[INFO] cloning repository https://github.com/chrisp9/rust_exploration
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/chrisp9/rust_exploration" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchrisp9%2Frust_exploration", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchrisp9%2Frust_exploration'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 08c29e33beb024b8d3a51e551724e279bf8a4a9f
[INFO] building chrisp9/rust_exploration against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fchrisp9%2Frust_exploration" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/chrisp9/rust_exploration on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/chrisp9/rust_exploration
[INFO] finished tweaking git repo https://github.com/chrisp9/rust_exploration
[INFO] tweaked toml for git repo https://github.com/chrisp9/rust_exploration written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/chrisp9/rust_exploration already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3ae6cf079600bc68e61e308e1dd3d3fec645c374514e627d26ca471bc50e772c
[INFO] running `Command { std: "docker" "start" "-a" "3ae6cf079600bc68e61e308e1dd3d3fec645c374514e627d26ca471bc50e772c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3ae6cf079600bc68e61e308e1dd3d3fec645c374514e627d26ca471bc50e772c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3ae6cf079600bc68e61e308e1dd3d3fec645c374514e627d26ca471bc50e772c", kill_on_drop: false }`
[INFO] [stdout] 3ae6cf079600bc68e61e308e1dd3d3fec645c374514e627d26ca471bc50e772c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid -Dtail-expr-drop-order" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d35c75d01d0a1df8489a5ffb8f464b9ddfda2c23f84d388138abc5585eaaf5a5
[INFO] running `Command { std: "docker" "start" "-a" "d35c75d01d0a1df8489a5ffb8f464b9ddfda2c23f84d388138abc5585eaaf5a5", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stderr]    Compiling libc v0.2.43
[INFO] [stderr]    Compiling rand v0.4.3
[INFO] [stderr]    Compiling rand v0.3.22
[INFO] [stderr]    Compiling rust_exploration v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]    --> src/main.rs:177:45
[INFO] [stdout]     |
[INFO] [stdout] 177 |     let mut expensive_result = Cacher::new(|num| {
[INFO] [stdout]     |                                             ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `equal_to_x`
[INFO] [stdout]    --> src/main.rs:212:9
[INFO] [stdout]     |
[INFO] [stdout] 212 |     let equal_to_x = |z : u32| z == x;
[INFO] [stdout]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_equal_to_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:213:9
[INFO] [stdout]     |
[INFO] [stdout] 213 |     let y = 4;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `res`
[INFO] [stdout]    --> src/main.rs:229:9
[INFO] [stdout]     |
[INFO] [stdout] 229 |     let res: Vec<_> = v1.iter().map(|x| x + 1).collect();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_res`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]    --> src/main.rs:236:9
[INFO] [stdout]     |
[INFO] [stdout] 236 |     let total: i32 = v1_iter.sum();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> src/main.rs:289:9
[INFO] [stdout]     |
[INFO] [stdout] 289 |     let item = map.get(&key).unwrap();
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> src/main.rs:296:9
[INFO] [stdout]     |
[INFO] [stdout] 296 |     let s3 = s1 + &s2;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:306:9
[INFO] [stdout]     |
[INFO] [stdout] 306 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `third`
[INFO] [stdout]    --> src/main.rs:309:9
[INFO] [stdout]     |
[INFO] [stdout] 309 |     let third: &i32 = &v[2];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_third`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_number`
[INFO] [stdout]    --> src/main.rs:372:9
[INFO] [stdout]     |
[INFO] [stdout] 372 |     let some_number = Some(5);
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_string`
[INFO] [stdout]    --> src/main.rs:373:9
[INFO] [stdout]     |
[INFO] [stdout] 373 |     let some_string = Some("A string");
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `absent_number`
[INFO] [stdout]    --> src/main.rs:375:9
[INFO] [stdout]     |
[INFO] [stdout] 375 |     let absent_number : Option<i32> = None;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `rect3`
