[INFO] cloning repository https://github.com/halcyon/rust_tut
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/halcyon/rust_tut" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhalcyon%2Frust_tut", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhalcyon%2Frust_tut'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 558bf4aae326605a6934155e7faf29e8747627d9
[INFO] testing halcyon/rust_tut against 1.60.0 for beta-1.61-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fhalcyon%2Frust_tut" "/workspace/builds/worker-23/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-23/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/halcyon/rust_tut on toolchain 1.60.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/halcyon/rust_tut
[INFO] finished tweaking git repo https://github.com/halcyon/rust_tut
[INFO] tweaked toml for git repo https://github.com/halcyon/rust_tut written to /workspace/builds/worker-23/source/Cargo.toml
[INFO] crate git repo https://github.com/halcyon/rust_tut already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.60.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2caa06bd1898e0ebfcf1670ef3e4086e0d66ee26ea0cbf45d41e06b6c26d0368
[INFO] running `Command { std: "docker" "start" "-a" "2caa06bd1898e0ebfcf1670ef3e4086e0d66ee26ea0cbf45d41e06b6c26d0368", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2caa06bd1898e0ebfcf1670ef3e4086e0d66ee26ea0cbf45d41e06b6c26d0368", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2caa06bd1898e0ebfcf1670ef3e4086e0d66ee26ea0cbf45d41e06b6c26d0368", kill_on_drop: false }`
[INFO] [stdout] 2caa06bd1898e0ebfcf1670ef3e4086e0d66ee26ea0cbf45d41e06b6c26d0368
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3ecf11fc6530fe63f9c6cca30152d5496ad60a3ea2fe7d8baf2eb4783713cfff
[INFO] running `Command { std: "docker" "start" "-a" "3ecf11fc6530fe63f9c6cca30152d5496ad60a3ea2fe7d8baf2eb4783713cfff", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rust_tut v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `u16`, `u32`, `u64`, `u8`
[INFO] [stdout]  --> src/main.rs:1:30
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{i8, i16, i32, i64, u8, u16, u32, u64, isize, usize, f32, f64};
[INFO] [stdout]   |                              ^^  ^^^  ^^^  ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:62:8
[INFO] [stdout]    |
[INFO] [stdout] 62 |     if (age_old == 5) {
[INFO] [stdout]    |        ^            ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 62 -     if (age_old == 5) {
[INFO] [stdout] 62 +     if age_old == 5 {
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:78:23
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let can_vote = if (age_old >= 18) { true } else { false };
[INFO] [stdout]    |                       ^             ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 78 -     let can_vote = if (age_old >= 18) { true } else { false };
[INFO] [stdout] 78 +     let can_vote = if age_old >= 18 { true } else { false };
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:85:12
[INFO] [stdout]    |
[INFO] [stdout] 85 |         if ((x % 2) == 0) {
[INFO] [stdout]    |            ^            ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 85 -         if ((x % 2) == 0) {
[INFO] [stdout] 85 +         if (x % 2) == 0 {
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:90:12
[INFO] [stdout]    |
[INFO] [stdout] 90 |         if (x > 10) {
[INFO] [stdout]    |            ^      ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 90 -         if (x > 10) {
[INFO] [stdout] 90 +         if x > 10 {
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let num = 10;
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f_name`
[INFO] [stdout]   --> src/main.rs:34:10
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (f_name, l_name) = ("Derek", "Banas");
[INFO] [stdout]    |          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_f_name`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `l_name`
[INFO] [stdout]   --> src/main.rs:34:18
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (f_name, l_name) = ("Derek", "Banas");
[INFO] [stdout]    |                  ^^^^^^ help: if this is intentional, prefix it with an underscore: `_l_name`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `count`
