[INFO] cloning repository https://github.com/mjpc13/hanoi_tower
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/mjpc13/hanoi_tower" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmjpc13%2Fhanoi_tower", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmjpc13%2Fhanoi_tower'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 35fc8c36ca19da9ec65a1c099c06d1ab9f99bef3
[INFO] testing mjpc13/hanoi_tower against try#7af779037716ae4125ceabb429791b4cf5dd0a43 for pr-136932
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmjpc13%2Fhanoi_tower" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/mjpc13/hanoi_tower on toolchain 7af779037716ae4125ceabb429791b4cf5dd0a43
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+7af779037716ae4125ceabb429791b4cf5dd0a43" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/mjpc13/hanoi_tower
[INFO] finished tweaking git repo https://github.com/mjpc13/hanoi_tower
[INFO] tweaked toml for git repo https://github.com/mjpc13/hanoi_tower written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/mjpc13/hanoi_tower 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" "+7af779037716ae4125ceabb429791b4cf5dd0a43" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+7af779037716ae4125ceabb429791b4cf5dd0a43" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 15bff306b58fc9f880c208f51b6dfea40620ebf1b7ee0dbf56a672dc73c473cc
[INFO] running `Command { std: "docker" "start" "-a" "15bff306b58fc9f880c208f51b6dfea40620ebf1b7ee0dbf56a672dc73c473cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "15bff306b58fc9f880c208f51b6dfea40620ebf1b7ee0dbf56a672dc73c473cc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "15bff306b58fc9f880c208f51b6dfea40620ebf1b7ee0dbf56a672dc73c473cc", kill_on_drop: false }`
[INFO] [stdout] 15bff306b58fc9f880c208f51b6dfea40620ebf1b7ee0dbf56a672dc73c473cc
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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=forbid" "-e" "RUSTDOCFLAGS=--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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+7af779037716ae4125ceabb429791b4cf5dd0a43" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 42ca229fa33ba83dbc55cc9197bd7d954a121d347d8d11e741d99761c1fd31af
[INFO] running `Command { std: "docker" "start" "-a" "42ca229fa33ba83dbc55cc9197bd7d954a121d347d8d11e741d99761c1fd31af", kill_on_drop: false }`
[INFO] [stderr]    Compiling hanoi_tower v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/lib.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter`
[INFO] [stdout]  --> src/engine.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::iter;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/engine.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:67:13
[INFO] [stdout]    |
[INFO] [stdout] 67 |         let mut s1 = Stack::new(n_disks, true);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:68:13
[INFO] [stdout]    |
[INFO] [stdout] 68 |         let mut s2 = Stack::new(n_disks, false);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:69:13
[INFO] [stdout]    |
[INFO] [stdout] 69 |         let mut s3 = Stack::new(n_disks, false);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:70:13
[INFO] [stdout]    |
[INFO] [stdout] 70 |         let mut stacks = [s1,s2,s3];
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |         let mut string: String = String::new();
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `error`
[INFO] [stdout]   --> src/lib.rs:23:17
[INFO] [stdout]    |
[INFO] [stdout] 23 |             Err(error) => Err("Error parsing the input"),
[INFO] [stdout]    |                 ^^^^^ help: if this is intentional, prefix it with an underscore: `_error`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `number` is never read
[INFO] [stdout]  --> src/engine.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Disk{
[INFO] [stdout]   |            ---- field in this struct
[INFO] [stdout] 6 |     pub number: i32,
[INFO] [stdout]   |         ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `fill` is never read
[INFO] [stdout]   --> src/engine.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 24 | pub struct Stack{
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 25 |     pub disks: Vec<Disk>,
[INFO] [stdout] 26 |     pub fill: bool,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `move_disk` is never used
[INFO] [stdout]   --> src/engine.rs:45:12
[INFO] [stdout]    |
[INFO] [stdout] 29 | impl Stack {
[INFO] [stdout]    | ---------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 45 |     pub fn move_disk(&self, other_stack: Stack) -> Result<(), &'static str>{
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> src/engine.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 55 | pub struct Board{
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 56 |     pub stacks: [Stack; 3],
[INFO] [stdout] 57 |     height: i32,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:53:9
[INFO] [stdout]    |
[INFO] [stdout] 53 | /         match prompt().as_str() {
[INFO] [stdout] 54 | |            "A" => play(&config),
[INFO] [stdout] 55 | |            "B" | "exit" => break Ok(()),
[INFO] [stdout] 56 | |            _ => todo!(),
[INFO] [stdout] 57 | |         };
[INFO] [stdout]    | |_________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 53 |         let _ = match prompt().as_str() {
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.68s
[INFO] running `Command { std: "docker" "inspect" "42ca229fa33ba83dbc55cc9197bd7d954a121d347d8d11e741d99761c1fd31af", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "42ca229fa33ba83dbc55cc9197bd7d954a121d347d8d11e741d99761c1fd31af", kill_on_drop: false }`
[INFO] [stdout] 42ca229fa33ba83dbc55cc9197bd7d954a121d347d8d11e741d99761c1fd31af
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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=forbid" "-e" "RUSTDOCFLAGS=--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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+7af779037716ae4125ceabb429791b4cf5dd0a43" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d0e3d680e947905f21bc138c9e488d084a15554141f944f3db38d82b85172556
[INFO] running `Command { std: "docker" "start" "-a" "d0e3d680e947905f21bc138c9e488d084a15554141f944f3db38d82b85172556", kill_on_drop: false }`
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/lib.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter`
[INFO] [stdout]  --> src/engine.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::iter;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/engine.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:67:13
[INFO] [stdout]    |
[INFO] [stdout] 67 |         let mut s1 = Stack::new(n_disks, true);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:68:13
[INFO] [stdout]    |
