[INFO] updating cached repository k2bd/star_battle_mc_solver
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/k2bd/star_battle_mc_solver
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/k2bd/star_battle_mc_solver" "work/ex/clippy-test-run/sources/stable/gh/k2bd/star_battle_mc_solver"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/k2bd/star_battle_mc_solver'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/k2bd/star_battle_mc_solver" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/k2bd/star_battle_mc_solver"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/k2bd/star_battle_mc_solver'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3c62c3ca2292e3646fcc9b021e097eb71be6a772
[INFO] sha for GitHub repo k2bd/star_battle_mc_solver: 3c62c3ca2292e3646fcc9b021e097eb71be6a772
[INFO] validating manifest of k2bd/star_battle_mc_solver 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 k2bd/star_battle_mc_solver 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 k2bd/star_battle_mc_solver
[INFO] finished frobbing k2bd/star_battle_mc_solver
[INFO] frobbed toml for k2bd/star_battle_mc_solver written to work/ex/clippy-test-run/sources/stable/gh/k2bd/star_battle_mc_solver/Cargo.toml
[INFO] started frobbing k2bd/star_battle_mc_solver
[INFO] finished frobbing k2bd/star_battle_mc_solver
[INFO] frobbed toml for k2bd/star_battle_mc_solver written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/k2bd/star_battle_mc_solver/Cargo.toml
[INFO] crate k2bd/star_battle_mc_solver 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 k2bd/star_battle_mc_solver against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-3/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/gh/k2bd/star_battle_mc_solver:/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] 54b9094a23dbe0129a9d92286c77bbfb0daa68b74b77b15638891b8847975add
[INFO] running `"docker" "start" "-a" "54b9094a23dbe0129a9d92286c77bbfb0daa68b74b77b15638891b8847975add"`
[INFO] [stderr]     Checking star_battle v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `rand::Rng`
[INFO] [stderr]  --> src/main.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use rand::Rng;
[INFO] [stderr]   |     ^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `rand::Rng`
[INFO] [stderr]  --> src/main.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use rand::Rng;
[INFO] [stderr]   |     ^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `regions`
[INFO] [stderr]   --> src/main.rs:92:39
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn score(star_board: &Vec<Vec<bool>>, regions: &Vec<Vec<char>>, n_stars: usize) -> usize {
[INFO] [stderr]    |                                       ^^^^^^^ help: consider using `_regions` instead
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `row`
[INFO] [stderr]    --> src/main.rs:131:9
[INFO] [stderr]     |
[INFO] [stderr] 131 |     for row in board {
[INFO] [stderr]     |         ^^^ help: consider using `_row` instead
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let mut filename;
[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: unused variable: `regions`
[INFO] [stderr]   --> src/main.rs:92:39
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn score(star_board: &Vec<Vec<bool>>, regions: &Vec<Vec<char>>, n_stars: usize) -> usize {
[INFO] [stderr]    |                                       ^^^^^^^ help: consider using `_regions` instead
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `row`
[INFO] [stderr]    --> src/main.rs:131:9
[INFO] [stderr]     |
[INFO] [stderr] 131 |     for row in board {
[INFO] [stderr]     |         ^^^ help: consider using `_row` instead
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]   --> src/main.rs:14:5
[INFO] [stderr]    |
[INFO] [stderr] 14 | /     let mut filename;
[INFO] [stderr] 15 | |     if args.len() == 1 {
[INFO] [stderr] 16 | |         filename = "example.txt".to_string();
[INFO] [stderr] 17 | |     } else {
[INFO] [stderr] 18 | |         filename = args[1].clone() + ".txt";
[INFO] [stderr] 19 | |     }
[INFO] [stderr]    | |_____^ help: it is more idiomatic to write: `let <mut> filename = if args.len() == 1 { "example.txt".to_string() } else { args[1].clone() + ".txt" };`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::useless_let_if_seq)] on by default
[INFO] [stderr]    = note: you might not need `mut` at all
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: use of `expect` followed by a function call
[INFO] [stderr]   --> src/main.rs:21:39
[INFO] [stderr]    |
[INFO] [stderr] 21 |     let mut f = File::open(&filename).expect(format!("Could not open file {}",filename).as_ref());
[INFO] [stderr]    |                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|_| panic!("Could not open file {}", filename))`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::expect_fun_call)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#expect_fun_call
[INFO] [stderr] 
[INFO] [stderr] warning: use of `expect` followed by a function call
[INFO] [stderr]   --> src/main.rs:25:44
[INFO] [stderr]    |
[INFO] [stderr] 25 |     f.read_to_string(&mut contents_string).expect(format!("Couldn't read contents of file {}",filename).as_ref());
[INFO] [stderr]    |                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|_| panic!("Couldn't read contents of file {}", filename))`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#expect_fun_call
[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:88:27
[INFO] [stderr]    |
[INFO] [stderr] 88 | fn star_count(star_board: &Vec<Vec<bool>>) -> usize {
[INFO] [stderr]    |                           ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<bool>]`
[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:92:22
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn score(star_board: &Vec<Vec<bool>>, regions: &Vec<Vec<char>>, n_stars: usize) -> usize {
[INFO] [stderr]    |                      ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<bool>]`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let mut filename;
[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: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]   --> src/main.rs:92:48
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn score(star_board: &Vec<Vec<bool>>, regions: &Vec<Vec<char>>, n_stars: usize) -> usize {
[INFO] [stderr]    |                                                ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<char>]`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: the loop variable `i` is only used to index `star_board`.