[INFO] [stdout]    --> src/main.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 116 |     let count = rand_string.chars().count();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_count`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let mut age: i32 = 40;
[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/main.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let mut neg_4 = -4i32;
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.23s
[INFO] running `Command { std: "docker" "inspect" "3ecf11fc6530fe63f9c6cca30152d5496ad60a3ea2fe7d8baf2eb4783713cfff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3ecf11fc6530fe63f9c6cca30152d5496ad60a3ea2fe7d8baf2eb4783713cfff", kill_on_drop: false }`
[INFO] [stdout] 3ecf11fc6530fe63f9c6cca30152d5496ad60a3ea2fe7d8baf2eb4783713cfff
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 47e4a43dfb7a9ea7aa6d1c894824ec18b5a8b435d0ce28a79c39099d5192feff
[INFO] running `Command { std: "docker" "start" "-a" "47e4a43dfb7a9ea7aa6d1c894824ec18b5a8b435d0ce28a79c39099d5192feff", kill_on_drop: false }`
[INFO] [stderr]    Compiling rust_tut v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused imports: `u16`, `u32`, `u64`, `u8`
[INFO] [stdout]  --> src/main.rs:1:30
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::{i8, i16, i32, i64, u8, u16, u32, u64, isize, usize, f32, f64};
[INFO] [stdout]   |                              ^^  ^^^  ^^^  ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:62:8
[INFO] [stdout]    |
[INFO] [stdout] 62 |     if (age_old == 5) {
[INFO] [stdout]    |        ^            ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 62 -     if (age_old == 5) {
[INFO] [stdout] 62 +     if age_old == 5 {
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:78:23
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let can_vote = if (age_old >= 18) { true } else { false };
[INFO] [stdout]    |                       ^             ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 78 -     let can_vote = if (age_old >= 18) { true } else { false };
[INFO] [stdout] 78 +     let can_vote = if age_old >= 18 { true } else { false };
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:85:12
[INFO] [stdout]    |
[INFO] [stdout] 85 |         if ((x % 2) == 0) {
[INFO] [stdout]    |            ^            ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 85 -         if ((x % 2) == 0) {
[INFO] [stdout] 85 +         if (x % 2) == 0 {
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around `if` condition
[INFO] [stdout]   --> src/main.rs:90:12
[INFO] [stdout]    |
[INFO] [stdout] 90 |         if (x > 10) {
[INFO] [stdout]    |            ^      ^
[INFO] [stdout]    |
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 90 -         if (x > 10) {
[INFO] [stdout] 90 +         if x > 10 {
[INFO] [stdout]    | 
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]  --> src/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let num = 10;
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `f_name`
[INFO] [stdout]   --> src/main.rs:34:10
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (f_name, l_name) = ("Derek", "Banas");
[INFO] [stdout]    |          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_f_name`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `l_name`
[INFO] [stdout]   --> src/main.rs:34:18
[INFO] [stdout]    |
[INFO] [stdout] 34 |     let (f_name, l_name) = ("Derek", "Banas");
[INFO] [stdout]    |                  ^^^^^^ help: if this is intentional, prefix it with an underscore: `_l_name`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `count`
[INFO] [stdout]    --> src/main.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 116 |     let count = rand_string.chars().count();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_count`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:10:9
[INFO] [stdout]    |
[INFO] [stdout] 10 |     let mut age: i32 = 40;
[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/main.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |     let mut neg_4 = -4i32;
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 11 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.34s
[INFO] running `Command { std: "docker" "inspect" "47e4a43dfb7a9ea7aa6d1c894824ec18b5a8b435d0ce28a79c39099d5192feff", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "47e4a43dfb7a9ea7aa6d1c894824ec18b5a8b435d0ce28a79c39099d5192feff", kill_on_drop: false }`
[INFO] [stdout] 47e4a43dfb7a9ea7aa6d1c894824ec18b5a8b435d0ce28a79c39099d5192feff