[INFO] [stdout]    --> src/main.rs:387:9
[INFO] [stdout]     |
[INFO] [stdout] 387 |     let rect3 = Rectangle {width: 60, height: 45};
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_rect3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Pair` is never constructed
[INFO] [stdout]   --> src/main.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct Pair<T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 23 | impl<T> Pair<T> {
[INFO] [stdout]    | --------------- associated function in this implementation
[INFO] [stdout] 24 |     fn new(x: T, y: T) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `cmp_display` is never used
[INFO] [stdout]   --> src/main.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 32 | impl<T: Display + PartialOrd> Pair<T> {
[INFO] [stdout]    | ------------------------------------- method in this implementation
[INFO] [stdout] 33 |     fn cmp_display(&self) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `User` is never constructed
[INFO] [stdout]   --> src/main.rs:42:8
[INFO] [stdout]    |
[INFO] [stdout] 42 | struct User {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rectangle` is never constructed
[INFO] [stdout]   --> src/main.rs:49:8
[INFO] [stdout]    |
[INFO] [stdout] 49 | struct Rectangle {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `area`, `can_hold`, and `square` are never used
[INFO] [stdout]   --> src/main.rs:55:8
[INFO] [stdout]    |
[INFO] [stdout] 54 | impl Rectangle {
[INFO] [stdout]    | -------------- associated items in this implementation
[INFO] [stdout] 55 |     fn area(&self) -> u32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 59 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 63 |     fn square(size: u32) -> Rectangle {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IpAddrKind` is never used
[INFO] [stdout]   --> src/main.rs:68:6
[INFO] [stdout]    |
[INFO] [stdout] 68 | enum IpAddrKind {
[INFO] [stdout]    |      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `UsState` is never used
[INFO] [stdout]   --> src/main.rs:74:6
[INFO] [stdout]    |
[INFO] [stdout] 74 | enum UsState {
[INFO] [stdout]    |      ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Coin` is never used
[INFO] [stdout]   --> src/main.rs:80:6
[INFO] [stdout]    |
[INFO] [stdout] 80 | enum Coin {
[INFO] [stdout]    |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Message` is never used
[INFO] [stdout]   --> src/main.rs:87:6
[INFO] [stdout]    |
[INFO] [stdout] 87 | enum Message {
[INFO] [stdout]    |      ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `call` is never used
[INFO] [stdout]   --> src/main.rs:95:8
[INFO] [stdout]    |
[INFO] [stdout] 94 | impl Message {
[INFO] [stdout]    | ------------ method in this implementation
[INFO] [stdout] 95 |     fn call(&self) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `largest` is never used
[INFO] [stdout]    --> src/main.rs:100:5
[INFO] [stdout]     |
[INFO] [stdout] 100 |  fn largest<T : PartialOrd>(list: &[T]) -> &T {
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Point` is never constructed
[INFO] [stdout]    --> src/main.rs:112:8
[INFO] [stdout]     |
[INFO] [stdout] 112 | struct Point<T> {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Shoe` is never constructed
[INFO] [stdout]    --> src/main.rs:118:8
[INFO] [stdout]     |
[INFO] [stdout] 118 | struct Shoe {
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `shoes_in_my_size` is never used
[INFO] [stdout]    --> src/main.rs:123:4
[INFO] [stdout]     |
[INFO] [stdout] 123 | fn shoes_in_my_size(shoes: Vec<Shoe>, shoe_size: u32) -> Vec<Shoe> {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `simulated_expensive_calculation` is never used
[INFO] [stdout]    --> src/main.rs:204:4
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `closure_capturing_context` is never used
[INFO] [stdout]    --> src/main.rs:210:4
[INFO] [stdout]     |
[INFO] [stdout] 210 | fn closure_capturing_context() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `iterators` is never used
[INFO] [stdout]    --> src/main.rs:217:4
[INFO] [stdout]     |
[INFO] [stdout] 217 | fn iterators() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `iterator_map` is never used
