[INFO] updating cached repository https://github.com/modulitos/CtCI-rust
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/mnt/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 48bbe8f02fa15654255784d482ce329f3328f8de
[INFO] checking modulitos/CtCI-rust against try#e689e5eaefe96e6dc3ed5bb629c521b7d207aff7 for pr-64398
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2FCtCI-rust" "work/builds/worker-3/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/modulitos/CtCI-rust on toolchain e689e5eaefe96e6dc3ed5bb629c521b7d207aff7-alt
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+e689e5eaefe96e6dc3ed5bb629c521b7d207aff7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/modulitos/CtCI-rust
[INFO] finished tweaking git repo https://github.com/modulitos/CtCI-rust
[INFO] tweaked toml for git repo https://github.com/modulitos/CtCI-rust written to work/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/modulitos/CtCI-rust already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/cargo-home/bin/cargo" "+e689e5eaefe96e6dc3ed5bb629c521b7d207aff7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/mnt/big/crater/work/builds/worker-3/source:/opt/rustwide/workdir:ro,Z" "-v" "/mnt/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+e689e5eaefe96e6dc3ed5bb629c521b7d207aff7-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 644cc7eb00201eecb6b24b2686a3f0174b440cd4a8078783f9eb197dae215354
[INFO] running `"docker" "start" "-a" "644cc7eb00201eecb6b24b2686a3f0174b440cd4a8078783f9eb197dae215354"`
[INFO] [stderr]     Checking rust-solutions v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `super::List`
[INFO] [stderr]    --> src/linked_list/second.rs:167:9
[INFO] [stderr]     |
[INFO] [stderr] 167 |     use super::List;
[INFO] [stderr]     |         ^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/linked_list/third.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/linked_list/fifth.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/linked_list/refcell_singly.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]    --> src/stack.rs:115:9
[INFO] [stderr]     |
[INFO] [stderr] 115 |     use super::*;
[INFO] [stderr]     |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]    --> src/binary_search_tree.rs:124:9
[INFO] [stderr]     |
[INFO] [stderr] 124 |     use super::*;
[INFO] [stderr]     |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Ord`, `Ordering`
[INFO] [stderr]  --> src/graph.rs:1:16
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::cmp::{Ord, Ordering};
[INFO] [stderr]   |                ^^^  ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]    --> src/graph.rs:178:9
[INFO] [stderr]     |
[INFO] [stderr] 178 |     use super::*;
[INFO] [stderr]     |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]   --> src/binary_tree.rs:43:9
[INFO] [stderr]    |
[INFO] [stderr] 43 |     use super::*;
[INFO] [stderr]    |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]   --> src/binary_tree_refcell.rs:51:9
[INFO] [stderr]    |
[INFO] [stderr] 51 |     use super::*;
[INFO] [stderr]    |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]    --> src/binary_search_tree_refcell.rs:128:9
[INFO] [stderr]     |
[INFO] [stderr] 128 |     use super::*;
[INFO] [stderr]     |         ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/linked_list/third.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::collections::HashSet`
[INFO] [stderr]  --> src/linked_list/fifth.rs:3:5
[INFO] [stderr]   |
[INFO] [stderr] 3 | use std::collections::HashSet;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused imports: `Ord`, `Ordering`
[INFO] [stderr]  --> src/graph.rs:1:16
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::cmp::{Ord, Ordering};
[INFO] [stderr]   |                ^^^  ^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/linked_list/second.rs:67:5
[INFO] [stderr]    |
[INFO] [stderr] 67 |     pub fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `into_iter`
[INFO] [stderr]   --> src/linked_list/second.rs:71:5
[INFO] [stderr]    |
[INFO] [stderr] 71 |     pub fn into_iter(self) -> IntoIter<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `iter`
[INFO] [stderr]   --> src/linked_list/second.rs:76:5
[INFO] [stderr]    |
[INFO] [stderr] 76 |     pub fn iter(&self) -> Iter<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `iter_mut`
[INFO] [stderr]   --> src/linked_list/second.rs:84:5
[INFO] [stderr]    |
[INFO] [stderr] 84 |     pub fn iter_mut(&mut self) -> IterMut<'_, T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `push`
[INFO] [stderr]   --> src/linked_list/second.rs:90:5
[INFO] [stderr]    |
[INFO] [stderr] 90 |     pub fn push(&mut self, elem: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `peek`
[INFO] [stderr]    --> src/linked_list/second.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     pub fn peek(&self) -> Option<&T> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `peek_mut`
