[INFO] fetching crate jsonrpc-async 2.0.1...
[INFO] testing jsonrpc-async-2.0.1 against master#432e145bd5a974c5b6f4dd9b352891bd7502b69d for pr-87041
[INFO] extracting crate jsonrpc-async 2.0.1 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate jsonrpc-async 2.0.1 on toolchain 432e145bd5a974c5b6f4dd9b352891bd7502b69d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate jsonrpc-async 2.0.1
[INFO] finished tweaking crates.io crate jsonrpc-async 2.0.1
[INFO] tweaked toml for crates.io crate jsonrpc-async 2.0.1 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 9f328fe2b4ed79b06b789a80315f84dc4d21ead39fc34b8ae4ba2fa3df2cccd6
[INFO] running `Command { std: "docker" "start" "-a" "9f328fe2b4ed79b06b789a80315f84dc4d21ead39fc34b8ae4ba2fa3df2cccd6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9f328fe2b4ed79b06b789a80315f84dc4d21ead39fc34b8ae4ba2fa3df2cccd6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9f328fe2b4ed79b06b789a80315f84dc4d21ead39fc34b8ae4ba2fa3df2cccd6", kill_on_drop: false }`
[INFO] [stdout] 9f328fe2b4ed79b06b789a80315f84dc4d21ead39fc34b8ae4ba2fa3df2cccd6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] b3c6210f2d15941cf09c0d73c693945875ffd7677b615490024371bfd4e1f395
[INFO] running `Command { std: "docker" "start" "-a" "b3c6210f2d15941cf09c0d73c693945875ffd7677b615490024371bfd4e1f395", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.73
[INFO] [stderr]    Compiling serde_json v1.0.64
[INFO] [stderr]    Compiling byteorder v1.4.3
[INFO] [stderr]    Compiling instant v0.1.10
[INFO] [stderr]    Compiling tokio v1.8.1
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling signal-hook-registry v1.4.0
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling parking_lot_core v0.8.3
[INFO] [stderr]    Compiling mio v0.7.13
[INFO] [stderr]    Compiling base64-compat v1.0.0
[INFO] [stderr]    Compiling parking_lot v0.11.1
[INFO] [stderr]    Compiling tokio-macros v1.3.0
[INFO] [stderr]    Compiling serde_derive v1.0.126
[INFO] [stderr]    Compiling async-trait v0.1.50
[INFO] [stderr]    Compiling jsonrpc-async v2.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stdout]   --> src/error.rs:22:13
[INFO] [stdout]    |
[INFO] [stdout] 22 | use serde::{Deserialize, Serialize};
[INFO] [stdout]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stdout]   --> src/lib.rs:30:13
[INFO] [stdout]    |
[INFO] [stdout] 30 | use serde::{Deserialize, Serialize};
[INFO] [stdout]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `AsyncWrite`
[INFO] [stdout]  --> src/simple_http.rs:7:48
[INFO] [stdout]   |
[INFO] [stdout] 7 | use tokio::io::{AsyncBufRead, AsyncBufReadExt, AsyncWrite, BufReader, BufWriter};
[INFO] [stdout]   |                                                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ToSocketAddrs`
[INFO] [stdout]  --> src/simple_http.rs:8:29
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio::net::{TcpStream, ToSocketAddrs};
[INFO] [stdout]   |                             ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `AsyncReadExt`
[INFO] [stdout]   --> src/simple_http.rs:46:17
[INFO] [stdout]    |
[INFO] [stdout] 46 | use tokio::io::{AsyncReadExt, AsyncWriteExt};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/simple_http.rs:174:13
[INFO] [stdout]     |
[INFO] [stdout] 174 |     fn from(e: Elapsed) -> Error {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 55.51s
[INFO] running `Command { std: "docker" "inspect" "b3c6210f2d15941cf09c0d73c693945875ffd7677b615490024371bfd4e1f395", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b3c6210f2d15941cf09c0d73c693945875ffd7677b615490024371bfd4e1f395", kill_on_drop: false }`
[INFO] [stdout] b3c6210f2d15941cf09c0d73c693945875ffd7677b615490024371bfd4e1f395
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2c6ba09c61a534d20bf1784f2d12af53eecc61f0f6bf796c2a594898dc5801c6