[INFO] [stdout]    --> src/main.rs:226:4
[INFO] [stdout]     |
[INFO] [stdout] 226 | fn iterator_map() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `iterator_sum` is never used
[INFO] [stdout]    --> src/main.rs:232:4
[INFO] [stdout]     |
[INFO] [stdout] 232 | fn iterator_sum() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `news_aggregate` is never used
[INFO] [stdout]    --> src/main.rs:269:4
[INFO] [stdout]     |
[INFO] [stdout] 269 | fn news_aggregate() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vector` is never used
[INFO] [stdout]    --> src/main.rs:305:4
[INFO] [stdout]     |
[INFO] [stdout] 305 | fn vector() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Counter` is never constructed
[INFO] [stdout]    --> src/main.rs:325:8
[INFO] [stdout]     |
[INFO] [stdout] 325 | struct Counter {
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]    --> src/main.rs:330:8
[INFO] [stdout]     |
[INFO] [stdout] 329 | impl Counter {
[INFO] [stdout]     | ------------ associated function in this implementation
[INFO] [stdout] 330 |     fn new() -> Counter {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `if_let` is never used
[INFO] [stdout]    --> src/main.rs:351:4
[INFO] [stdout]     |
[INFO] [stdout] 351 | fn if_let() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `value_in_cents` is never used
[INFO] [stdout]    --> src/main.rs:359:4
[INFO] [stdout]     |
[INFO] [stdout] 359 | fn value_in_cents(coin : Coin) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `option` is never used
[INFO] [stdout]    --> src/main.rs:371:4
[INFO] [stdout]     |
[INFO] [stdout] 371 | fn option() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `messages` is never used
[INFO] [stdout]    --> src/main.rs:378:4
[INFO] [stdout]     |
[INFO] [stdout] 378 | fn messages() {
[INFO] [stdout]     |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `rectangles` is never used
[INFO] [stdout]    --> src/main.rs:383:4
[INFO] [stdout]     |
[INFO] [stdout] 383 | fn rectangles() {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `build_user` is never used
[INFO] [stdout]    --> src/main.rs:395:4
[INFO] [stdout]     |
[INFO] [stdout] 395 | fn build_user(email: String, username: String) -> User {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `coins` is never used
[INFO] [stdout]    --> src/main.rs:404:4
[INFO] [stdout]     |
[INFO] [stdout] 404 | fn coins() {
[INFO] [stdout]     |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `slices` is never used
[INFO] [stdout]    --> src/main.rs:409:4
[INFO] [stdout]     |
[INFO] [stdout] 409 | fn slices() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `takes_ownership` is never used
[INFO] [stdout]    --> src/main.rs:419:4
[INFO] [stdout]     |
[INFO] [stdout] 419 | fn takes_ownership(some_string: String) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `makes_copy` is never used
[INFO] [stdout]    --> src/main.rs:423:4
[INFO] [stdout]     |
[INFO] [stdout] 423 | fn makes_copy(some_integer: i32) {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `first_word` is never used
[INFO] [stdout]    --> src/main.rs:427:4
[INFO] [stdout]     |
[INFO] [stdout] 427 | fn first_word(s: &String) -> usize {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `guess_number` is never used
[INFO] [stdout]    --> src/main.rs:440:4
[INFO] [stdout]     |
[INFO] [stdout] 440 | fn guess_number() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `summarize` is never used
[INFO] [stdout]  --> src/news_aggregator/mod.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 1 |     pub trait Summary {
[INFO] [stdout]   |               ------- method in this trait
[INFO] [stdout] 2 |         fn summarize(&self) -> String;
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `content` is never read
[INFO] [stdout]  --> src/news_aggregator/mod.rs:9:13
[INFO] [stdout]   |
[INFO] [stdout] 5 |     pub struct NewsArticle {
[INFO] [stdout]   |                ----------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 9 |         pub content: String
[INFO] [stdout]   |             ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `reply` and `retweet` are never read
[INFO] [stdout]   --> src/news_aggregator/mod.rs:21:13
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub struct Tweet {
