[INFO] updating cached repository clu8/rust-exercises
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/clu8/rust-exercises
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/clu8/rust-exercises" "work/ex/clippy-test-run/sources/stable/gh/clu8/rust-exercises"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/clu8/rust-exercises'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/clu8/rust-exercises" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/clu8/rust-exercises"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/clu8/rust-exercises'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 809d444104da2b8c4d6681a133acb5a5d13a02b3
[INFO] sha for GitHub repo clu8/rust-exercises: 809d444104da2b8c4d6681a133acb5a5d13a02b3
[INFO] validating manifest of clu8/rust-exercises 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 clu8/rust-exercises 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 clu8/rust-exercises
[INFO] finished frobbing clu8/rust-exercises
[INFO] frobbed toml for clu8/rust-exercises written to work/ex/clippy-test-run/sources/stable/gh/clu8/rust-exercises/Cargo.toml
[INFO] started frobbing clu8/rust-exercises
[INFO] finished frobbing clu8/rust-exercises
[INFO] frobbed toml for clu8/rust-exercises written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/clu8/rust-exercises/Cargo.toml
[INFO] crate clu8/rust-exercises 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 clu8/rust-exercises 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/clu8/rust-exercises:/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] 4bde20840d8d79d8b0d74b4a11478880762308f409c59a33a42168b4f4a62d7e
[INFO] running `"docker" "start" "-a" "4bde20840d8d79d8b0d74b4a11478880762308f409c59a33a42168b4f4a62d7e"`
[INFO] [stderr]     Checking exercises v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/program.rs:47:9
[INFO] [stderr]    |
[INFO] [stderr] 47 |         return Err("empty program");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("empty program")`
[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/program.rs:51:13
[INFO] [stderr]    |
[INFO] [stderr] 51 |             return Err("invalid program");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("invalid program")`
[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/program.rs:54:13
[INFO] [stderr]    |
[INFO] [stderr] 54 |             return Ok(Program { paren });
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Ok(Program { paren })`
[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/program.rs:57:9
[INFO] [stderr]    |
[INFO] [stderr] 57 |         return Err("invalid program");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("invalid program")`
[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/program.rs:65:9
[INFO] [stderr]    |
[INFO] [stderr] 65 |         return Err("invalid program");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("invalid program")`
[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/program.rs:78:9
[INFO] [stderr]    |
[INFO] [stderr] 78 |         return Ok((paren, i + 1));
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Ok((paren, i + 1))`
[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/program.rs:47:9
[INFO] [stderr]    |
[INFO] [stderr] 47 |         return Err("empty program");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("empty program")`
[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/program.rs:51:13
[INFO] [stderr]    |
[INFO] [stderr] 51 |             return Err("invalid program");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("invalid program")`
[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/program.rs:54:13
[INFO] [stderr]    |
[INFO] [stderr] 54 |             return Ok(Program { paren });
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Ok(Program { paren })`
[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/program.rs:57:9
[INFO] [stderr]    |
[INFO] [stderr] 57 |         return Err("invalid program");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("invalid program")`
[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/program.rs:65:9
[INFO] [stderr]    |
[INFO] [stderr] 65 |         return Err("invalid program");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Err("invalid program")`
[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/program.rs:78:9
[INFO] [stderr]    |
[INFO] [stderr] 78 |         return Ok((paren, i + 1));
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `Ok((paren, i + 1))`
[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 `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]   --> src/program.rs:39:24
[INFO] [stderr]    |
[INFO] [stderr] 39 | pub fn str_to_chars(s: &String) -> Vec<char> {
[INFO] [stderr]    |                        ^^^^^^^ help: change this to: `&str`
[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: length comparison to zero
[INFO] [stderr]   --> src/program.rs:46:8
[INFO] [stderr]    |
[INFO] [stderr] 46 |     if chars.len() == 0 {
[INFO] [stderr]    |        ^^^^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `chars.is_empty()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::len_zero)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the slice
[INFO] [stderr]   --> src/math.rs:57:27
[INFO] [stderr]    |
[INFO] [stderr] 57 |     let s: String = chars.into_iter().collect();
[INFO] [stderr]    |                           ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::into_iter_on_ref)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]  --> src/main.rs:5:11
[INFO] [stderr]   |
[INFO] [stderr] 5 |     match std::env::args().skip(1).next() {
[INFO] [stderr]   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(clippy::iter_skip_next)] on by default
[INFO] [stderr]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]   --> src/main.rs:24:19
[INFO] [stderr]    |
[INFO] [stderr] 24 |     let s = match std::env::args().skip(2).next() {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]   --> src/main.rs:47:19
[INFO] [stderr]    |
[INFO] [stderr] 47 |     let n = match std::env::args().skip(2).next() {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]   --> src/main.rs:63:19
[INFO] [stderr]    |
[INFO] [stderr] 63 |     let s = match std::env::args().skip(2).next() {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]   --> src/program.rs:39:24
[INFO] [stderr]    |
[INFO] [stderr] 39 | pub fn str_to_chars(s: &String) -> Vec<char> {
[INFO] [stderr]    |                        ^^^^^^^ help: change this to: `&str`
[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: length comparison to zero
[INFO] [stderr]   --> src/program.rs:46:8
[INFO] [stderr]    |
[INFO] [stderr] 46 |     if chars.len() == 0 {
[INFO] [stderr]    |        ^^^^^^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `chars.is_empty()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::len_zero)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the slice
[INFO] [stderr]   --> src/math.rs:57:27
[INFO] [stderr]    |
[INFO] [stderr] 57 |     let s: String = chars.into_iter().collect();
[INFO] [stderr]    |                           ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::into_iter_on_ref)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]  --> src/main.rs:5:11
[INFO] [stderr]   |
[INFO] [stderr] 5 |     match std::env::args().skip(1).next() {
[INFO] [stderr]   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(clippy::iter_skip_next)] on by default
[INFO] [stderr]   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]   --> src/main.rs:24:19
[INFO] [stderr]    |
[INFO] [stderr] 24 |     let s = match std::env::args().skip(2).next() {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]   --> src/main.rs:47:19
[INFO] [stderr]    |
[INFO] [stderr] 47 |     let n = match std::env::args().skip(2).next() {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr] warning: called `skip(x).next()` on an iterator. This is more succinctly expressed by calling `nth(x)`
[INFO] [stderr]   --> src/main.rs:63:19
[INFO] [stderr]    |
[INFO] [stderr] 63 |     let s = match std::env::args().skip(2).next() {
[INFO] [stderr]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#iter_skip_next
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.36s
[INFO] running `"docker" "inspect" "4bde20840d8d79d8b0d74b4a11478880762308f409c59a33a42168b4f4a62d7e"`
[INFO] running `"docker" "rm" "-f" "4bde20840d8d79d8b0d74b4a11478880762308f409c59a33a42168b4f4a62d7e"`
[INFO] [stdout] 4bde20840d8d79d8b0d74b4a11478880762308f409c59a33a42168b4f4a62d7e