[INFO] [stderr]    --> src/linked_list/second.rs:123:5
[INFO] [stderr]     |
[INFO] [stderr] 123 |     pub fn peek_mut(&mut self) -> Option<&mut T> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/linked_list/third.rs:21:5
[INFO] [stderr]    |
[INFO] [stderr] 21 |     pub fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `append`
[INFO] [stderr]   --> src/linked_list/third.rs:25:5
[INFO] [stderr]    |
[INFO] [stderr] 25 |     pub fn append(&mut self, elem: T) -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `tail`
[INFO] [stderr]   --> src/linked_list/third.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     pub fn tail(&self) -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `head`
[INFO] [stderr]   --> src/linked_list/third.rs:40:5
[INFO] [stderr]    |
[INFO] [stderr] 40 |     pub fn head(&self) -> Option<&T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `iter`
[INFO] [stderr]    --> src/linked_list/third.rs:107:5
[INFO] [stderr]     |
[INFO] [stderr] 107 |     pub fn iter(&self) -> Iter<'_, T> {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/linked_list/fourth.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 |     fn new(elem: T) -> Rc<RefCell<Self>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/linked_list/fourth.rs:29:5
[INFO] [stderr]    |
[INFO] [stderr] 29 |     pub fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `push_front`
[INFO] [stderr]   --> src/linked_list/fourth.rs:35:5
[INFO] [stderr]    |
[INFO] [stderr] 35 |     pub fn push_front(&mut self, elem: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `peek_front`
[INFO] [stderr]   --> src/linked_list/fourth.rs:76:5
[INFO] [stderr]    |
[INFO] [stderr] 76 |     pub fn peek_front(&self) -> Option<Ref<T>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: field is never used: `prev`
[INFO] [stderr]   --> src/linked_list/brandon.rs:25:5
[INFO] [stderr]    |
[INFO] [stderr] 25 |     prev: Option<NodeRef<T>>,
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `tail`
[INFO] [stderr]   --> src/linked_list/brandon.rs:39:5
[INFO] [stderr]    |
[INFO] [stderr] 39 |     fn tail(node: &NodeRef<T>) -> Option<NodeRef<T>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `remove`
[INFO] [stderr]   --> src/linked_list/brandon.rs:46:5
[INFO] [stderr]    |
[INFO] [stderr] 46 |     fn remove(&mut self) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/linked_list/brandon.rs:64:5
[INFO] [stderr]    |
[INFO] [stderr] 64 |     fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `append`
[INFO] [stderr]   --> src/linked_list/brandon.rs:68:5
[INFO] [stderr]    |
[INFO] [stderr] 68 |     fn append(&mut self, new_value: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `tail`
[INFO] [stderr]   --> src/linked_list/brandon.rs:85:5
[INFO] [stderr]    |
[INFO] [stderr] 85 |     fn tail(&self) -> Option<NodeRef<T>> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `iter`
[INFO] [stderr]   --> src/linked_list/brandon.rs:96:5
[INFO] [stderr]    |
[INFO] [stderr] 96 |     fn iter(&self) -> Iter<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `list_has_duplicates`
[INFO] [stderr]    --> src/linked_list/brandon.rs:102:5
[INFO] [stderr]     |
[INFO] [stderr] 102 |     fn list_has_duplicates(&self) -> bool {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `remove_duplicates`
[INFO] [stderr]    --> src/linked_list/brandon.rs:117:5
[INFO] [stderr]     |
[INFO] [stderr] 117 |     fn remove_duplicates(&mut self) {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `main`
[INFO] [stderr]    --> src/linked_list/brandon.rs:228:1
[INFO] [stderr]     |
[INFO] [stderr] 228 | fn main() {
[INFO] [stderr]     | ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `new`
[INFO] [stderr]   --> src/linked_list/fifth.rs:24:5
[INFO] [stderr]    |
[INFO] [stderr] 24 |     pub fn new() -> Self {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `push`
[INFO] [stderr]   --> src/linked_list/fifth.rs:31:5
[INFO] [stderr]    |
[INFO] [stderr] 31 |     pub fn push(&mut self, elem: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `pop`
[INFO] [stderr]   --> src/linked_list/fifth.rs:53:5
[INFO] [stderr]    |
[INFO] [stderr] 53 |     pub fn pop(&mut self) -> Option<T> {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `a`
[INFO] [stderr]   --> src/bin/ch3-p1_three-in-one.rs:89:13
[INFO] [stderr]    |
[INFO] [stderr] 89 |         let a: ThreeStacks<u64> = ThreeStacks::new();
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_a`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `grow`
[INFO] [stderr]   --> src/bin/ch3-p1_three-in-one.rs:70:5
[INFO] [stderr]    |
[INFO] [stderr] 70 |     fn grow(&mut self, min_cap: usize) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:129:9
[INFO] [stderr]     |
