[INFO] cloning repository https://github.com/clD11/rust-katas
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/clD11/rust-katas" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FclD11%2Frust-katas", kill_on_drop: false }`
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[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3bea90de5d0ae718c39418469d908a09c934ab8f
[INFO] checking clD11/rust-katas against master#0d56e340472882fa673d4b98d0802b9a799879d0 for pr-101692
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FclD11%2Frust-katas" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/clD11/rust-katas on toolchain 0d56e340472882fa673d4b98d0802b9a799879d0
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[INFO] finished tweaking git repo https://github.com/clD11/rust-katas
[INFO] tweaked toml for git repo https://github.com/clD11/rust-katas written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/clD11/rust-katas already has a lockfile, it will not be regenerated
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[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.1
[INFO] [stderr]    Compiling syn v1.0.96
[INFO] [stderr]    Compiling futures-core v0.3.21
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]     Checking pin-project-lite v0.2.9
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]     Checking futures-io v0.3.21
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking cache-padded v1.2.0
[INFO] [stderr]     Checking slab v0.4.6
[INFO] [stderr]     Checking once_cell v1.12.0
[INFO] [stderr]     Checking waker-fn v1.1.0
[INFO] [stderr]     Checking fastrand v1.7.0
[INFO] [stderr]     Checking parking v2.0.0
[INFO] [stderr]     Checking event-listener v2.5.2
[INFO] [stderr]    Compiling futures-task v0.3.21
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling futures-channel v0.3.21
[INFO] [stderr]     Checking async-task v4.2.0
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]     Checking futures-sink v0.3.21
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling futures-util v0.3.21
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[INFO] [stderr]     Checking ppv-lite86 v0.2.6
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking concurrent-queue v1.2.2
[INFO] [stderr]    Compiling value-bag v1.0.0-alpha.9
[INFO] [stderr]     Checking async-lock v2.5.0
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[INFO] [stderr]     Checking socket2 v0.4.4
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking async-executor v1.4.1
[INFO] [stderr]     Checking blocking v1.2.0
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]    Compiling ctor v0.1.22
[INFO] [stderr]    Compiling futures-macro v0.3.21
[INFO] [stderr]     Checking polling v2.2.0
[INFO] [stderr]     Checking kv-log-macro v1.0.7
[INFO] [stderr]     Checking async-io v1.7.0
[INFO] [stderr]     Checking async-global-executor v2.1.0
[INFO] [stderr]     Checking async-std v1.11.0
[INFO] [stderr]     Checking futures-executor v0.3.21
[INFO] [stderr]     Checking futures v0.3.21
[INFO] [stderr]     Checking rust-katas v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `futures::executor::block_on`
[INFO] [stdout]  --> src/multithreading/async_book.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use futures::executor::block_on;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `BoxFuture`, `FutureExt`, `sync::atomic::compiler_fence`, `sync_channel`, `waker_ref`
[INFO] [stdout]   --> src/multithreading/async_book.rs:6:18
[INFO] [stdout]    |
[INFO] [stdout] 6  |         future::{BoxFuture, FutureExt},
[INFO] [stdout]    |                  ^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout] 7  |         task::{waker_ref, ArcWake},
[INFO] [stdout]    |                ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 12 |         sync::atomic::compiler_fence,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 13 |         sync::mpsc::{sync_channel, Receiver, SyncSender},
[INFO] [stdout]    |                      ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `datastore` should have an upper camel case name
[INFO] [stdout]  --> src/multithreading/concurrent.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct datastore {
[INFO] [stdout]   |        ^^^^^^^^^ help: convert the identifier to upper camel case: `Datastore`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::string::String`
[INFO] [stdout]  --> src/rust_book/slice.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::string::String;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `BoxFuture`, `FutureExt`, `sync::atomic::compiler_fence`, `sync_channel`, `waker_ref`
[INFO] [stdout]   --> src/multithreading/async_book.rs:6:18
[INFO] [stdout]    |
[INFO] [stdout] 6  |         future::{BoxFuture, FutureExt},
[INFO] [stdout]    |                  ^^^^^^^^^  ^^^^^^^^^
[INFO] [stdout] 7  |         task::{waker_ref, ArcWake},
[INFO] [stdout]    |                ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 12 |         sync::atomic::compiler_fence,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 13 |         sync::mpsc::{sync_channel, Receiver, SyncSender},
[INFO] [stdout]    |                      ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `datastore` should have an upper camel case name
[INFO] [stdout]  --> src/multithreading/concurrent.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct datastore {