[INFO] [stdout]    |                ----- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 21 |         pub reply: bool,
[INFO] [stdout]    |             ^^^^^
[INFO] [stdout] 22 |         pub retweet: bool
[INFO] [stdout]    |             ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:245:5
[INFO] [stdout]     |
[INFO] [stdout] 245 |     read_username_from_file();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 245 |     let _ = read_username_from_file();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.78s
[INFO] running `Command { std: "docker" "inspect" "d35c75d01d0a1df8489a5ffb8f464b9ddfda2c23f84d388138abc5585eaaf5a5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d35c75d01d0a1df8489a5ffb8f464b9ddfda2c23f84d388138abc5585eaaf5a5", kill_on_drop: false }`
[INFO] [stdout] d35c75d01d0a1df8489a5ffb8f464b9ddfda2c23f84d388138abc5585eaaf5a5
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid -Dtail-expr-drop-order" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7d0bf1958d84d371712c5923008c49c8632996a9dafb733cacd2598e9856bd74
[INFO] running `Command { std: "docker" "start" "-a" "7d0bf1958d84d371712c5923008c49c8632996a9dafb733cacd2598e9856bd74", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stderr]    Compiling rust_exploration v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `num`
[INFO] [stdout]    --> src/main.rs:177:45
[INFO] [stdout]     |
[INFO] [stdout] 177 |     let mut expensive_result = Cacher::new(|num| {
[INFO] [stdout]     |                                             ^^^ help: if this is intentional, prefix it with an underscore: `_num`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `equal_to_x`
[INFO] [stdout]    --> src/main.rs:212:9
[INFO] [stdout]     |
[INFO] [stdout] 212 |     let equal_to_x = |z : u32| z == x;
[INFO] [stdout]     |         ^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_equal_to_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `y`
[INFO] [stdout]    --> src/main.rs:213:9
[INFO] [stdout]     |
[INFO] [stdout] 213 |     let y = 4;
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_y`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `res`
[INFO] [stdout]    --> src/main.rs:229:9
[INFO] [stdout]     |
[INFO] [stdout] 229 |     let res: Vec<_> = v1.iter().map(|x| x + 1).collect();
[INFO] [stdout]     |         ^^^ help: if this is intentional, prefix it with an underscore: `_res`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `total`
[INFO] [stdout]    --> src/main.rs:236:9
[INFO] [stdout]     |
[INFO] [stdout] 236 |     let total: i32 = v1_iter.sum();
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_total`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `item`
[INFO] [stdout]    --> src/main.rs:289:9
[INFO] [stdout]     |
[INFO] [stdout] 289 |     let item = map.get(&key).unwrap();
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `s3`
[INFO] [stdout]    --> src/main.rs:296:9
[INFO] [stdout]     |
[INFO] [stdout] 296 |     let s3 = s1 + &s2;
[INFO] [stdout]     |         ^^ help: if this is intentional, prefix it with an underscore: `_s3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:306:9
[INFO] [stdout]     |
[INFO] [stdout] 306 |     let v: Vec<i32> = Vec::new();
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `third`
[INFO] [stdout]    --> src/main.rs:309:9
[INFO] [stdout]     |
[INFO] [stdout] 309 |     let third: &i32 = &v[2];
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_third`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_number`
[INFO] [stdout]    --> src/main.rs:372:9
[INFO] [stdout]     |
[INFO] [stdout] 372 |     let some_number = Some(5);
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `some_string`
[INFO] [stdout]    --> src/main.rs:373:9
[INFO] [stdout]     |
[INFO] [stdout] 373 |     let some_string = Some("A string");
[INFO] [stdout]     |         ^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_some_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `absent_number`
[INFO] [stdout]    --> src/main.rs:375:9
[INFO] [stdout]     |
[INFO] [stdout] 375 |     let absent_number : Option<i32> = None;
[INFO] [stdout]     |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_absent_number`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `rect3`
