[INFO] fetching crate utile_cli 0.3.2...
[INFO] testing utile_cli-0.3.2 against beta-2021-08-01 for beta-1.55-1
[INFO] extracting crate utile_cli 0.3.2 into /workspace/builds/worker-93/source
[INFO] validating manifest of crates.io crate utile_cli 0.3.2 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate utile_cli 0.3.2
[INFO] finished tweaking crates.io crate utile_cli 0.3.2
[INFO] tweaked toml for crates.io crate utile_cli 0.3.2 written to /workspace/builds/worker-93/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "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" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8d21d88b2a1998e1d653bbd44bf3d06e47f610d3b3b2fed08f5d661624be2505
[INFO] running `Command { std: "docker" "start" "-a" "8d21d88b2a1998e1d653bbd44bf3d06e47f610d3b3b2fed08f5d661624be2505", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8d21d88b2a1998e1d653bbd44bf3d06e47f610d3b3b2fed08f5d661624be2505", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8d21d88b2a1998e1d653bbd44bf3d06e47f610d3b3b2fed08f5d661624be2505", kill_on_drop: false }`
[INFO] [stdout] 8d21d88b2a1998e1d653bbd44bf3d06e47f610d3b3b2fed08f5d661624be2505
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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" "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" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0715fc874e3ef953f92cd72a4fac0e2d7e8b2de479be50e346e9d37c80c2985d
[INFO] running `Command { std: "docker" "start" "-a" "0715fc874e3ef953f92cd72a4fac0e2d7e8b2de479be50e346e9d37c80c2985d", kill_on_drop: false }`
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling ncurses v5.101.0
[INFO] [stderr]    Compiling pancurses v0.16.1
[INFO] [stderr]    Compiling utile_cli v0.3.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]    --> src/cli.rs:639:14
[INFO] [stdout]     |
[INFO] [stdout] 639 |           if (y < layers.len() - 1) {
[INFO] [stdout]     |              ^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]    --> src/cli.rs:644:14
[INFO] [stdout]     |
[INFO] [stdout] 644 |           if (y > 0) {
[INFO] [stdout]     |              ^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/cli.rs:494:11
[INFO] [stdout]     |
[INFO] [stdout] 494 |       _ | None => ()
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/cli.rs:493:23
[INFO] [stdout]     |
[INFO] [stdout] 493 |       Some(Key::Alpha(c)) => { self.raw_delete_prev(); },
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/cli.rs:513:23
[INFO] [stdout]     |
[INFO] [stdout] 513 |           if let Some(i) = r.get_content().pop() {
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/cli.rs:544:23
[INFO] [stdout]     |
[INFO] [stdout] 544 |           if let Some(i) = r.get_content().pop() {
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `pop`
[INFO] [stdout]    --> src/cli.rs:201:6
[INFO] [stdout]     |
[INFO] [stdout] 201 |   fn pop(&mut self) -> Option<Layer2D> {
[INFO] [stdout]     |      ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.10s
[INFO] running `Command { std: "docker" "inspect" "0715fc874e3ef953f92cd72a4fac0e2d7e8b2de479be50e346e9d37c80c2985d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0715fc874e3ef953f92cd72a4fac0e2d7e8b2de479be50e346e9d37c80c2985d", kill_on_drop: false }`
[INFO] [stdout] 0715fc874e3ef953f92cd72a4fac0e2d7e8b2de479be50e346e9d37c80c2985d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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" "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" "+beta-2021-08-01" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 51371e67167bfb1d61a97e72e385d9206bfc75705634ea13b01aee4d851a4c10
[INFO] running `Command { std: "docker" "start" "-a" "51371e67167bfb1d61a97e72e385d9206bfc75705634ea13b01aee4d851a4c10", kill_on_drop: false }`
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]    --> src/cli.rs:639:14
[INFO] [stdout]     |
[INFO] [stdout] 639 |           if (y < layers.len() - 1) {
[INFO] [stdout]     |              ^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]    --> src/cli.rs:644:14
[INFO] [stdout]     |
[INFO] [stdout] 644 |           if (y > 0) {
[INFO] [stdout]     |              ^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/cli.rs:494:11
[INFO] [stdout]     |
[INFO] [stdout] 494 |       _ | None => ()
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/cli.rs:493:23
[INFO] [stdout]     |
[INFO] [stdout] 493 |       Some(Key::Alpha(c)) => { self.raw_delete_prev(); },
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/cli.rs:513:23
[INFO] [stdout]     |
[INFO] [stdout] 513 |           if let Some(i) = r.get_content().pop() {
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/cli.rs:544:23
[INFO] [stdout]     |
[INFO] [stdout] 544 |           if let Some(i) = r.get_content().pop() {
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `pop`
[INFO] [stdout]    --> src/cli.rs:201:6
[INFO] [stdout]     |
[INFO] [stdout] 201 |   fn pop(&mut self) -> Option<Layer2D> {
[INFO] [stdout]     |      ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling utile_cli v0.3.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]    --> src/cli.rs:639:14
[INFO] [stdout]     |
[INFO] [stdout] 639 |           if (y < layers.len() - 1) {
[INFO] [stdout]     |              ^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]    --> src/cli.rs:644:14
[INFO] [stdout]     |
[INFO] [stdout] 644 |           if (y > 0) {
[INFO] [stdout]     |              ^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable pattern
[INFO] [stdout]    --> src/cli.rs:494:11
[INFO] [stdout]     |
[INFO] [stdout] 494 |       _ | None => ()