[INFO] [stdout]   |        ^^^^^^^^^ help: convert the identifier to upper camel case: `Datastore`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ArcWake`
[INFO] [stdout]  --> src/multithreading/async_book.rs:7:27
[INFO] [stdout]   |
[INFO] [stdout] 7 |         task::{waker_ref, ArcWake},
[INFO] [stdout]   |                           ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_number_deletions` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/alternating_characters.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn count_number_deletions(input: String) -> u32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `append_and_delete` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/append_and_delete.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn append_and_delete(initial: &str, desired: &str, operation: usize) -> &'static str {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `adj` is never read
[INFO] [stdout]  --> src/hackerrank/problem_solving/breadth_first_search_shortest_reach.rs:3:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | struct Graph {
[INFO] [stdout]   |        ----- field in this struct
[INFO] [stdout] 3 |     adj: Vec<Vec<usize>>,
[INFO] [stdout]   |     ^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Graph` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `build` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/breadth_first_search_shortest_reach.rs:7:8
[INFO] [stdout]   |
[INFO] [stdout] 7 |     fn build(v: usize) -> Graph {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `add_edge` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/breadth_first_search_shortest_reach.rs:14:8
[INFO] [stdout]    |
[INFO] [stdout] 14 |     fn add_edge(&mut self, v: usize, w: usize) {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `adj` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/breadth_first_search_shortest_reach.rs:19:8
[INFO] [stdout]    |
[INFO] [stdout] 19 |     fn adj(&mut self, v: usize) -> &Vec<usize> {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `encrypt` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/caesar_cipher.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn encrypt(message: &str, rotate: u8) -> String {
[INFO] [stdout]   |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `cat_and_mouse` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/cat_mouse.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn cat_and_mouse(x: i32, y: i32, z: i32) -> &'static str {
[INFO] [stdout]   |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `sum` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/distinct_pairs.rs:4:8
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub fn sum(nums: &[u32], target: u32) -> u32 {
[INFO] [stdout]   |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `divisible_sum_pairs` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/divisible_sum_pairs.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn divisible_sum_pairs(n: usize, k: u32, ar: &[u32]) -> u32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fair_rations` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/fair_rations.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn fair_rations(arr: &[u32]) -> &'static str {
[INFO] [stdout]   |        ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `find_digits` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/find_digits.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub fn find_digits(n: u32) -> u32 {
[INFO] [stdout]   |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `is_divisible_by` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/fizz_buzz.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn is_divisible_by(lhs: u32, rhs: u32) -> bool {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fizzbuzz` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/fizz_buzz.rs:8:4
[INFO] [stdout]   |
[INFO] [stdout] 8 | fn fizzbuzz(n: u32) {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fizzbuzz_to` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/fizz_buzz.rs:20:4
[INFO] [stdout]    |
[INFO] [stdout] 20 | fn fizzbuzz_to(n: u32) {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `fizzbuzz_two` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/fizz_buzz_two.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn fizzbuzz_two() {
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `funny_string` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/funny_string.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn funny_string(input: &str) -> &'static str {
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `has_hackerrank` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/hackerrank_string.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn has_hackerrank(input: &str) -> &'static str {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `what_flavours` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/ice_cream_parlor.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn what_flavours(flavours: &Vec<u32>, money: &u32) -> [u32; 2] {
[INFO] [stdout]   |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_anagram` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/making_anagrams.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn make_anagram(a: &str, b: &str) -> u32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `count_difference` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/mars_exploration.rs:2:4
