[INFO] updating cached repository gnuvince/sudoku-rs
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/gnuvince/sudoku-rs
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/gnuvince/sudoku-rs" "work/ex/clippy-test-run/sources/stable/gh/gnuvince/sudoku-rs"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/gnuvince/sudoku-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/gnuvince/sudoku-rs" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/gnuvince/sudoku-rs"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/gnuvince/sudoku-rs'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 2e14751a3731aa8121d119f4060dd39843c8e0f5
[INFO] sha for GitHub repo gnuvince/sudoku-rs: 2e14751a3731aa8121d119f4060dd39843c8e0f5
[INFO] validating manifest of gnuvince/sudoku-rs on toolchain stable
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of gnuvince/sudoku-rs on toolchain stable+rustflags=-Dclippy::into_iter_on_array
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing gnuvince/sudoku-rs
[INFO] finished frobbing gnuvince/sudoku-rs
[INFO] frobbed toml for gnuvince/sudoku-rs written to work/ex/clippy-test-run/sources/stable/gh/gnuvince/sudoku-rs/Cargo.toml
[INFO] started frobbing gnuvince/sudoku-rs
[INFO] finished frobbing gnuvince/sudoku-rs
[INFO] frobbed toml for gnuvince/sudoku-rs written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/gnuvince/sudoku-rs/Cargo.toml
[INFO] crate gnuvince/sudoku-rs has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] linting gnuvince/sudoku-rs against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-0/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/gh/gnuvince/sudoku-rs:/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=forbid" "-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" "+stable" "clippy" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 983312b16875184d98f74ebdc65fc92dda42acba739ded0e1c2a18dd98c6ec1a
[INFO] running `"docker" "start" "-a" "983312b16875184d98f74ebdc65fc92dda42acba739ded0e1c2a18dd98c6ec1a"`
[INFO] [stderr]     Checking sudoku v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/main.rs:60:5
[INFO] [stderr]    |
[INFO] [stderr] 60 |     return all_neighbors.into_iter().collect();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `all_neighbors.into_iter().collect()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/main.rs:95:9
[INFO] [stderr]    |
[INFO] [stderr] 95 |         return SudokuBoard { cells, neighbors };
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `SudokuBoard { cells, neighbors }`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |         return set;
[INFO] [stderr]     |         ^^^^^^^^^^^ help: remove `return` as shown: `set`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:142:9
[INFO] [stderr]     |
[INFO] [stderr] 142 |         return output;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^ help: remove `return` as shown: `output`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:199:9
[INFO] [stderr]     |
[INFO] [stderr] 199 |         return None;
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: remove `return` as shown: `None`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:223:5
[INFO] [stderr]     |
[INFO] [stderr] 223 |     return i;
[INFO] [stderr]     |     ^^^^^^^^^ help: remove `return` as shown: `i`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/main.rs:60:5
[INFO] [stderr]    |
[INFO] [stderr] 60 |     return all_neighbors.into_iter().collect();
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `all_neighbors.into_iter().collect()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/main.rs:95:9
[INFO] [stderr]    |
[INFO] [stderr] 95 |         return SudokuBoard { cells, neighbors };
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `SudokuBoard { cells, neighbors }`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |         return set;
[INFO] [stderr]     |         ^^^^^^^^^^^ help: remove `return` as shown: `set`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:142:9
[INFO] [stderr]     |
[INFO] [stderr] 142 |         return output;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^ help: remove `return` as shown: `output`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:199:9
[INFO] [stderr]     |
[INFO] [stderr] 199 |         return None;
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: remove `return` as shown: `None`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/main.rs:223:5
[INFO] [stderr]     |
[INFO] [stderr] 223 |     return i;
[INFO] [stderr]     |     ^^^^^^^^^ help: remove `return` as shown: `i`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]   --> src/main.rs:76:42
[INFO] [stderr]    |
[INFO] [stderr] 76 |     fn from_str(digits: &str, neighbors: &'a Vec<Vec<usize>>) -> Self {
[INFO] [stderr]    |                                          ^^^^^^^^^^^^^^^^^^^ help: change this to: `&[Vec<usize>]`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]   --> src/main.rs:76:42
[INFO] [stderr]    |
[INFO] [stderr] 76 |     fn from_str(digits: &str, neighbors: &'a Vec<Vec<usize>>) -> Self {
[INFO] [stderr]    |                                          ^^^^^^^^^^^^^^^^^^^ help: change this to: `&[Vec<usize>]`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/main.rs:192:17
[INFO] [stderr]     |
[INFO] [stderr] 192 | /                 match newboard.solve() {
[INFO] [stderr] 193 | |                     Some(solved_board) => { return Some(solved_board); }
[INFO] [stderr] 194 | |                     None => { }
[INFO] [stderr] 195 | |                 }
[INFO] [stderr]     | |_________________^ help: try this: `if let Some(solved_board) = newboard.solve() { return Some(solved_board); }`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::single_match)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/main.rs:192:17
[INFO] [stderr]     |
[INFO] [stderr] 192 | /                 match newboard.solve() {
[INFO] [stderr] 193 | |                     Some(solved_board) => { return Some(solved_board); }
[INFO] [stderr] 194 | |                     None => { }
[INFO] [stderr] 195 | |                 }
[INFO] [stderr]     | |_________________^ help: try this: `if let Some(solved_board) = newboard.solve() { return Some(solved_board); }`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::single_match)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.92s
[INFO] running `"docker" "inspect" "983312b16875184d98f74ebdc65fc92dda42acba739ded0e1c2a18dd98c6ec1a"`
[INFO] running `"docker" "rm" "-f" "983312b16875184d98f74ebdc65fc92dda42acba739ded0e1c2a18dd98c6ec1a"`
[INFO] [stdout] 983312b16875184d98f74ebdc65fc92dda42acba739ded0e1c2a18dd98c6ec1a