[INFO] cloning repository https://github.com/kenjie-sama/rust_pract_1
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kenjie-sama/rust_pract_1" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkenjie-sama%2Frust_pract_1", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkenjie-sama%2Frust_pract_1'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 711ae1954cada34386fb3dd73370b42f76145bb8
[INFO] testing kenjie-sama/rust_pract_1 against beta-2026-04-21 for beta-1.96-2
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkenjie-sama%2Frust_pract_1" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/kenjie-sama/rust_pract_1
[INFO] finished tweaking git repo https://github.com/kenjie-sama/rust_pract_1
[INFO] tweaked toml for git repo https://github.com/kenjie-sama/rust_pract_1 written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/kenjie-sama/rust_pract_1 on toolchain beta-2026-04-21
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/kenjie-sama/rust_pract_1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+beta-2026-04-21" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4807040a2bd02d13fd9b3ed78cbee4fe203b64aa892b292210048cea4306df27
[INFO] running `Command { std: "docker" "start" "-a" "4807040a2bd02d13fd9b3ed78cbee4fe203b64aa892b292210048cea4306df27", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4807040a2bd02d13fd9b3ed78cbee4fe203b64aa892b292210048cea4306df27", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4807040a2bd02d13fd9b3ed78cbee4fe203b64aa892b292210048cea4306df27", kill_on_drop: false }`
[INFO] [stdout] 4807040a2bd02d13fd9b3ed78cbee4fe203b64aa892b292210048cea4306df27
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f5c03958b242fbe3c0e394c258f4a46ab87a33899a41411f5be5bf4601a055c3
[INFO] running `Command { std: "docker" "start" "-a" "f5c03958b242fbe3c0e394c258f4a46ab87a33899a41411f5be5bf4601a055c3", kill_on_drop: false }`
[INFO] [stderr]    Compiling first_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary trailing semicolon
[INFO] [stdout]   --> src/main.rs:39:28
[INFO] [stdout]    |
[INFO] [stdout] 39 |     c.push_str(" updated");;
[INFO] [stdout]    |                            ^ help: remove this semicolon
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(redundant_semicolons)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let mut c = &mut b;
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let mut result: &String = &current;
[INFO] [stdout]    |         ----^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/main.rs:76:29
[INFO] [stdout]    |
[INFO] [stdout] 76 | fn append(current: &String, other: &str)
[INFO] [stdout]    |                             ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let mut result: &String = &current;
[INFO] [stdout]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `memory_demo` is never used
[INFO] [stdout]   --> src/main.rs:28:4
[INFO] [stdout]    |
[INFO] [stdout] 28 | fn memory_demo()
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `create_user` is never used
[INFO] [stdout]   --> src/main.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn create_user(username: &str, password: &str, age: u32, balance: f32) -> User
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `print_user` is never used
[INFO] [stdout]   --> src/main.rs:68:4
[INFO] [stdout]    |
[INFO] [stdout] 68 | fn print_user(user: &User)
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `append` is never used
[INFO] [stdout]   --> src/main.rs:76:4
[INFO] [stdout]    |
[INFO] [stdout] 76 | fn append(current: &String, other: &str)
[INFO] [stdout]    |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_first_char` is never used
[INFO] [stdout]   --> src/main.rs:83:4
[INFO] [stdout]    |
[INFO] [stdout] 83 | fn get_first_char(string: &String) -> Option<char>
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_last_char` is never used
[INFO] [stdout]   --> src/main.rs:87:4
[INFO] [stdout]    |
[INFO] [stdout] 87 | fn get_last_char(string: &String) -> Option<char>
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `User` is never constructed
[INFO] [stdout]   --> src/main.rs:92:8
[INFO] [stdout]    |
[INFO] [stdout] 92 | struct User
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.47s
[INFO] running `Command { std: "docker" "inspect" "f5c03958b242fbe3c0e394c258f4a46ab87a33899a41411f5be5bf4601a055c3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f5c03958b242fbe3c0e394c258f4a46ab87a33899a41411f5be5bf4601a055c3", kill_on_drop: false }`
[INFO] [stdout] f5c03958b242fbe3c0e394c258f4a46ab87a33899a41411f5be5bf4601a055c3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4e5cf9710b6e782935b1c66fa69aabe517f4daab481b8829faa4321bb89524c5
[INFO] running `Command { std: "docker" "start" "-a" "4e5cf9710b6e782935b1c66fa69aabe517f4daab481b8829faa4321bb89524c5", kill_on_drop: false }`
[INFO] [stderr]    Compiling first_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary trailing semicolon
[INFO] [stdout]   --> src/main.rs:39:28
[INFO] [stdout]    |
[INFO] [stdout] 39 |     c.push_str(" updated");;
[INFO] [stdout]    |                            ^ help: remove this semicolon
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(redundant_semicolons)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:38:9
[INFO] [stdout]    |
[INFO] [stdout] 38 |     let mut c = &mut b;
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let mut result: &String = &current;
[INFO] [stdout]    |         ----^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/main.rs:76:29
[INFO] [stdout]    |
[INFO] [stdout] 76 | fn append(current: &String, other: &str)
[INFO] [stdout]    |                             ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `result`
