[INFO] fetching crate syntactic_heap 0.3.1...
[INFO] testing syntactic_heap-0.3.1 against master#caccb4d0368bd918ef6668af8e13834d07040417 for pr-146098-1
[INFO] extracting crate syntactic_heap 0.3.1 into /workspace/builds/worker-7-tc1/source
[INFO] started tweaking crates.io crate syntactic_heap 0.3.1
[INFO] finished tweaking crates.io crate syntactic_heap 0.3.1
[INFO] tweaked toml for crates.io crate syntactic_heap 0.3.1 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate syntactic_heap 0.3.1 on toolchain caccb4d0368bd918ef6668af8e13834d07040417
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0c77d02b86e7b0debfefd045ae64897879cd4cadf4f1a1c22d169aad2099f46d
[INFO] running `Command { std: "docker" "start" "-a" "0c77d02b86e7b0debfefd045ae64897879cd4cadf4f1a1c22d169aad2099f46d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0c77d02b86e7b0debfefd045ae64897879cd4cadf4f1a1c22d169aad2099f46d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0c77d02b86e7b0debfefd045ae64897879cd4cadf4f1a1c22d169aad2099f46d", kill_on_drop: false }`
[INFO] [stdout] 0c77d02b86e7b0debfefd045ae64897879cd4cadf4f1a1c22d169aad2099f46d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b576394607ae34161dd4f833feea7610e30a5cfeb14c5007bb2edc31d355b953
[INFO] running `Command { std: "docker" "start" "-a" "b576394607ae34161dd4f833feea7610e30a5cfeb14c5007bb2edc31d355b953", kill_on_drop: false }`
[INFO] [stderr]    Compiling syntactic_heap v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:72:2
[INFO] [stdout]    |
[INFO] [stdout] 72 |     write!(f,"[");
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let _ = write!(f,"[");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:74:18
[INFO] [stdout]    |
[INFO] [stdout] 74 |         if !first { write!(f,","); }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 74 |         if !first { let _ = write!(f,","); }
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:76:6
[INFO] [stdout]    |
[INFO] [stdout] 76 |         write!(f,"{}",item);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let _ = write!(f,"{}",item);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:86:2
[INFO] [stdout]    |
[INFO] [stdout] 86 |     write!(f,"[");
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let _ = write!(f,"[");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:88:18
[INFO] [stdout]    |
[INFO] [stdout] 88 |         if !first { write!(f,","); }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 88 |         if !first { let _ = write!(f,","); }
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:90:6
[INFO] [stdout]    |
[INFO] [stdout] 90 |         write!(f,"{:?}",item);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 90 |         let _ = write!(f,"{:?}",item);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.15s
[INFO] running `Command { std: "docker" "inspect" "b576394607ae34161dd4f833feea7610e30a5cfeb14c5007bb2edc31d355b953", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b576394607ae34161dd4f833feea7610e30a5cfeb14c5007bb2edc31d355b953", kill_on_drop: false }`
[INFO] [stdout] b576394607ae34161dd4f833feea7610e30a5cfeb14c5007bb2edc31d355b953
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e4f9501a02350963274c7070480a8856b77e3116dc6d6c5080957b44d3f7ca20
[INFO] running `Command { std: "docker" "start" "-a" "e4f9501a02350963274c7070480a8856b77e3116dc6d6c5080957b44d3f7ca20", kill_on_drop: false }`
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:72:2
[INFO] [stdout]    |
[INFO] [stdout] 72 |     write!(f,"[");
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let _ = write!(f,"[");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:74:18
[INFO] [stdout]    |
[INFO] [stdout] 74 |         if !first { write!(f,","); }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 74 |         if !first { let _ = write!(f,","); }
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:76:6
[INFO] [stdout]    |
[INFO] [stdout] 76 |         write!(f,"{}",item);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let _ = write!(f,"{}",item);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:86:2
[INFO] [stdout]    |
[INFO] [stdout] 86 |     write!(f,"[");
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let _ = write!(f,"[");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:88:18
[INFO] [stdout]    |
[INFO] [stdout] 88 |         if !first { write!(f,","); }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 88 |         if !first { let _ = write!(f,","); }
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:90:6
[INFO] [stdout]    |
[INFO] [stdout] 90 |         write!(f,"{:?}",item);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 90 |         let _ = write!(f,"{:?}",item);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling syntactic_heap v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:72:2
[INFO] [stdout]    |
[INFO] [stdout] 72 |     write!(f,"[");
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |     let _ = write!(f,"[");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:74:18
[INFO] [stdout]    |
