[INFO] updating cached repository swizzard/boggler
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/swizzard/boggler
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/swizzard/boggler" "work/ex/beta-1.38-1/sources/1.37.0/gh/swizzard/boggler"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/swizzard/boggler'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/swizzard/boggler" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/swizzard/boggler"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/swizzard/boggler'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] cc01442ec61024df5448d8460f06d2fcdd7e2531
[INFO] sha for GitHub repo swizzard/boggler: cc01442ec61024df5448d8460f06d2fcdd7e2531
[INFO] validating manifest of swizzard/boggler on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of swizzard/boggler on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing swizzard/boggler
[INFO] finished frobbing swizzard/boggler
[INFO] frobbed toml for swizzard/boggler written to work/ex/beta-1.38-1/sources/1.37.0/gh/swizzard/boggler/Cargo.toml
[INFO] started frobbing swizzard/boggler
[INFO] finished frobbing swizzard/boggler
[INFO] frobbed toml for swizzard/boggler written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/swizzard/boggler/Cargo.toml
[INFO] crate swizzard/boggler already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing swizzard/boggler against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-4/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/swizzard/boggler:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] ea68fe9b12b793d7e7e7702d3f1bee4354306110f1fdea5a47775e07f57b39c2
[INFO] running `"docker" "start" "-a" "ea68fe9b12b793d7e7e7702d3f1bee4354306110f1fdea5a47775e07f57b39c2"`
[INFO] [stderr]    Compiling rand v0.5.1
[INFO] [stderr]    Compiling boggler v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `seen`
[INFO] [stderr]    --> src/solver.rs:156:17
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |                 ^^^^ help: consider prefixing with an underscore: `_seen`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `adjcts`
[INFO] [stderr]    --> src/solver.rs:158:17
[INFO] [stderr]     |
[INFO] [stderr] 158 |             let adjcts = board.adjacents(x, y);
[INFO] [stderr]     |                 ^^^^^^ help: consider prefixing with an underscore: `_adjcts`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:154:13
[INFO] [stderr]     |
[INFO] [stderr] 154 |         let mut x = 0;
[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/solver.rs:155:13
[INFO] [stderr]     |
[INFO] [stderr] 155 |         let mut y = 0;
[INFO] [stderr]     |             ----^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:156:13
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `find_letter`
[INFO] [stderr]    --> src/solver.rs:149:5
[INFO] [stderr]     |
[INFO] [stderr] 149 |     fn find_letter(&self, chr: &AsciiChar) -> Option<&BTNode> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 7.30s
[INFO] running `"docker" "inspect" "ea68fe9b12b793d7e7e7702d3f1bee4354306110f1fdea5a47775e07f57b39c2"`
[INFO] running `"docker" "rm" "-f" "ea68fe9b12b793d7e7e7702d3f1bee4354306110f1fdea5a47775e07f57b39c2"`
[INFO] [stdout] ea68fe9b12b793d7e7e7702d3f1bee4354306110f1fdea5a47775e07f57b39c2
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-4/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/swizzard/boggler:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "test" "--frozen" "--no-run"`
[INFO] [stdout] b5395a06ecc0650a2efd4f6fcb406e1dd5244ae0299029ac3bbe7cdaf9850e0e
[INFO] running `"docker" "start" "-a" "b5395a06ecc0650a2efd4f6fcb406e1dd5244ae0299029ac3bbe7cdaf9850e0e"`
[INFO] [stderr]    Compiling boggler v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `seen`
[INFO] [stderr]    --> src/solver.rs:156:17
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |                 ^^^^ help: consider prefixing with an underscore: `_seen`
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `adjcts`
[INFO] [stderr]    --> src/solver.rs:158:17
[INFO] [stderr]     |
[INFO] [stderr] 158 |             let adjcts = board.adjacents(x, y);
[INFO] [stderr]     |                 ^^^^^^ help: consider prefixing with an underscore: `_adjcts`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:154:13
[INFO] [stderr]     |
[INFO] [stderr] 154 |         let mut x = 0;
[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/solver.rs:155:13
[INFO] [stderr]     |
[INFO] [stderr] 155 |         let mut y = 0;
[INFO] [stderr]     |             ----^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/solver.rs:156:13
[INFO] [stderr]     |
[INFO] [stderr] 156 |         let mut seen: HashSet<BoardPosition> = HashSet::with_capacity(16);
[INFO] [stderr]     |             ----^^^^
[INFO] [stderr]     |             |
[INFO] [stderr]     |             help: remove this `mut`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.64s
[INFO] running `"docker" "inspect" "b5395a06ecc0650a2efd4f6fcb406e1dd5244ae0299029ac3bbe7cdaf9850e0e"`
[INFO] running `"docker" "rm" "-f" "b5395a06ecc0650a2efd4f6fcb406e1dd5244ae0299029ac3bbe7cdaf9850e0e"`
[INFO] [stdout] b5395a06ecc0650a2efd4f6fcb406e1dd5244ae0299029ac3bbe7cdaf9850e0e
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-4/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/swizzard/boggler:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+beta-2019-08-13" "test" "--frozen"`
[INFO] [stdout] 2d3a8078dfeded4d33c468896e9a87fc29a9b1055a997e2e2a26fdd25e44c51e
[INFO] running `"docker" "start" "-a" "2d3a8078dfeded4d33c468896e9a87fc29a9b1055a997e2e2a26fdd25e44c51e"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/boggler-0d15285ec8cd4538
[INFO] [stdout] 
[INFO] [stdout] running 16 tests
[INFO] [stdout] test board::test::test_adjacents_bottom ... ok
[INFO] [stdout] test board::test::test_adjacents_middle ... ok
[INFO] [stdout] test board::test::test_adjacents_left_side ... ok
[INFO] [stdout] test board::test::test_adjacents_top ... ok
[INFO] [stdout] test board::test::test_adjacents_right_side ... ok
[INFO] [stdout] test solver::test::count_word_q ... ok
[INFO] [stdout] test solver::test::count_word_u_no_q ... ok
[INFO] [stdout] test solver::test::count_word_no_q ... ok
[INFO] [stdout] test solver::test::two_new_words ... ok
[INFO] [stdout] test solver::test::prepare_word_lowercase ... ok
[INFO] [stdout] test solver::test::find_letter ... ok
[INFO] [stdout] test solver::test::new_one_word ... ok
[INFO] [stdout] test solver::test::new_empty ... ok
[INFO] [stdout] test solver::test::find ... ok
[INFO] [stdout] test board::test::test_adjacents_upper_left_corner ... ok
[INFO] [stdout] test board::test::test_adjacents_upper_right_corner ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 16 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/crater/target/debug/deps/boggler-79560329ea3be7d4
[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
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests boggler
[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
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "2d3a8078dfeded4d33c468896e9a87fc29a9b1055a997e2e2a26fdd25e44c51e"`
[INFO] running `"docker" "rm" "-f" "2d3a8078dfeded4d33c468896e9a87fc29a9b1055a997e2e2a26fdd25e44c51e"`
[INFO] [stdout] 2d3a8078dfeded4d33c468896e9a87fc29a9b1055a997e2e2a26fdd25e44c51e