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "2c6ba09c61a534d20bf1784f2d12af53eecc61f0f6bf796c2a594898dc5801c6", kill_on_drop: false }`
[INFO] [stderr]    Compiling jsonrpc-async v2.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stdout]   --> src/error.rs:22:13
[INFO] [stdout]    |
[INFO] [stdout] 22 | use serde::{Deserialize, Serialize};
[INFO] [stdout]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stdout]   --> src/lib.rs:30:13
[INFO] [stdout]    |
[INFO] [stdout] 30 | use serde::{Deserialize, Serialize};
[INFO] [stdout]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `AsyncWrite`
[INFO] [stdout]  --> src/simple_http.rs:7:48
[INFO] [stdout]   |
[INFO] [stdout] 7 | use tokio::io::{AsyncBufRead, AsyncBufReadExt, AsyncWrite, BufReader, BufWriter};
[INFO] [stdout]   |                                                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ToSocketAddrs`
[INFO] [stdout]  --> src/simple_http.rs:8:29
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio::net::{TcpStream, ToSocketAddrs};
[INFO] [stdout]   |                             ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `AsyncReadExt`
[INFO] [stdout]   --> src/simple_http.rs:46:17
[INFO] [stdout]    |
[INFO] [stdout] 46 | use tokio::io::{AsyncReadExt, AsyncWriteExt};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/simple_http.rs:174:13
[INFO] [stdout]     |
[INFO] [stdout] 174 |     fn from(e: Elapsed) -> Error {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stdout]   --> src/error.rs:22:13
[INFO] [stdout]    |
[INFO] [stdout] 22 | use serde::{Deserialize, Serialize};
[INFO] [stdout]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stdout]   --> src/lib.rs:30:13
[INFO] [stdout]    |
[INFO] [stdout] 30 | use serde::{Deserialize, Serialize};
[INFO] [stdout]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `AsyncWrite`
[INFO] [stdout]  --> src/simple_http.rs:7:48
[INFO] [stdout]   |
[INFO] [stdout] 7 | use tokio::io::{AsyncBufRead, AsyncBufReadExt, AsyncWrite, BufReader, BufWriter};
[INFO] [stdout]   |                                                ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ToSocketAddrs`
[INFO] [stdout]  --> src/simple_http.rs:8:29
[INFO] [stdout]   |
[INFO] [stdout] 8 | use tokio::net::{TcpStream, ToSocketAddrs};
[INFO] [stdout]   |                             ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `AsyncReadExt`
[INFO] [stdout]   --> src/simple_http.rs:46:17
[INFO] [stdout]    |
[INFO] [stdout] 46 | use tokio::io::{AsyncReadExt, AsyncWriteExt};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `e`
[INFO] [stdout]    --> src/simple_http.rs:174:13
[INFO] [stdout]     |
[INFO] [stdout] 174 |     fn from(e: Elapsed) -> Error {
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 4.35s
[INFO] running `Command { std: "docker" "inspect" "2c6ba09c61a534d20bf1784f2d12af53eecc61f0f6bf796c2a594898dc5801c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2c6ba09c61a534d20bf1784f2d12af53eecc61f0f6bf796c2a594898dc5801c6", kill_on_drop: false }`
[INFO] [stdout] 2c6ba09c61a534d20bf1784f2d12af53eecc61f0f6bf796c2a594898dc5801c6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+432e145bd5a974c5b6f4dd9b352891bd7502b69d" "test" "--frozen", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] dbac25734ebb421259f305d69b8f505fe7bb857a2aaf80d41a7538f596f211b3
[INFO] running `Command { std: "docker" "start" "-a" "dbac25734ebb421259f305d69b8f505fe7bb857a2aaf80d41a7538f596f211b3", kill_on_drop: false }`
[INFO] [stderr] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stderr]   --> src/error.rs:22:13
[INFO] [stderr]    |
[INFO] [stderr] 22 | use serde::{Deserialize, Serialize};
[INFO] [stderr]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stderr]   --> src/lib.rs:30:13
[INFO] [stderr]    |
[INFO] [stderr] 30 | use serde::{Deserialize, Serialize};