[INFO] [stdout]     |           ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `c`
[INFO] [stdout]    --> src/cli.rs:493:23
[INFO] [stdout]     |
[INFO] [stdout] 493 |       Some(Key::Alpha(c)) => { self.raw_delete_prev(); },
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/cli.rs:513:23
[INFO] [stdout]     |
[INFO] [stdout] 513 |           if let Some(i) = r.get_content().pop() {
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]    --> src/cli.rs:544:23
[INFO] [stdout]     |
[INFO] [stdout] 544 |           if let Some(i) = r.get_content().pop() {
[INFO] [stdout]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `l2d`
[INFO] [stdout]   --> src/lib.rs:71:9
[INFO] [stdout]    |
[INFO] [stdout] 71 |     let l2d = t.add_layer2d(l2d);
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_l2d`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/lib.rs:81:9
[INFO] [stdout]    |
[INFO] [stdout] 81 |     let mut behindl2d = Layer2D::new(0, 0, 4, 4, behindl);
[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/lib.rs:85:9
[INFO] [stdout]    |
[INFO] [stdout] 85 |     let mut frontl2d = Layer2D::new(0, 0, 2, 2, frontl);
[INFO] [stdout]    |         ----^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `pop`
[INFO] [stdout]    --> src/cli.rs:201:6
[INFO] [stdout]     |
[INFO] [stdout] 201 |   fn pop(&mut self) -> Option<Layer2D> {
[INFO] [stdout]     |      ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 10 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.76s
[INFO] running `Command { std: "docker" "inspect" "51371e67167bfb1d61a97e72e385d9206bfc75705634ea13b01aee4d851a4c10", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "51371e67167bfb1d61a97e72e385d9206bfc75705634ea13b01aee4d851a4c10", kill_on_drop: false }`
[INFO] [stdout] 51371e67167bfb1d61a97e72e385d9206bfc75705634ea13b01aee4d851a4c10
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-93/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" "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" "+beta-2021-08-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] e5e4f9965a767977ba1b448c4fe08b2cd56a82efb338185a2c3fd22195fcbf97
[INFO] running `Command { std: "docker" "start" "-a" "e5e4f9965a767977ba1b448c4fe08b2cd56a82efb338185a2c3fd22195fcbf97", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]    --> src/cli.rs:639:14
[INFO] [stderr]     |
[INFO] [stderr] 639 |           if (y < layers.len() - 1) {
[INFO] [stderr]     |              ^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]    --> src/cli.rs:644:14
[INFO] [stderr]     |
[INFO] [stderr] 644 |           if (y > 0) {
[INFO] [stderr]     |              ^^^^^^^ help: remove these parentheses
[INFO] [stderr] 
[INFO] [stderr] warning: unreachable pattern
[INFO] [stderr]    --> src/cli.rs:494:11
[INFO] [stderr]     |
[INFO] [stderr] 494 |       _ | None => ()
[INFO] [stderr]     |           ^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unreachable_patterns)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `c`
[INFO] [stderr]    --> src/cli.rs:493:23
[INFO] [stderr]     |
[INFO] [stderr] 493 |       Some(Key::Alpha(c)) => { self.raw_delete_prev(); },
[INFO] [stderr]     |                       ^ help: if this is intentional, prefix it with an underscore: `_c`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]    --> src/cli.rs:513:23
[INFO] [stderr]     |
[INFO] [stderr] 513 |           if let Some(i) = r.get_content().pop() {
[INFO] [stderr]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]    --> src/cli.rs:544:23
[INFO] [stderr]     |
[INFO] [stderr] 544 |           if let Some(i) = r.get_content().pop() {
[INFO] [stderr]     |                       ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stderr] 
[INFO] [stderr] warning: associated function is never used: `pop`
[INFO] [stderr]    --> src/cli.rs:201:6
[INFO] [stderr]     |
[INFO] [stderr] 201 |   fn pop(&mut self) -> Option<Layer2D> {
[INFO] [stderr]     |      ^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `l2d`
[INFO] [stderr]   --> src/lib.rs:71:9
[INFO] [stderr]    |
[INFO] [stderr] 71 |     let l2d = t.add_layer2d(l2d);
[INFO] [stderr]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_l2d`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/lib.rs:81:9
[INFO] [stderr]    |
[INFO] [stderr] 81 |     let mut behindl2d = Layer2D::new(0, 0, 4, 4, behindl);
[INFO] [stderr]    |         ----^^^^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/lib.rs:85:9
[INFO] [stderr]    |
[INFO] [stderr] 85 |     let mut frontl2d = Layer2D::new(0, 0, 2, 2, frontl);
[INFO] [stderr]    |         ----^^^^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: `utile_cli` (lib) generated 7 warnings
[INFO] [stderr] warning: `utile_cli` (lib test) generated 10 warnings (7 duplicates)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.09s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/utile_cli-5f4569720dc5b81e)
[INFO] [stdout] 
[INFO] [stdout] running 10 tests
[INFO] [stdout] test tests::input ... ok
[INFO] [stdout] test tests::layer2d ... ok
[INFO] [stdout] test tests::mask ... ok
[INFO] [stdout] test tests::layer_arr ... ok
[INFO] [stdout] test tests::output ... ok
[INFO] [stdout] test tests::term ... ok
[INFO] [stdout] test tests::yes_no ... ok
[INFO] [stderr] Error opening terminal: unknown.
[INFO] [stderr] error: test failed, to rerun pass '--lib'
[INFO] running `Command { std: "docker" "inspect" "e5e4f9965a767977ba1b448c4fe08b2cd56a82efb338185a2c3fd22195fcbf97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5e4f9965a767977ba1b448c4fe08b2cd56a82efb338185a2c3fd22195fcbf97", kill_on_drop: false }`
[INFO] [stdout] e5e4f9965a767977ba1b448c4fe08b2cd56a82efb338185a2c3fd22195fcbf97
