[INFO] cloning repository https://github.com/skade/rust-three-days-course
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/skade/rust-three-days-course" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fskade%2Frust-three-days-course", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fskade%2Frust-three-days-course'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d9aba866d24f7755da23a2e16d4865cf29d2d8f5
[INFO] testing skade/rust-three-days-course against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fskade%2Frust-three-days-course" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/skade/rust-three-days-course 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/skade/rust-three-days-course
[INFO] finished tweaking git repo https://github.com/skade/rust-three-days-course
[INFO] tweaked toml for git repo https://github.com/skade/rust-three-days-course written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/skade/rust-three-days-course 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 8b1deb80f61ea6aa3c868564f23627d473ae81c7c9412a8dc158ce9ede557a20
[INFO] running `Command { std: "docker" "start" "-a" "8b1deb80f61ea6aa3c868564f23627d473ae81c7c9412a8dc158ce9ede557a20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8b1deb80f61ea6aa3c868564f23627d473ae81c7c9412a8dc158ce9ede557a20", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8b1deb80f61ea6aa3c868564f23627d473ae81c7c9412a8dc158ce9ede557a20", kill_on_drop: false }`
[INFO] [stdout] 8b1deb80f61ea6aa3c868564f23627d473ae81c7c9412a8dc158ce9ede557a20
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 6c4db436ac3e88ce22697eaf31eb47510ccac52a845f1f86c14e3925f046dd6a
[INFO] running `Command { std: "docker" "start" "-a" "6c4db436ac3e88ce22697eaf31eb47510ccac52a845f1f86c14e3925f046dd6a", kill_on_drop: false }`
[INFO] [stderr]    Compiling unicode-xid v0.0.4
[INFO] [stderr]    Compiling quote v0.3.15
[INFO] [stderr]    Compiling num-traits v0.1.37
[INFO] [stderr]    Compiling itoa v0.3.1
[INFO] [stderr]    Compiling serde v0.9.12
[INFO] [stderr]    Compiling dtoa v0.4.1
[INFO] [stderr]    Compiling shells v0.2.0
[INFO] [stderr]    Compiling glob v0.2.11
[INFO] [stderr]    Compiling synom v0.11.3
[INFO] [stderr]    Compiling syn v0.11.9
[INFO] [stderr]    Compiling serde_codegen_internals v0.14.2
[INFO] [stderr]    Compiling serde_derive v0.9.12
[INFO] [stderr]    Compiling serde_json v0.9.9
[INFO] [stderr]    Compiling pandoc_types v0.1.0
[INFO] [stderr]    Compiling tasks v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/bin/extract-code.rs:67:17
[INFO] [stdout]    |
[INFO] [stdout] 67 |                 std::mem::replace(block, new_block);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 21.28s
[INFO] running `Command { std: "docker" "inspect" "6c4db436ac3e88ce22697eaf31eb47510ccac52a845f1f86c14e3925f046dd6a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6c4db436ac3e88ce22697eaf31eb47510ccac52a845f1f86c14e3925f046dd6a", kill_on_drop: false }`
[INFO] [stdout] 6c4db436ac3e88ce22697eaf31eb47510ccac52a845f1f86c14e3925f046dd6a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 31b067a2c70ebb9ca903524b1683de9320a1cc4b39d587dd165141f5d4605218
[INFO] running `Command { std: "docker" "start" "-a" "31b067a2c70ebb9ca903524b1683de9320a1cc4b39d587dd165141f5d4605218", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling tasks v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/bin/extract-code.rs:67:17
[INFO] [stdout]    |
[INFO] [stdout] 67 |                 std::mem::replace(block, new_block);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.82s
[INFO] running `Command { std: "docker" "inspect" "31b067a2c70ebb9ca903524b1683de9320a1cc4b39d587dd165141f5d4605218", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31b067a2c70ebb9ca903524b1683de9320a1cc4b39d587dd165141f5d4605218", kill_on_drop: false }`
[INFO] [stdout] 31b067a2c70ebb9ca903524b1683de9320a1cc4b39d587dd165141f5d4605218
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] d206fa4497cc8ece70fcd57972ed14bf0990a0d2016a045268304f7dcf28c548
[INFO] running `Command { std: "docker" "start" "-a" "d206fa4497cc8ece70fcd57972ed14bf0990a0d2016a045268304f7dcf28c548", kill_on_drop: false }`
[INFO] [stderr] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stderr]   --> src/bin/extract-code.rs:67:17
[INFO] [stderr]    |
[INFO] [stderr] 67 |                 std::mem::replace(block, new_block);
[INFO] [stderr]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stderr] 
[INFO] [stderr] warning: `tasks` (bin "extract-code" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/tasks-5b17cd3bceb2d884)
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/add_chapter-ecbe4ad1c43a51cb)
[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 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/add_code_example-a11b9bcd6b3b09b9)
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/build_indices-f89f42a9e98dd1de)
[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/extract_code-0bb2cd810d6a6f60)
[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 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/rename_chapter-9ce9f32f8e1f5c42)
[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/rename_chapters-5cdd823e6c5691e4)
[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]    Doc-tests tasks
[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" "d206fa4497cc8ece70fcd57972ed14bf0990a0d2016a045268304f7dcf28c548", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d206fa4497cc8ece70fcd57972ed14bf0990a0d2016a045268304f7dcf28c548", kill_on_drop: false }`
[INFO] [stdout] d206fa4497cc8ece70fcd57972ed14bf0990a0d2016a045268304f7dcf28c548