[INFO] [stdout] 74 |         if !first { write!(f,","); }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 74 |         if !first { let _ = write!(f,","); }
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:76:6
[INFO] [stdout]    |
[INFO] [stdout] 76 |         write!(f,"{}",item);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let _ = write!(f,"{}",item);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:86:2
[INFO] [stdout]    |
[INFO] [stdout] 86 |     write!(f,"[");
[INFO] [stdout]    |     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 86 |     let _ = write!(f,"[");
[INFO] [stdout]    |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:88:18
[INFO] [stdout]    |
[INFO] [stdout] 88 |         if !first { write!(f,","); }
[INFO] [stdout]    |                     ^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 88 |         if !first { let _ = write!(f,","); }
[INFO] [stdout]    |                     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/lib.rs:90:6
[INFO] [stdout]    |
[INFO] [stdout] 90 |         write!(f,"{:?}",item);
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 90 |         let _ = write!(f,"{:?}",item);
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.56s
[INFO] running `Command { std: "docker" "inspect" "e4f9501a02350963274c7070480a8856b77e3116dc6d6c5080957b44d3f7ca20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e4f9501a02350963274c7070480a8856b77e3116dc6d6c5080957b44d3f7ca20", kill_on_drop: false }`
[INFO] [stdout] e4f9501a02350963274c7070480a8856b77e3116dc6d6c5080957b44d3f7ca20
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+caccb4d0368bd918ef6668af8e13834d07040417" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 9dbd714f69a58672d533755f1e829afc820f739968f5fddbd1d4a59898aba41b
[INFO] running `Command { std: "docker" "start" "-a" "9dbd714f69a58672d533755f1e829afc820f739968f5fddbd1d4a59898aba41b", kill_on_drop: false }`
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/lib.rs:72:2
[INFO] [stderr]    |
[INFO] [stderr] 72 |     write!(f,"[");
[INFO] [stderr]    |     ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` (part of `#[warn(unused)]`) on by default
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 72 |     let _ = write!(f,"[");
[INFO] [stderr]    |     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/lib.rs:74:18
[INFO] [stderr]    |
[INFO] [stderr] 74 |         if !first { write!(f,","); }
[INFO] [stderr]    |                     ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 74 |         if !first { let _ = write!(f,","); }
[INFO] [stderr]    |                     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/lib.rs:76:6
[INFO] [stderr]    |
[INFO] [stderr] 76 |         write!(f,"{}",item);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 76 |         let _ = write!(f,"{}",item);
[INFO] [stderr]    |         +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/lib.rs:86:2
[INFO] [stderr]    |
[INFO] [stderr] 86 |     write!(f,"[");
[INFO] [stderr]    |     ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 86 |     let _ = write!(f,"[");
[INFO] [stderr]    |     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/lib.rs:88:18
[INFO] [stderr]    |
[INFO] [stderr] 88 |         if !first { write!(f,","); }
[INFO] [stderr]    |                     ^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 88 |         if !first { let _ = write!(f,","); }
[INFO] [stderr]    |                     +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: unused `Result` that must be used
[INFO] [stderr]   --> src/lib.rs:90:6
[INFO] [stderr]    |
[INFO] [stderr] 90 |         write!(f,"{:?}",item);
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 90 |         let _ = write!(f,"{:?}",item);
[INFO] [stderr]    |         +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: `syntactic_heap` (lib) generated 6 warnings
[INFO] [stderr] warning: `syntactic_heap` (lib test) generated 6 warnings (6 duplicates)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.07s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/syntactic_heap-0fc74e6190709721)
[INFO] [stderr]      Running tests/lambda_calculus.rs (/opt/rustwide/target/debug/deps/lambda_calculus-af6750a449480a76)
[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] [stdout] 
[INFO] [stdout] running 8 tests
[INFO] [stderr]    Doc-tests syntactic_heap
[INFO] [stdout] test test_clone_01 ... ok
[INFO] [stdout] test test_iter_01 ... ok
[INFO] [stdout] test test_clone_02 ... ok
[INFO] [stdout] test test_iter_02 ... ok
[INFO] [stdout] test test_heap_01 ... ok
[INFO] [stdout] test test_heap_03 ... ok
[INFO] [stdout] test test_iter_03 ... ok
[INFO] [stdout] test test_heap_02 ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 8 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[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" "9dbd714f69a58672d533755f1e829afc820f739968f5fddbd1d4a59898aba41b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9dbd714f69a58672d533755f1e829afc820f739968f5fddbd1d4a59898aba41b", kill_on_drop: false }`
[INFO] [stdout] 9dbd714f69a58672d533755f1e829afc820f739968f5fddbd1d4a59898aba41b