[INFO] [stderr]   --> src/main.rs:95:14
[INFO] [stderr]    |
[INFO] [stderr] 95 |     for i in 0..star_board.len() {
[INFO] [stderr]    |              ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_range_loop)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop
[INFO] [stderr] help: consider using an iterator
[INFO] [stderr]    |
[INFO] [stderr] 95 |     for <item> in &star_board {
[INFO] [stderr]    |         ^^^^^^    ^^^^^^^^^^^
[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:108:23
[INFO] [stderr]     |
[INFO] [stderr] 108 | fn mutate(star_board: &Vec<Vec<bool>>) -> Vec<Vec<bool>>{
[INFO] [stderr]     |                       ^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] help: change this to
[INFO] [stderr]     |
[INFO] [stderr] 108 | fn mutate(star_board: &[Vec<bool>]) -> Vec<Vec<bool>>{
[INFO] [stderr]     |                       ^^^^^^^^^^^^
[INFO] [stderr] help: change `star_board.clone()` to
[INFO] [stderr]     |
[INFO] [stderr] 109 |     let mut board = star_board.to_owned();
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^
[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:128:23
[INFO] [stderr]     |
[INFO] [stderr] 128 | fn print_board(board: &Vec<Vec<bool>>) {
[INFO] [stderr]     |                       ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<bool>]`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: `if _ { .. } else { .. }` is an expression
[INFO] [stderr]   --> src/main.rs:14:5
[INFO] [stderr]    |
[INFO] [stderr] 14 | /     let mut filename;
[INFO] [stderr] 15 | |     if args.len() == 1 {
[INFO] [stderr] 16 | |         filename = "example.txt".to_string();
[INFO] [stderr] 17 | |     } else {
[INFO] [stderr] 18 | |         filename = args[1].clone() + ".txt";
[INFO] [stderr] 19 | |     }
[INFO] [stderr]    | |_____^ help: it is more idiomatic to write: `let <mut> filename = if args.len() == 1 { "example.txt".to_string() } else { args[1].clone() + ".txt" };`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::useless_let_if_seq)] on by default
[INFO] [stderr]    = note: you might not need `mut` at all
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_let_if_seq
[INFO] [stderr] 
[INFO] [stderr] warning: use of `expect` followed by a function call
[INFO] [stderr]   --> src/main.rs:21:39
[INFO] [stderr]    |
[INFO] [stderr] 21 |     let mut f = File::open(&filename).expect(format!("Could not open file {}",filename).as_ref());
[INFO] [stderr]    |                                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|_| panic!("Could not open file {}", filename))`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::expect_fun_call)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#expect_fun_call
[INFO] [stderr] 
[INFO] [stderr] warning: use of `expect` followed by a function call
[INFO] [stderr]   --> src/main.rs:25:44
[INFO] [stderr]    |
[INFO] [stderr] 25 |     f.read_to_string(&mut contents_string).expect(format!("Couldn't read contents of file {}",filename).as_ref());
[INFO] [stderr]    |                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `unwrap_or_else(|_| panic!("Couldn't read contents of file {}", filename))`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#expect_fun_call
[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:88:27
[INFO] [stderr]    |
[INFO] [stderr] 88 | fn star_count(star_board: &Vec<Vec<bool>>) -> usize {
[INFO] [stderr]    |                           ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<bool>]`
[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:92:22
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn score(star_board: &Vec<Vec<bool>>, regions: &Vec<Vec<char>>, n_stars: usize) -> usize {
[INFO] [stderr]    |                      ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<bool>]`
[INFO] [stderr]    |
[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:92:48
[INFO] [stderr]    |
[INFO] [stderr] 92 | fn score(star_board: &Vec<Vec<bool>>, regions: &Vec<Vec<char>>, n_stars: usize) -> usize {
[INFO] [stderr]    |                                                ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<char>]`
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: the loop variable `i` is only used to index `star_board`.
[INFO] [stderr]   --> src/main.rs:95:14
[INFO] [stderr]    |
[INFO] [stderr] 95 |     for i in 0..star_board.len() {
[INFO] [stderr]    |              ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_range_loop)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_range_loop
[INFO] [stderr] help: consider using an iterator
[INFO] [stderr]    |
[INFO] [stderr] 95 |     for <item> in &star_board {
[INFO] [stderr]    |         ^^^^^^    ^^^^^^^^^^^
[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:108:23
[INFO] [stderr]     |
[INFO] [stderr] 108 | fn mutate(star_board: &Vec<Vec<bool>>) -> Vec<Vec<bool>>{
[INFO] [stderr]     |                       ^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] help: change this to
[INFO] [stderr]     |
[INFO] [stderr] 108 | fn mutate(star_board: &[Vec<bool>]) -> Vec<Vec<bool>>{
[INFO] [stderr]     |                       ^^^^^^^^^^^^
[INFO] [stderr] help: change `star_board.clone()` to
[INFO] [stderr]     |
[INFO] [stderr] 109 |     let mut board = star_board.to_owned();
[INFO] [stderr]     |                     ^^^^^^^^^^^^^^^^^^^^^
[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:128:23
[INFO] [stderr]     |
[INFO] [stderr] 128 | fn print_board(board: &Vec<Vec<bool>>) {
[INFO] [stderr]     |                       ^^^^^^^^^^^^^^^ help: change this to: `&[Vec<bool>]`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.08s
[INFO] running `"docker" "inspect" "54b9094a23dbe0129a9d92286c77bbfb0daa68b74b77b15638891b8847975add"`
[INFO] running `"docker" "rm" "-f" "54b9094a23dbe0129a9d92286c77bbfb0daa68b74b77b15638891b8847975add"`
[INFO] [stdout] 54b9094a23dbe0129a9d92286c77bbfb0daa68b74b77b15638891b8847975add