[INFO] updating cached repository Anfauglith/sudoku
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Anfauglith/sudoku
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Anfauglith/sudoku" "work/ex/beta-1.38-1/sources/1.37.0/gh/Anfauglith/sudoku"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/Anfauglith/sudoku'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Anfauglith/sudoku" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Anfauglith/sudoku"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Anfauglith/sudoku'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 198a8b8f2a95bbbc42d9691a5c8a017d1b397c46
[INFO] sha for GitHub repo Anfauglith/sudoku: 198a8b8f2a95bbbc42d9691a5c8a017d1b397c46
[INFO] validating manifest of Anfauglith/sudoku 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 Anfauglith/sudoku 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 Anfauglith/sudoku
[INFO] finished frobbing Anfauglith/sudoku
[INFO] frobbed toml for Anfauglith/sudoku written to work/ex/beta-1.38-1/sources/1.37.0/gh/Anfauglith/sudoku/Cargo.toml
[INFO] started frobbing Anfauglith/sudoku
[INFO] finished frobbing Anfauglith/sudoku
[INFO] frobbed toml for Anfauglith/sudoku written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/Anfauglith/sudoku/Cargo.toml
[INFO] crate Anfauglith/sudoku 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 Anfauglith/sudoku 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/Anfauglith/sudoku:/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] 2709267bbecbdb1d5e883421d0bb106c83fcafcaaf17c02f3bb3cbb6f29410a5
[INFO] running `"docker" "start" "-a" "2709267bbecbdb1d5e883421d0bb106c83fcafcaaf17c02f3bb3cbb6f29410a5"`
[INFO] [stderr]    Compiling sudoku v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: constant item is never used: `CANDIDATE_MASK`
[INFO] [stderr]  --> src/field.rs:2:1
[INFO] [stderr]   |
[INFO] [stderr] 2 | const CANDIDATE_MASK: u16 = 0b0000_0011_1111_1110; // 0x03FE
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Field`
[INFO] [stderr]  --> src/field.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | pub struct Field {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: struct is never constructed: `Cell`
[INFO] [stderr]  --> src/field.rs:8:1
[INFO] [stderr]   |
[INFO] [stderr] 8 | pub struct Cell {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `empty_cell`
[INFO] [stderr]   --> src/field.rs:16:5
[INFO] [stderr]    |
[INFO] [stderr] 16 |     pub fn empty_cell() -> Cell {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `fixed_cell`
[INFO] [stderr]   --> src/field.rs:24:5
[INFO] [stderr]    |
[INFO] [stderr] 24 |     pub fn fixed_cell(digit: u8) -> Cell {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `is_solved`
[INFO] [stderr]   --> src/field.rs:32:5
[INFO] [stderr]    |
[INFO] [stderr] 32 |     pub fn is_solved(&self) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `is_fixed`
[INFO] [stderr]   --> src/field.rs:39:5
[INFO] [stderr]    |
[INFO] [stderr] 39 |     pub fn is_fixed(&self) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `get_digit`
[INFO] [stderr]   --> src/field.rs:43:5
[INFO] [stderr]    |
[INFO] [stderr] 43 |     pub fn get_digit(&self) -> Option<u8> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `fix`
[INFO] [stderr]   --> src/field.rs:47:5
[INFO] [stderr]    |
[INFO] [stderr] 47 |     fn fix(&mut self) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `set_to`
[INFO] [stderr]   --> src/field.rs:55:5
[INFO] [stderr]    |
[INFO] [stderr] 55 |     fn set_to(&mut self, digit: u8) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `fix_to`
[INFO] [stderr]   --> src/field.rs:66:5
[INFO] [stderr]    |
[INFO] [stderr] 66 |     pub fn fix_to(&mut self, digit: u8) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `has_candidate`
