[INFO] cloning repository https://github.com/AnthonyP4312/i3-alt-tab
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/AnthonyP4312/i3-alt-tab" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAnthonyP4312%2Fi3-alt-tab", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAnthonyP4312%2Fi3-alt-tab'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 64efd56944d26cce816fc0e4b7cefb9b5e201b0e
[INFO] testing AnthonyP4312/i3-alt-tab against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAnthonyP4312%2Fi3-alt-tab" "/workspace/builds/worker-112/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-112/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/AnthonyP4312/i3-alt-tab on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/AnthonyP4312/i3-alt-tab
[INFO] finished tweaking git repo https://github.com/AnthonyP4312/i3-alt-tab
[INFO] tweaked toml for git repo https://github.com/AnthonyP4312/i3-alt-tab written to /workspace/builds/worker-112/source/Cargo.toml
[INFO] crate git repo https://github.com/AnthonyP4312/i3-alt-tab already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "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-112/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/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" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 14aba5b11ac8857b3c5233dd075eea865200ce3328f93e27eb47d6eb9d72b251
[INFO] running `Command { std: "docker" "start" "-a" "14aba5b11ac8857b3c5233dd075eea865200ce3328f93e27eb47d6eb9d72b251", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "14aba5b11ac8857b3c5233dd075eea865200ce3328f93e27eb47d6eb9d72b251", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "14aba5b11ac8857b3c5233dd075eea865200ce3328f93e27eb47d6eb9d72b251", kill_on_drop: false }`
[INFO] [stdout] 14aba5b11ac8857b3c5233dd075eea865200ce3328f93e27eb47d6eb9d72b251
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/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" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4da7bb656406af7b7ddaf170577e2da4ab4d3a157f3df2e9a687bf670be2e444
[INFO] running `Command { std: "docker" "start" "-a" "4da7bb656406af7b7ddaf170577e2da4ab4d3a157f3df2e9a687bf670be2e444", kill_on_drop: false }`
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling serde v1.0.66
[INFO] [stderr]    Compiling itoa v0.4.1
[INFO] [stderr]    Compiling proc-macro2 v0.4.6
[INFO] [stderr]    Compiling quote v0.6.3
[INFO] [stderr]    Compiling syn v0.14.2
[INFO] [stderr]    Compiling serde_derive v1.0.66
[INFO] [stderr]    Compiling serde_json v1.0.21
[INFO] [stderr]    Compiling alt_tabber v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:39:5
[INFO] [stdout]    |
[INFO] [stdout] 39 | /     Command::new("i3-msg")
[INFO] [stdout] 40 | |         .arg(format!("[con_id={}] focus", next.id))
[INFO] [stdout] 41 | |         .output();
[INFO] [stdout]    | |__________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 15.76s
[INFO] running `Command { std: "docker" "inspect" "4da7bb656406af7b7ddaf170577e2da4ab4d3a157f3df2e9a687bf670be2e444", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4da7bb656406af7b7ddaf170577e2da4ab4d3a157f3df2e9a687bf670be2e444", kill_on_drop: false }`
[INFO] [stdout] 4da7bb656406af7b7ddaf170577e2da4ab4d3a157f3df2e9a687bf670be2e444
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/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" "+beta-2021-09-08" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 49e3b7022042b320cbd5388227ef011d88c3c987925d893a6d915eb8deb4e5d8
[INFO] running `Command { std: "docker" "start" "-a" "49e3b7022042b320cbd5388227ef011d88c3c987925d893a6d915eb8deb4e5d8", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling alt_tabber v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `child_c`
[INFO] [stdout]   --> src/main.rs:85:13
[INFO] [stdout]    |
[INFO] [stdout] 85 |         let child_c = Node {
[INFO] [stdout]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_child_c`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `node_with_children`
[INFO] [stdout]   --> src/main.rs:89:13
[INFO] [stdout]    |
[INFO] [stdout] 89 |         let node_with_children = Node {
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_node_with_children`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `setup`
[INFO] [stdout]   --> src/main.rs:67:8
[INFO] [stdout]    |
[INFO] [stdout] 67 |     fn setup() {
[INFO] [stdout]    |        ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/main.rs:39:5
[INFO] [stdout]    |
[INFO] [stdout] 39 | /     Command::new("i3-msg")
[INFO] [stdout] 40 | |         .arg(format!("[con_id={}] focus", next.id))
[INFO] [stdout] 41 | |         .output();
[INFO] [stdout]    | |__________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 4.31s
[INFO] running `Command { std: "docker" "inspect" "49e3b7022042b320cbd5388227ef011d88c3c987925d893a6d915eb8deb4e5d8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "49e3b7022042b320cbd5388227ef011d88c3c987925d893a6d915eb8deb4e5d8", kill_on_drop: false }`
[INFO] [stdout] 49e3b7022042b320cbd5388227ef011d88c3c987925d893a6d915eb8deb4e5d8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-112/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" "+beta-2021-09-08" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] afe9e39870b1acefca5bfd9b54ffe2783780b4990c75b936b4bc474fdf79ecb3
[INFO] running `Command { std: "docker" "start" "-a" "afe9e39870b1acefca5bfd9b54ffe2783780b4990c75b936b4bc474fdf79ecb3", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr] warning: unused variable: `child_c`
[INFO] [stderr]   --> src/main.rs:85:13
[INFO] [stderr]    |
[INFO] [stderr] 85 |         let child_c = Node {
[INFO] [stderr]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_child_c`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `node_with_children`
[INFO] [stderr]   --> src/main.rs:89:13
[INFO] [stderr]    |
[INFO] [stderr] 89 |         let node_with_children = Node {
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_node_with_children`
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `setup`
[INFO] [stderr]   --> src/main.rs:67:8
[INFO] [stderr]    |
[INFO] [stderr] 67 |     fn setup() {
[INFO] [stderr]    |        ^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/main.rs:39:5
[INFO] [stderr]    |
[INFO] [stderr] 39 | /     Command::new("i3-msg")
[INFO] [stderr] 40 | |         .arg(format!("[con_id={}] focus", next.id))
[INFO] [stderr] 41 | |         .output();
[INFO] [stderr]    | |__________________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] 
[INFO] [stderr] warning: `alt_tabber` (bin "alt_tabber" test) generated 4 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.55s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/alt_tabber-d53b1f419614eeb6)
[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] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/alt_tabber-ba54f5b706049e4b)
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test test_flatten::flattens ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests alt_tabber
[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" "afe9e39870b1acefca5bfd9b54ffe2783780b4990c75b936b4bc474fdf79ecb3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "afe9e39870b1acefca5bfd9b54ffe2783780b4990c75b936b4bc474fdf79ecb3", kill_on_drop: false }`
[INFO] [stdout] afe9e39870b1acefca5bfd9b54ffe2783780b4990c75b936b4bc474fdf79ecb3