[INFO] [stdout]   |
[INFO] [stdout] 2 | fn count_difference(input: &str) -> u32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `missing_numbers` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/missing_numbers.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn missing_numbers(arr: &Vec<u32>, brr: &Vec<u32>) -> Vec<u32> {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `to_roman_numeral` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/number_converter.rs:29:8
[INFO] [stdout]    |
[INFO] [stdout] 29 | pub fn to_roman_numeral(number: u32) -> String {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `ArcWake`
[INFO] [stdout]  --> src/multithreading/async_book.rs:7:27
[INFO] [stdout]   |
[INFO] [stdout] 7 |         task::{waker_ref, ArcWake},
[INFO] [stdout]   |                           ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `find_pairs_to_target` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/pairs.rs:3:8
[INFO] [stdout]   |
[INFO] [stdout] 3 | pub fn find_pairs_to_target(input: Vec<u32>, target: u32) -> u32 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: irrefutable `if let` pattern
[INFO] [stdout]  --> src/rust_book/defining_enums.rs:9:8
[INFO] [stdout]   |
[INFO] [stdout] 9 |     if let IpAddrKind::V4(actual) = v4 {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(irrefutable_let_patterns)]` on by default
[INFO] [stdout]   = note: this pattern will always match, so the `if let` is useless
[INFO] [stdout]   = help: consider replacing the `if let` with a `let`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `pairs_boxed` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/pairs.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn pairs_boxed() -> Box<[u32; 2]> {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `pairs_vec` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/pairs.rs:27:4
[INFO] [stdout]    |
[INFO] [stdout] 27 | fn pairs_vec() -> Vec<[u32; 2]> {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `find_beautiful_number` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/separate_numbers.rs:3:4
[INFO] [stdout]   |
[INFO] [stdout] 3 | fn find_beautiful_number(input: &str) -> String {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `balanced_sums_count` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/sherlock_and_array.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn balanced_sums_count(arr: &Vec<u32>) -> &str {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `balanced_sums` is never used
[INFO] [stdout]   --> src/hackerrank/problem_solving/sherlock_and_array.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | fn balanced_sums(arr: &Vec<u32>) -> &str {
[INFO] [stdout]    |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `two_characters` is never used
[INFO] [stdout]  --> src/hackerrank/problem_solving/two_characters.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn two_characters(input: &str) -> i32 {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `useful` is never used
[INFO] [stdout]  --> src/hackerrank/utils.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn useful() {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `remove_newline` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn remove_newline(line: &str) -> String {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_lines` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn read_lines() {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_u8` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:47:4
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn read_u8() {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_vec` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:58:8
[INFO] [stdout]    |
[INFO] [stdout] 58 | pub fn read_vec() -> Vec<String> {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hello_world` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:22:10
[INFO] [stdout]    |
[INFO] [stdout] 22 | async fn hello_world() {
[INFO] [stdout]    |          ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `learn_song` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:26:10
[INFO] [stdout]    |
[INFO] [stdout] 26 | async fn learn_song() -> String {
[INFO] [stdout]    |          ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `sing_song` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:33:10
[INFO] [stdout]    |
[INFO] [stdout] 33 | async fn sing_song(song: String) {
[INFO] [stdout]    |          ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `learn_and_sing` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:37:10
[INFO] [stdout]    |
[INFO] [stdout] 37 | async fn learn_and_sing() {
[INFO] [stdout]    |          ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `dance` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:42:10
[INFO] [stdout]    |
[INFO] [stdout] 42 | async fn dance() {
[INFO] [stdout]    |          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `perform` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:49:10
[INFO] [stdout]    |
[INFO] [stdout] 49 | async fn perform() {
[INFO] [stdout]    |          ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Executor` is never constructed