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let mut result: &String = &current;
[INFO] [stdout]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `memory_demo` is never used
[INFO] [stdout]   --> src/main.rs:28:4
[INFO] [stdout]    |
[INFO] [stdout] 28 | fn memory_demo()
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `create_user` is never used
[INFO] [stdout]   --> src/main.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn create_user(username: &str, password: &str, age: u32, balance: f32) -> User
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `print_user` is never used
[INFO] [stdout]   --> src/main.rs:68:4
[INFO] [stdout]    |
[INFO] [stdout] 68 | fn print_user(user: &User)
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `append` is never used
[INFO] [stdout]   --> src/main.rs:76:4
[INFO] [stdout]    |
[INFO] [stdout] 76 | fn append(current: &String, other: &str)
[INFO] [stdout]    |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_first_char` is never used
[INFO] [stdout]   --> src/main.rs:83:4
[INFO] [stdout]    |
[INFO] [stdout] 83 | fn get_first_char(string: &String) -> Option<char>
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_last_char` is never used
[INFO] [stdout]   --> src/main.rs:87:4
[INFO] [stdout]    |
[INFO] [stdout] 87 | fn get_last_char(string: &String) -> Option<char>
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `User` is never constructed
[INFO] [stdout]   --> src/main.rs:92:8
[INFO] [stdout]    |
[INFO] [stdout] 92 | struct User
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.24s
[INFO] running `Command { std: "docker" "inspect" "4e5cf9710b6e782935b1c66fa69aabe517f4daab481b8829faa4321bb89524c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4e5cf9710b6e782935b1c66fa69aabe517f4daab481b8829faa4321bb89524c5", kill_on_drop: false }`
[INFO] [stdout] 4e5cf9710b6e782935b1c66fa69aabe517f4daab481b8829faa4321bb89524c5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2026-04-21" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 207eb4c03394fc20bdac2cb38028d7833fb7337060de5e09db1a9b4b9c83623d
[INFO] running `Command { std: "docker" "start" "-a" "207eb4c03394fc20bdac2cb38028d7833fb7337060de5e09db1a9b4b9c83623d", kill_on_drop: false }`
[INFO] [stderr] warning: unnecessary trailing semicolon
[INFO] [stderr]   --> src/main.rs:39:28
[INFO] [stderr]    |
[INFO] [stdout] 
[INFO] [stderr] 39 |     c.push_str(" updated");;
[INFO] [stdout] running 0 tests
[INFO] [stderr]    |                            ^ help: remove this semicolon
[INFO] [stdout] 
[INFO] [stderr]    |
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr]    = note: `#[warn(redundant_semicolons)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:38:9
[INFO] [stderr]    |
[INFO] [stderr] 38 |     let mut c = &mut b;
[INFO] [stderr]    |         ----^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:78:9
[INFO] [stderr]    |
[INFO] [stderr] 78 |     let mut result: &String = &current;
[INFO] [stderr]    |         ----^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `other`
[INFO] [stderr]   --> src/main.rs:76:29
[INFO] [stderr]    |
[INFO] [stderr] 76 | fn append(current: &String, other: &str)
[INFO] [stderr]    |                             ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `result`
[INFO] [stderr]   --> src/main.rs:78:9
[INFO] [stderr]    |
[INFO] [stderr] 78 |     let mut result: &String = &current;
[INFO] [stderr]    |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_result`
[INFO] [stderr] 
[INFO] [stderr] warning: function `memory_demo` is never used
[INFO] [stderr]   --> src/main.rs:28:4
[INFO] [stderr]    |
[INFO] [stderr] 28 | fn memory_demo()
[INFO] [stderr]    |    ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function `create_user` is never used
[INFO] [stderr]   --> src/main.rs:58:4
[INFO] [stderr]    |
[INFO] [stderr] 58 | fn create_user(username: &str, password: &str, age: u32, balance: f32) -> User
[INFO] [stderr]    |    ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function `print_user` is never used
[INFO] [stderr]   --> src/main.rs:68:4
[INFO] [stderr]    |
[INFO] [stderr] 68 | fn print_user(user: &User)
[INFO] [stderr]    |    ^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function `append` is never used
[INFO] [stderr]   --> src/main.rs:76:4
[INFO] [stderr]    |
[INFO] [stderr] 76 | fn append(current: &String, other: &str)
[INFO] [stderr]    |    ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function `get_first_char` is never used
[INFO] [stderr]   --> src/main.rs:83:4
[INFO] [stderr]    |
[INFO] [stderr] 83 | fn get_first_char(string: &String) -> Option<char>
[INFO] [stderr]    |    ^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function `get_last_char` is never used
[INFO] [stderr]   --> src/main.rs:87:4
[INFO] [stderr]    |
[INFO] [stderr] 87 | fn get_last_char(string: &String) -> Option<char>
[INFO] [stderr]    |    ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct `User` is never constructed
[INFO] [stderr]   --> src/main.rs:92:8
[INFO] [stderr]    |
[INFO] [stderr] 92 | struct User
[INFO] [stderr]    |        ^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `first_rust` (bin "first_rust" test) generated 12 warnings (run `cargo fix --bin "first_rust" -p first_rust --tests` to apply 4 suggestions)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/first_rust-67a39ee7a0a4d1a7)
[INFO] running `Command { std: "docker" "inspect" "207eb4c03394fc20bdac2cb38028d7833fb7337060de5e09db1a9b4b9c83623d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "207eb4c03394fc20bdac2cb38028d7833fb7337060de5e09db1a9b4b9c83623d", kill_on_drop: false }`
[INFO] [stdout] 207eb4c03394fc20bdac2cb38028d7833fb7337060de5e09db1a9b4b9c83623d