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-23/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:b0c94ce3c1162fcb8e57cac5b65ec2f72eabb1eebea4fcc35e269e823f681646" "/opt/rustwide/cargo-home/bin/cargo" "+1.60.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 2654a58877a7e43e5cdb73988e320f6ffdc776e933a284f670ea3fac38a87571
[INFO] running `Command { std: "docker" "start" "-a" "2654a58877a7e43e5cdb73988e320f6ffdc776e933a284f670ea3fac38a87571", kill_on_drop: false }`
[INFO] [stderr] warning: unused imports: `u16`, `u32`, `u64`, `u8`
[INFO] [stderr]  --> src/main.rs:1:30
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::{i8, i16, i32, i64, u8, u16, u32, u64, isize, usize, f32, f64};
[INFO] [stderr]   |                              ^^  ^^^  ^^^  ^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]   --> src/main.rs:62:8
[INFO] [stderr]    |
[INFO] [stderr] 62 |     if (age_old == 5) {
[INFO] [stderr]    |        ^            ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr] 62 -     if (age_old == 5) {
[INFO] [stderr] 62 +     if age_old == 5 {
[INFO] [stderr]    | 
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]   --> src/main.rs:78:23
[INFO] [stderr]    |
[INFO] [stderr] 78 |     let can_vote = if (age_old >= 18) { true } else { false };
[INFO] [stderr]    |                       ^             ^
[INFO] [stderr]    |
[INFO] [stderr] help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr] 78 -     let can_vote = if (age_old >= 18) { true } else { false };
[INFO] [stderr] 78 +     let can_vote = if age_old >= 18 { true } else { false };
[INFO] [stderr]    | 
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]   --> src/main.rs:85:12
[INFO] [stderr]    |
[INFO] [stderr] 85 |         if ((x % 2) == 0) {
[INFO] [stderr]    |            ^            ^
[INFO] [stderr]    |
[INFO] [stderr] help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr] 85 -         if ((x % 2) == 0) {
[INFO] [stderr] 85 +         if (x % 2) == 0 {
[INFO] [stderr]    | 
[INFO] [stderr] 
[INFO] [stderr] warning: unnecessary parentheses around `if` condition
[INFO] [stderr]   --> src/main.rs:90:12
[INFO] [stderr]    |
[INFO] [stderr] 90 |         if (x > 10) {
[INFO] [stderr]    |            ^      ^
[INFO] [stderr]    |
[INFO] [stderr] help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr] 90 -         if (x > 10) {
[INFO] [stderr] 90 +         if x > 10 {
[INFO] [stderr]    | 
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `num`
[INFO] [stderr]  --> src/main.rs:8:9
[INFO] [stderr]   |
[INFO] [stderr] 8 |     let num = 10;
[INFO] [stderr]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `f_name`
[INFO] [stderr]   --> src/main.rs:34:10
[INFO] [stderr]    |
[INFO] [stderr] 34 |     let (f_name, l_name) = ("Derek", "Banas");
[INFO] [stderr]    |          ^^^^^^ help: if this is intentional, prefix it with an underscore: `_f_name`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `l_name`
[INFO] [stderr]   --> src/main.rs:34:18
[INFO] [stderr]    |
[INFO] [stderr] 34 |     let (f_name, l_name) = ("Derek", "Banas");
[INFO] [stderr]    |                  ^^^^^^ help: if this is intentional, prefix it with an underscore: `_l_name`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `count`
[INFO] [stderr]    --> src/main.rs:116:9
[INFO] [stderr]     |
[INFO] [stderr] 116 |     let count = rand_string.chars().count();
[INFO] [stderr]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_count`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:10:9
[INFO] [stderr]    |
[INFO] [stderr] 10 |     let mut age: i32 = 40;
[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/main.rs:52:9
[INFO] [stderr]    |
[INFO] [stderr] 52 |     let mut neg_4 = -4i32;
[INFO] [stderr]    |         ----^^^^^
[INFO] [stderr]    |         |
[INFO] [stderr]    |         help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: `rust_tut` (bin "rust_tut" test) generated 11 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/rust_tut-a2d6f99e4e937516)
[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" "2654a58877a7e43e5cdb73988e320f6ffdc776e933a284f670ea3fac38a87571", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2654a58877a7e43e5cdb73988e320f6ffdc776e933a284f670ea3fac38a87571", kill_on_drop: false }`
[INFO] [stdout] 2654a58877a7e43e5cdb73988e320f6ffdc776e933a284f670ea3fac38a87571