[INFO] cloning repository https://github.com/juliob29/Rust-Doubly-Linked-List
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/juliob29/Rust-Doubly-Linked-List" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjuliob29%2FRust-Doubly-Linked-List", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjuliob29%2FRust-Doubly-Linked-List'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f2b03c65ec30a503bc26bdd76001aa12696e550a
[INFO] testing juliob29/Rust-Doubly-Linked-List against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjuliob29%2FRust-Doubly-Linked-List" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/juliob29/Rust-Doubly-Linked-List on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/juliob29/Rust-Doubly-Linked-List
[INFO] finished tweaking git repo https://github.com/juliob29/Rust-Doubly-Linked-List
[INFO] tweaked toml for git repo https://github.com/juliob29/Rust-Doubly-Linked-List written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/juliob29/Rust-Doubly-Linked-List already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 36cb3679fac297d867ea1d92b7884e6602c3810503140437752d22b1b1d0cd89
[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" "36cb3679fac297d867ea1d92b7884e6602c3810503140437752d22b1b1d0cd89", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "36cb3679fac297d867ea1d92b7884e6602c3810503140437752d22b1b1d0cd89", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "36cb3679fac297d867ea1d92b7884e6602c3810503140437752d22b1b1d0cd89", kill_on_drop: false }`
[INFO] [stdout] 36cb3679fac297d867ea1d92b7884e6602c3810503140437752d22b1b1d0cd89
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 57c2d17d519413890a27de2fe634b409d6f23f9db8b064d15b2752aae118816c
[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" "57c2d17d519413890a27de2fe634b409d6f23f9db8b064d15b2752aae118816c", kill_on_drop: false }`
[INFO] [stderr]    Compiling doubly-linked-list v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `fmt::Display`
[INFO] [stdout]  --> src/main.rs:6:26
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::{cell::RefCell, fmt::Display, rc::Rc}; 
[INFO] [stdout]   |                          ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:29:11
[INFO] [stdout]    |
[INFO] [stdout] 29 |       let mut new_node = Rc::new(RefCell::new(Node{
[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: method `printList` should have a snake case name
[INFO] [stdout]   --> src/main.rs:48:6
[INFO] [stdout]    |
[INFO] [stdout] 48 |   fn printList(&self) {
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to snake case: `print_list`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `printBack` should have a snake case name
[INFO] [stdout]   --> src/main.rs:58:6
[INFO] [stdout]    |
[INFO] [stdout] 58 |   fn printBack(&self) {
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to snake case: `print_back`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.72s
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "57c2d17d519413890a27de2fe634b409d6f23f9db8b064d15b2752aae118816c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "57c2d17d519413890a27de2fe634b409d6f23f9db8b064d15b2752aae118816c", kill_on_drop: false }`
[INFO] [stdout] 57c2d17d519413890a27de2fe634b409d6f23f9db8b064d15b2752aae118816c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 130ee5930542e026d3bf0c6636e113a47beb17fa84dfe962774f2455fba73a97
[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" "130ee5930542e026d3bf0c6636e113a47beb17fa84dfe962774f2455fba73a97", kill_on_drop: false }`
[INFO] [stderr]    Compiling doubly-linked-list v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `fmt::Display`
[INFO] [stdout]  --> src/main.rs:6:26
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::{cell::RefCell, fmt::Display, rc::Rc}; 
[INFO] [stdout]   |                          ^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:29:11
[INFO] [stdout]    |
[INFO] [stdout] 29 |       let mut new_node = Rc::new(RefCell::new(Node{
[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: method `printList` should have a snake case name
[INFO] [stdout]   --> src/main.rs:48:6
[INFO] [stdout]    |
[INFO] [stdout] 48 |   fn printList(&self) {
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to snake case: `print_list`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `printBack` should have a snake case name
[INFO] [stdout]   --> src/main.rs:58:6
[INFO] [stdout]    |
[INFO] [stdout] 58 |   fn printBack(&self) {
[INFO] [stdout]    |      ^^^^^^^^^ help: convert the identifier to snake case: `print_back`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.72s
[INFO] running `Command { std: "docker" "inspect" "130ee5930542e026d3bf0c6636e113a47beb17fa84dfe962774f2455fba73a97", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "130ee5930542e026d3bf0c6636e113a47beb17fa84dfe962774f2455fba73a97", kill_on_drop: false }`
[INFO] [stdout] 130ee5930542e026d3bf0c6636e113a47beb17fa84dfe962774f2455fba73a97
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 073ecef6d32487c0e68a1b85e61c383a355981ee8ab8826131310091e6949b6b
[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" "073ecef6d32487c0e68a1b85e61c383a355981ee8ab8826131310091e6949b6b", kill_on_drop: false }`
[INFO] [stderr] warning: unused import: `fmt::Display`
[INFO] [stderr]  --> src/main.rs:6:26
[INFO] [stderr]   |
[INFO] [stderr] 6 | use std::{cell::RefCell, fmt::Display, rc::Rc}; 
[INFO] [stderr]   |                          ^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:29:11
[INFO] [stderr]    |
[INFO] [stderr] 29 |       let mut new_node = Rc::new(RefCell::new(Node{
[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: method `printList` should have a snake case name
[INFO] [stderr]   --> src/main.rs:48:6
[INFO] [stderr]    |
[INFO] [stderr] 48 |   fn printList(&self) {
[INFO] [stderr]    |      ^^^^^^^^^ help: convert the identifier to snake case: `print_list`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(non_snake_case)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method `printBack` should have a snake case name
[INFO] [stderr]   --> src/main.rs:58:6
[INFO] [stderr]    |
[INFO] [stderr] 58 |   fn printBack(&self) {
[INFO] [stderr]    |      ^^^^^^^^^ help: convert the identifier to snake case: `print_back`
[INFO] [stderr] 
[INFO] [stderr] warning: `doubly-linked-list` (bin "doubly-linked-list" test) generated 4 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/doubly_linked_list-4295bbadaa931af6)
[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" "073ecef6d32487c0e68a1b85e61c383a355981ee8ab8826131310091e6949b6b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "073ecef6d32487c0e68a1b85e61c383a355981ee8ab8826131310091e6949b6b", kill_on_drop: false }`
[INFO] [stdout] 073ecef6d32487c0e68a1b85e61c383a355981ee8ab8826131310091e6949b6b