[INFO] [stdout]    --> src/main.rs:387:9
[INFO] [stdout]     |
[INFO] [stdout] 387 |     let rect3 = Rectangle {width: 60, height: 45};
[INFO] [stdout]     |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_rect3`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Pair` is never constructed
[INFO] [stdout]   --> src/main.rs:18:8
[INFO] [stdout]    |
[INFO] [stdout] 18 | struct Pair<T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> src/main.rs:24:8
[INFO] [stdout]    |
[INFO] [stdout] 23 | impl<T> Pair<T> {
[INFO] [stdout]    | --------------- associated function in this implementation
[INFO] [stdout] 24 |     fn new(x: T, y: T) -> Self {
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `cmp_display` is never used
[INFO] [stdout]   --> src/main.rs:33:8
[INFO] [stdout]    |
[INFO] [stdout] 32 | impl<T: Display + PartialOrd> Pair<T> {
[INFO] [stdout]    | ------------------------------------- method in this implementation
[INFO] [stdout] 33 |     fn cmp_display(&self) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `User` is never constructed
[INFO] [stdout]   --> src/main.rs:42:8
[INFO] [stdout]    |
[INFO] [stdout] 42 | struct User {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Rectangle` is never constructed
[INFO] [stdout]   --> src/main.rs:49:8
[INFO] [stdout]    |
[INFO] [stdout] 49 | struct Rectangle {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `area`, `can_hold`, and `square` are never used
[INFO] [stdout]   --> src/main.rs:55:8
[INFO] [stdout]    |
[INFO] [stdout] 54 | impl Rectangle {
[INFO] [stdout]    | -------------- associated items in this implementation
[INFO] [stdout] 55 |     fn area(&self) -> u32 {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] ...
[INFO] [stdout] 59 |     fn can_hold(&self, other: &Rectangle) -> bool {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 63 |     fn square(size: u32) -> Rectangle {
[INFO] [stdout]    |        ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `IpAddrKind` is never used
[INFO] [stdout]   --> src/main.rs:68:6
[INFO] [stdout]    |
[INFO] [stdout] 68 | enum IpAddrKind {
[INFO] [stdout]    |      ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `UsState` is never used
[INFO] [stdout]   --> src/main.rs:74:6
[INFO] [stdout]    |
[INFO] [stdout] 74 | enum UsState {
[INFO] [stdout]    |      ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Coin` is never used
[INFO] [stdout]   --> src/main.rs:80:6
[INFO] [stdout]    |
[INFO] [stdout] 80 | enum Coin {
[INFO] [stdout]    |      ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `Message` is never used
[INFO] [stdout]   --> src/main.rs:87:6
[INFO] [stdout]    |
[INFO] [stdout] 87 | enum Message {
[INFO] [stdout]    |      ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `call` is never used
[INFO] [stdout]   --> src/main.rs:95:8
[INFO] [stdout]    |
[INFO] [stdout] 94 | impl Message {
[INFO] [stdout]    | ------------ method in this implementation
[INFO] [stdout] 95 |     fn call(&self) {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `largest` is never used
[INFO] [stdout]    --> src/main.rs:100:5
[INFO] [stdout]     |
[INFO] [stdout] 100 |  fn largest<T : PartialOrd>(list: &[T]) -> &T {
[INFO] [stdout]     |     ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Point` is never constructed
[INFO] [stdout]    --> src/main.rs:112:8
[INFO] [stdout]     |
[INFO] [stdout] 112 | struct Point<T> {
[INFO] [stdout]     |        ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `simulated_expensive_calculation` is never used
[INFO] [stdout]    --> src/main.rs:204:4
[INFO] [stdout]     |
[INFO] [stdout] 204 | fn simulated_expensive_calculation(intensity: u32) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `closure_capturing_context` is never used
[INFO] [stdout]    --> src/main.rs:210:4
[INFO] [stdout]     |
[INFO] [stdout] 210 | fn closure_capturing_context() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `iterators` is never used
[INFO] [stdout]    --> src/main.rs:217:4
[INFO] [stdout]     |
[INFO] [stdout] 217 | fn iterators() {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `iterator_map` is never used
[INFO] [stdout]    --> src/main.rs:226:4
[INFO] [stdout]     |
[INFO] [stdout] 226 | fn iterator_map() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `iterator_sum` is never used