[INFO] [stderr]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `AsyncWrite`
[INFO] [stderr]  --> src/simple_http.rs:7:48
[INFO] [stderr]   |
[INFO] [stderr] 7 | use tokio::io::{AsyncBufRead, AsyncBufReadExt, AsyncWrite, BufReader, BufWriter};
[INFO] [stderr]   |                                                ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `ToSocketAddrs`
[INFO] [stderr]  --> src/simple_http.rs:8:29
[INFO] [stderr]   |
[INFO] [stderr] 8 | use tokio::net::{TcpStream, ToSocketAddrs};
[INFO] [stderr]   |                             ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `AsyncReadExt`
[INFO] [stderr]   --> src/simple_http.rs:46:17
[INFO] [stderr]    |
[INFO] [stderr] 46 | use tokio::io::{AsyncReadExt, AsyncWriteExt};
[INFO] [stderr]    |                 ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e`
[INFO] [stderr]    --> src/simple_http.rs:174:13
[INFO] [stderr]     |
[INFO] [stderr] 174 |     fn from(e: Elapsed) -> Error {
[INFO] [stderr]     |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stderr]   --> src/error.rs:22:13
[INFO] [stderr]    |
[INFO] [stderr] 22 | use serde::{Deserialize, Serialize};
[INFO] [stderr]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Deserialize`, `Serialize`
[INFO] [stderr]   --> src/lib.rs:30:13
[INFO] [stderr]    |
[INFO] [stderr] 30 | use serde::{Deserialize, Serialize};
[INFO] [stderr]    |             ^^^^^^^^^^^  ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `AsyncWrite`
[INFO] [stderr]  --> src/simple_http.rs:7:48
[INFO] [stderr]   |
[INFO] [stderr] 7 | use tokio::io::{AsyncBufRead, AsyncBufReadExt, AsyncWrite, BufReader, BufWriter};
[INFO] [stderr]   |                                                ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `ToSocketAddrs`
[INFO] [stderr]  --> src/simple_http.rs:8:29
[INFO] [stderr]   |
[INFO] [stderr] 8 | use tokio::net::{TcpStream, ToSocketAddrs};
[INFO] [stderr]   |                             ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `AsyncReadExt`
[INFO] [stderr]   --> src/simple_http.rs:46:17
[INFO] [stderr]    |
[INFO] [stderr] 46 | use tokio::io::{AsyncReadExt, AsyncWriteExt};
[INFO] [stderr]    |                 ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `e`
[INFO] [stderr]    --> src/simple_http.rs:174:13
[INFO] [stderr]     |
[INFO] [stderr] 174 |     fn from(e: Elapsed) -> Error {
[INFO] [stderr]     |             ^ help: if this is intentional, prefix it with an underscore: `_e`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/jsonrpc_async-3441aa172e3aed7d)
[INFO] [stdout] 
[INFO] [stdout] running 14 tests
[INFO] [stdout] test client::tests::sanity ... ok
[INFO] [stdout] test error::tests::test_internal_error ... ok
[INFO] [stdout] test tests::test_arg ... ok
[INFO] [stdout] test tests::response_is_none ... ok
[INFO] [stdout] test tests::batch_response ... ok
[INFO] [stdout] test error::tests::test_invalid_params ... ok
[INFO] [stdout] test error::tests::test_invalid_request ... ok
[INFO] [stdout] test tests::null_result ... ok
[INFO] [stdout] test util::tests::hash_value ... ok
[INFO] [stdout] test error::tests::test_parse_error ... ok
[INFO] [stdout] test tests::response_extract ... ok
[INFO] [stdout] test error::tests::test_method_not_found ... ok
[INFO] [stdout] test simple_http::tests::construct ... ok
[INFO] [stderr]    Doc-tests jsonrpc_async
[INFO] [stdout] test simple_http::tests::test_urls ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 14 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" "dbac25734ebb421259f305d69b8f505fe7bb857a2aaf80d41a7538f596f211b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dbac25734ebb421259f305d69b8f505fe7bb857a2aaf80d41a7538f596f211b3", kill_on_drop: false }`
[INFO] [stdout] dbac25734ebb421259f305d69b8f505fe7bb857a2aaf80d41a7538f596f211b3