[INFO] [stdout] 68 |         let mut s2 = Stack::new(n_disks, false);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:69:13
[INFO] [stdout]    |
[INFO] [stdout] 69 |         let mut s3 = Stack::new(n_disks, false);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:70:13
[INFO] [stdout]    |
[INFO] [stdout] 70 |         let mut stacks = [s1,s2,s3];
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |         let mut string: String = String::new();
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `error`
[INFO] [stdout]   --> src/lib.rs:23:17
[INFO] [stdout]    |
[INFO] [stdout] 23 |             Err(error) => Err("Error parsing the input"),
[INFO] [stdout]    |                 ^^^^^ help: if this is intentional, prefix it with an underscore: `_error`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `number` is never read
[INFO] [stdout]  --> src/engine.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Disk{
[INFO] [stdout]   |            ---- field in this struct
[INFO] [stdout] 6 |     pub number: i32,
[INFO] [stdout]   |         ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `fill` is never read
[INFO] [stdout]   --> src/engine.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 24 | pub struct Stack{
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 25 |     pub disks: Vec<Disk>,
[INFO] [stdout] 26 |     pub fill: bool,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `move_disk` is never used
[INFO] [stdout]   --> src/engine.rs:45:12
[INFO] [stdout]    |
[INFO] [stdout] 29 | impl Stack {
[INFO] [stdout]    | ---------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 45 |     pub fn move_disk(&self, other_stack: Stack) -> Result<(), &'static str>{
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> src/engine.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 55 | pub struct Board{
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 56 |     pub stacks: [Stack; 3],
[INFO] [stdout] 57 |     height: i32,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:53:9
[INFO] [stdout]    |
[INFO] [stdout] 53 | /         match prompt().as_str() {
[INFO] [stdout] 54 | |            "A" => play(&config),
[INFO] [stdout] 55 | |            "B" | "exit" => break Ok(()),
[INFO] [stdout] 56 | |            _ => todo!(),
[INFO] [stdout] 57 | |         };
[INFO] [stdout]    | |_________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 53 |         let _ = match prompt().as_str() {
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling hanoi_tower v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::env`
[INFO] [stdout]  --> src/lib.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::env;
[INFO] [stdout]   |     ^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::iter`
[INFO] [stdout]  --> src/engine.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::iter;
[INFO] [stdout]   |     ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::error::Error`
[INFO] [stdout]  --> src/engine.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::error::Error;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:67:13
[INFO] [stdout]    |
[INFO] [stdout] 67 |         let mut s1 = Stack::new(n_disks, true);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:68:13
[INFO] [stdout]    |
[INFO] [stdout] 68 |         let mut s2 = Stack::new(n_disks, false);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:69:13
[INFO] [stdout]    |
[INFO] [stdout] 69 |         let mut s3 = Stack::new(n_disks, false);
[INFO] [stdout]    |             ----^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:70:13
[INFO] [stdout]    |
[INFO] [stdout] 70 |         let mut stacks = [s1,s2,s3];
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/engine.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 |         let mut string: String = String::new();
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `error`
[INFO] [stdout]   --> src/lib.rs:23:17
[INFO] [stdout]    |
[INFO] [stdout] 23 |             Err(error) => Err("Error parsing the input"),
[INFO] [stdout]    |                 ^^^^^ help: if this is intentional, prefix it with an underscore: `_error`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `number` is never read
[INFO] [stdout]  --> src/engine.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub struct Disk{
[INFO] [stdout]   |            ---- field in this struct
[INFO] [stdout] 6 |     pub number: i32,
[INFO] [stdout]   |         ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `fill` is never read
[INFO] [stdout]   --> src/engine.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 24 | pub struct Stack{
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 25 |     pub disks: Vec<Disk>,
[INFO] [stdout] 26 |     pub fill: bool,
[INFO] [stdout]    |         ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `move_disk` is never used
[INFO] [stdout]   --> src/engine.rs:45:12
[INFO] [stdout]    |
[INFO] [stdout] 29 | impl Stack {
[INFO] [stdout]    | ---------- method in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 45 |     pub fn move_disk(&self, other_stack: Stack) -> Result<(), &'static str>{
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `height` is never read
[INFO] [stdout]   --> src/engine.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 55 | pub struct Board{
[INFO] [stdout]    |            ----- field in this struct
[INFO] [stdout] 56 |     pub stacks: [Stack; 3],
[INFO] [stdout] 57 |     height: i32,
[INFO] [stdout]    |     ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:53:9
[INFO] [stdout]    |
[INFO] [stdout] 53 | /         match prompt().as_str() {
[INFO] [stdout] 54 | |            "A" => play(&config),
[INFO] [stdout] 55 | |            "B" | "exit" => break Ok(()),
[INFO] [stdout] 56 | |            _ => todo!(),
[INFO] [stdout] 57 | |         };
[INFO] [stdout]    | |_________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 53 |         let _ = match prompt().as_str() {
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.37s
[INFO] running `Command { std: "docker" "inspect" "d0e3d680e947905f21bc138c9e488d084a15554141f944f3db38d82b85172556", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d0e3d680e947905f21bc138c9e488d084a15554141f944f3db38d82b85172556", kill_on_drop: false }`
[INFO] [stdout] d0e3d680e947905f21bc138c9e488d084a15554141f944f3db38d82b85172556
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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=forbid" "-e" "RUSTDOCFLAGS=--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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+7af779037716ae4125ceabb429791b4cf5dd0a43" "test" "--frozen", kill_on_drop: false }`
[INFO] [stderr] Error response from daemon: mkdir /var/lib/docker/overlay2/893c9464fa31b018bf1b12d17af1c137a45d33d45b3463826f1956cb46317dab-init: no space left on device