea6f4dc17f4a48f12a7fddaaa148d1d458", kill_on_drop: false }`
[INFO] [stderr] warning: unnecessary parentheses around type
[INFO] [stderr]   --> src/sender.rs:44:43
[INFO] [stderr]    |
[INFO] [stderr] 44 |     pub fn heartbeat(&mut self) -> Result<(u32), MessageError> {
[INFO] [stderr]    |                                           ^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `logger`
[INFO] [stderr]   --> src/client.rs:72:5
[INFO] [stderr]    |
[INFO] [stderr] 72 |     logger: slog::Logger,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `logger`
[INFO] [stderr]   --> src/receiver.rs:11:5
[INFO] [stderr]    |
[INFO] [stderr] 11 |     logger: slog::Logger,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]    --> src/client.rs:107:17
[INFO] [stderr]     |
[INFO] [stderr] 107 |                 sender.heartbeat();
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around type
[INFO] [stderr]   --> src/sender.rs:44:43
[INFO] [stderr]    |
[INFO] [stderr] 44 |     pub fn heartbeat(&mut self) -> Result<(u32), MessageError> {
[INFO] [stderr]    |                                           ^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `logger`
[INFO] [stderr]   --> src/client.rs:72:5
[INFO] [stderr]    |
[INFO] [stderr] 72 |     logger: slog::Logger,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: field is never read: `logger`
[INFO] [stderr]   --> src/receiver.rs:11:5
[INFO] [stderr]    |
[INFO] [stderr] 11 |     logger: slog::Logger,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]    --> src/client.rs:107:17
[INFO] [stderr]     |
[INFO] [stderr] 107 |                 sender.heartbeat();
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.09s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/phoenix_channels-efad77fd6b56760c)
[INFO] [stdout] running 0 tests
[INFO] [stderr]    Doc-tests phoenix-channels
[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] warning: unnecessary parentheses around type
[INFO] [stdout] 
[INFO] [stderr]   --> /opt/rustwide/workdir/src/sender.rs:44:43
[INFO] [stdout] running 0 tests
[INFO] [stderr]    |
[INFO] [stdout] 
[INFO] [stderr] 44 |     pub fn heartbeat(&mut self) -> Result<(u32), MessageError> {
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr]    |                                           ^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] running `Command { std: "docker" "inspect" "49014d46618eb094b13ffba2be509aea6f4dc17f4a48f12a7fddaaa148d1d458", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "49014d46618eb094b13ffba2be509aea6f4dc17f4a48f12a7fddaaa148d1d458", kill_on_drop: false }`
[INFO] [stdout] 49014d46618eb094b13ffba2be509aea6f4dc17f4a48f12a7fddaaa148d1d458