[INFO] [stdout]    --> src/multithreading/async_book.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 | struct Executor {
[INFO] [stdout]     |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `task_sender` is never read
[INFO] [stdout]    --> src/multithreading/async_book.rs:108:5
[INFO] [stdout]     |
[INFO] [stdout] 107 | struct Spawner {
[INFO] [stdout]     |        ------- field in this struct
[INFO] [stdout] 108 |     task_sender: SyncSender<Arc<Task>>,
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `Spawner` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:67:12
[INFO] [stdout]    |
[INFO] [stdout] 67 |     pub fn new(duration: Duration) -> TimerFuture {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `datastore` is never constructed
[INFO] [stdout]  --> src/multithreading/concurrent.rs:1:8
[INFO] [stdout]   |
[INFO] [stdout] 1 | struct datastore {
[INFO] [stdout]   |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `mask_character` is never used
[INFO] [stdout]  --> src/rust_book/char_strings.rs:1:4
[INFO] [stdout]   |
[INFO] [stdout] 1 | fn mask_character(target: &str, input: &str) -> String {
[INFO] [stdout]   |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IpAddrKind` is never used
[INFO] [stdout]  --> src/rust_book/defining_enums.rs:1:6
[INFO] [stdout]   |
[INFO] [stdout] 1 | enum IpAddrKind {
[INFO] [stdout]   |      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `guess` is never used
[INFO] [stdout]  --> src/rust_book/guessing_game.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn guess() {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `width` and `height` are never read
[INFO] [stdout]  --> src/rust_book/rectangle.rs:7:5
[INFO] [stdout]   |
[INFO] [stdout] 6 | struct Rectangle {
[INFO] [stdout]   |        --------- fields in this struct
[INFO] [stdout] 7 |     width: i32,
[INFO] [stdout]   |     ^^^^^
[INFO] [stdout] 8 |     height: i32,
[INFO] [stdout]   |     ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `Rectangle` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `square` is never used
[INFO] [stdout]   --> src/rust_book/rectangle.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 |     fn square(d: i32) -> Rectangle {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `area` is never used
[INFO] [stdout]   --> src/rust_book/rectangle.rs:20:8
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fn area(&self) -> i32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `can_hold` is never used
[INFO] [stdout]   --> src/rust_book/rectangle.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 24 |     fn can_hold(&self, rectangle: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `find_first_word` is never used
[INFO] [stdout]  --> src/rust_book/slice.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | pub fn find_first_word(s: &str) -> &str {
[INFO] [stdout]   |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 58 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `useful` is never used
[INFO] [stdout]  --> src/hackerrank/utils.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn useful() {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `remove_newline` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:21:4
[INFO] [stdout]    |
[INFO] [stdout] 21 | fn remove_newline(line: &str) -> String {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_lines` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:36:4
[INFO] [stdout]    |
[INFO] [stdout] 36 | fn read_lines() {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_u8` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:47:4
[INFO] [stdout]    |
[INFO] [stdout] 47 | fn read_u8() {
[INFO] [stdout]    |    ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `read_vec` is never used
[INFO] [stdout]   --> src/hackerrank/utils.rs:58:8
[INFO] [stdout]    |
[INFO] [stdout] 58 | pub fn read_vec() -> Vec<String> {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Executor` is never constructed
[INFO] [stdout]    --> src/multithreading/async_book.rs:102:8
[INFO] [stdout]     |
[INFO] [stdout] 102 | struct Executor {
[INFO] [stdout]     |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `task_sender` is never read
[INFO] [stdout]    --> src/multithreading/async_book.rs:108:5
[INFO] [stdout]     |
[INFO] [stdout] 107 | struct Spawner {
[INFO] [stdout]     |        ------- field in this struct
[INFO] [stdout] 108 |     task_sender: SyncSender<Arc<Task>>,
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `Spawner` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/multithreading/async_book.rs:67:12
[INFO] [stdout]    |
[INFO] [stdout] 67 |     pub fn new(duration: Duration) -> TimerFuture {
[INFO] [stdout]    |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `guess` is never used
[INFO] [stdout]  --> src/rust_book/guessing_game.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | pub fn guess() {
[INFO] [stdout]   |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 13 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 19.22s
[INFO] running `Command { std: "docker" "inspect" "5ec477361608dc4dd705e2679c390d566d9b741bdb17885203727f33a42a97ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ec477361608dc4dd705e2679c390d566d9b741bdb17885203727f33a42a97ab", kill_on_drop: false }`
[INFO] [stdout] 5ec477361608dc4dd705e2679c390d566d9b741bdb17885203727f33a42a97ab