[INFO] [stderr]   --> src/field.rs:73:5
[INFO] [stderr]    |
[INFO] [stderr] 73 |     pub fn has_candidate(&self, candidate: u8) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `get_candidates`
[INFO] [stderr]   --> src/field.rs:77:5
[INFO] [stderr]    |
[INFO] [stderr] 77 |     pub fn get_candidates(&self) -> u16 {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `get_candidate_vector`
[INFO] [stderr]   --> src/field.rs:81:5
[INFO] [stderr]    |
[INFO] [stderr] 81 |     pub fn get_candidate_vector(&self) -> Vec<u8> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `remove_candidate`
[INFO] [stderr]   --> src/field.rs:91:5
[INFO] [stderr]    |
[INFO] [stderr] 91 |     pub fn remove_candidate(&mut self, candidate: u8) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `remove_candidates`
[INFO] [stderr]   --> src/field.rs:96:5
[INFO] [stderr]    |
[INFO] [stderr] 96 |     pub fn remove_candidates(&mut self, candidates: Vec<u8>) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `has_single_candidate`
[INFO] [stderr]    --> src/field.rs:102:5
[INFO] [stderr]     |
[INFO] [stderr] 102 |     pub fn has_single_candidate(&self) -> bool {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `get_naked_single`
[INFO] [stderr]    --> src/field.rs:106:5
[INFO] [stderr]     |
[INFO] [stderr] 106 |     pub fn get_naked_single(&self) -> Option<u8> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `try_solve`
[INFO] [stderr]    --> src/field.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     pub fn try_solve(&mut self) -> bool {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.70s
[INFO] running `"docker" "inspect" "2709267bbecbdb1d5e883421d0bb106c83fcafcaaf17c02f3bb3cbb6f29410a5"`
[INFO] running `"docker" "rm" "-f" "2709267bbecbdb1d5e883421d0bb106c83fcafcaaf17c02f3bb3cbb6f29410a5"`
[INFO] [stdout] 2709267bbecbdb1d5e883421d0bb106c83fcafcaaf17c02f3bb3cbb6f29410a5
[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/Anfauglith/sudoku:/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] c25f288e356f094f7b5f8934c9a6f7c95077b9959520abb879120982f0348694
[INFO] running `"docker" "start" "-a" "c25f288e356f094f7b5f8934c9a6f7c95077b9959520abb879120982f0348694"`
[INFO] [stderr]    Compiling sudoku v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: struct is never constructed: `Field`
[INFO] [stderr]  --> src/field.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | pub struct Field {
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `is_solved`
[INFO] [stderr]   --> src/field.rs:32:5
[INFO] [stderr]    |
[INFO] [stderr] 32 |     pub fn is_solved(&self) -> bool {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.11s
[INFO] running `"docker" "inspect" "c25f288e356f094f7b5f8934c9a6f7c95077b9959520abb879120982f0348694"`
[INFO] running `"docker" "rm" "-f" "c25f288e356f094f7b5f8934c9a6f7c95077b9959520abb879120982f0348694"`
[INFO] [stdout] c25f288e356f094f7b5f8934c9a6f7c95077b9959520abb879120982f0348694
[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/Anfauglith/sudoku:/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] 15ae5fb26aea93965ae7614dfb51dc063e66531d26a785686420c547aa3a49f4
[INFO] running `"docker" "start" "-a" "15ae5fb26aea93965ae7614dfb51dc063e66531d26a785686420c547aa3a49f4"`
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stdout] running 2 tests
[INFO] [stderr]      Running /opt/crater/target/debug/deps/sudoku-7e53c9af5f494d61
[INFO] [stdout] test field::tests::cell_fixing ... ok
[INFO] [stdout] test field::tests::removing_candidates_and_solving ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "15ae5fb26aea93965ae7614dfb51dc063e66531d26a785686420c547aa3a49f4"`
[INFO] running `"docker" "rm" "-f" "15ae5fb26aea93965ae7614dfb51dc063e66531d26a785686420c547aa3a49f4"`
[INFO] [stdout] 15ae5fb26aea93965ae7614dfb51dc063e66531d26a785686420c547aa3a49f4