[INFO] [stderr] 129 |         s.push(1, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:136:9
[INFO] [stderr]     |
[INFO] [stderr] 136 |         s.push(1, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:137:9
[INFO] [stderr]     |
[INFO] [stderr] 137 |         s.push(2, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:138:9
[INFO] [stderr]     |
[INFO] [stderr] 138 |         s.push(3, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:144:9
[INFO] [stderr]     |
[INFO] [stderr] 144 |         s.push(1, 1).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:145:9
[INFO] [stderr]     |
[INFO] [stderr] 145 |         s.push(2, 1).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:146:9
[INFO] [stderr]     |
[INFO] [stderr] 146 |         s.push(3, 1).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:152:9
[INFO] [stderr]     |
[INFO] [stderr] 152 |         s.push(1, 2).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:153:9
[INFO] [stderr]     |
[INFO] [stderr] 153 |         s.push(2, 2).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:154:9
[INFO] [stderr]     |
[INFO] [stderr] 154 |         s.push(3, 2).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:165:9
[INFO] [stderr]     |
[INFO] [stderr] 165 |         s.push(1, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:166:9
[INFO] [stderr]     |
[INFO] [stderr] 166 |         s.push(2, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:167:9
[INFO] [stderr]     |
[INFO] [stderr] 167 |         s.push(3, 0).is_ok();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `std::result::Result::<T, E>::is_err` that must be used
[INFO] [stderr]    --> src/bin/ch3-p1_three-in-one.rs:168:9
[INFO] [stderr]     |
[INFO] [stderr] 168 |         s.push(4, 0).is_err();
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: if you intended to assert that this is err, consider `.unwrap_err()` instead
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `partition`
[INFO] [stderr]   --> src/bin/ch2-p4_partition.rs:95:5
[INFO] [stderr]    |
[INFO] [stderr] 95 |     fn partition(&mut self, partition_value: T) {
[INFO] [stderr]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: method is never used: `verify_partition`
[INFO] [stderr]    --> src/bin/ch2-p4_partition.rs:113:5
[INFO] [stderr]     |
[INFO] [stderr] 113 |     fn verify_partition(&mut self, value: T) -> bool {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]   --> src/bin/ch4-p1_route-between-nodes.rs:68:9
[INFO] [stderr]    |
[INFO] [stderr] 68 |     use super::*;
[INFO] [stderr]    |         ^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0601]: `main` function not found in crate `ch4_p1_route_between_nodes`
[INFO] [stderr]   |
[INFO] [stderr]   = note: consider adding a `main` function to `src/bin/ch4-p1_route-between-nodes.rs`
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `is_rotation`
[INFO] [stderr]   --> src/bin/ch1-p9_string-rotation.rs:10:1
[INFO] [stderr]    |
[INFO] [stderr] 10 | fn is_rotation(s1: &str, s2: &str) -> bool {
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0601`.
[INFO] [stderr] error: Could not compile `rust-solutions`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] warning: unused import: `super::*`
[INFO] [stderr]   --> src/bin/ch3-p1_three-in-one.rs:84:9
[INFO] [stderr]    |
[INFO] [stderr] 84 |     use super::*;
[INFO] [stderr]    |         ^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0601]: `main` function not found in crate `ch3_p1_three_in_one`
[INFO] [stderr]   |
[INFO] [stderr]   = note: consider adding a `main` function to `src/bin/ch3-p1_three-in-one.rs`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0601`.
[INFO] [stderr] error: Could not compile `rust-solutions`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/stack.rs:153:13
[INFO] [stderr]     |
[INFO] [stderr] 153 |         let mut s: Stack<u64> = Stack::new();
[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: method is never used: `list_has_duplicates`
[INFO] [stderr]    --> src/linked_list/brandon.rs:102:5
[INFO] [stderr]     |
[INFO] [stderr] 102 |     fn list_has_duplicates(&self) -> bool {
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `main`
[INFO] [stderr]    --> src/linked_list/brandon.rs:228:1
[INFO] [stderr]     |
[INFO] [stderr] 228 | fn main() {
[INFO] [stderr]     | ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r`
[INFO] [stderr]   --> src/bin/ch4-p11_random-node.rs:91:24
[INFO] [stderr]    |
[INFO] [stderr] 91 |         (Some(l), Some(r)) => {
[INFO] [stderr]    |                        ^ help: consider prefixing with an underscore: `_r`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "644cc7eb00201eecb6b24b2686a3f0174b440cd4a8078783f9eb197dae215354"`
[INFO] running `"docker" "rm" "-f" "644cc7eb00201eecb6b24b2686a3f0174b440cd4a8078783f9eb197dae215354"`
[INFO] [stdout] 644cc7eb00201eecb6b24b2686a3f0174b440cd4a8078783f9eb197dae215354