[INFO] [stdout]    --> src/main.rs:232:4
[INFO] [stdout]     |
[INFO] [stdout] 232 | fn iterator_sum() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `news_aggregate` is never used
[INFO] [stdout]    --> src/main.rs:269:4
[INFO] [stdout]     |
[INFO] [stdout] 269 | fn news_aggregate() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vector` is never used
[INFO] [stdout]    --> src/main.rs:305:4
[INFO] [stdout]     |
[INFO] [stdout] 305 | fn vector() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Counter` is never constructed
[INFO] [stdout]    --> src/main.rs:325:8
[INFO] [stdout]     |
[INFO] [stdout] 325 | struct Counter {
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]    --> src/main.rs:330:8
[INFO] [stdout]     |
[INFO] [stdout] 329 | impl Counter {
[INFO] [stdout]     | ------------ associated function in this implementation
[INFO] [stdout] 330 |     fn new() -> Counter {
[INFO] [stdout]     |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `if_let` is never used
[INFO] [stdout]    --> src/main.rs:351:4
[INFO] [stdout]     |
[INFO] [stdout] 351 | fn if_let() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `value_in_cents` is never used
[INFO] [stdout]    --> src/main.rs:359:4
[INFO] [stdout]     |
[INFO] [stdout] 359 | fn value_in_cents(coin : Coin) -> u32 {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `option` is never used
[INFO] [stdout]    --> src/main.rs:371:4
[INFO] [stdout]     |
[INFO] [stdout] 371 | fn option() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `messages` is never used
[INFO] [stdout]    --> src/main.rs:378:4
[INFO] [stdout]     |
[INFO] [stdout] 378 | fn messages() {
[INFO] [stdout]     |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `rectangles` is never used
[INFO] [stdout]    --> src/main.rs:383:4
[INFO] [stdout]     |
[INFO] [stdout] 383 | fn rectangles() {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `build_user` is never used
[INFO] [stdout]    --> src/main.rs:395:4
[INFO] [stdout]     |
[INFO] [stdout] 395 | fn build_user(email: String, username: String) -> User {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `coins` is never used
[INFO] [stdout]    --> src/main.rs:404:4
[INFO] [stdout]     |
[INFO] [stdout] 404 | fn coins() {
[INFO] [stdout]     |    ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `slices` is never used
[INFO] [stdout]    --> src/main.rs:409:4
[INFO] [stdout]     |
[INFO] [stdout] 409 | fn slices() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `takes_ownership` is never used
[INFO] [stdout]    --> src/main.rs:419:4
[INFO] [stdout]     |
[INFO] [stdout] 419 | fn takes_ownership(some_string: String) {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `makes_copy` is never used
[INFO] [stdout]    --> src/main.rs:423:4
[INFO] [stdout]     |
[INFO] [stdout] 423 | fn makes_copy(some_integer: i32) {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `first_word` is never used
[INFO] [stdout]    --> src/main.rs:427:4
[INFO] [stdout]     |
[INFO] [stdout] 427 | fn first_word(s: &String) -> usize {
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `guess_number` is never used
[INFO] [stdout]    --> src/main.rs:440:4
[INFO] [stdout]     |
[INFO] [stdout] 440 | fn guess_number() {
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: method `summarize` is never used
[INFO] [stdout]  --> src/news_aggregator/mod.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 1 |     pub trait Summary {
[INFO] [stdout]   |               ------- method in this trait
[INFO] [stdout] 2 |         fn summarize(&self) -> String;
[INFO] [stdout]   |            ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `content` is never read
[INFO] [stdout]  --> src/news_aggregator/mod.rs:9:13
[INFO] [stdout]   |
[INFO] [stdout] 5 |     pub struct NewsArticle {
[INFO] [stdout]   |                ----------- field in this struct
[INFO] [stdout] ...
[INFO] [stdout] 9 |         pub content: String
[INFO] [stdout]   |             ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `reply` and `retweet` are never read
[INFO] [stdout]   --> src/news_aggregator/mod.rs:21:13
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub struct Tweet {
[INFO] [stdout]    |                ----- fields in this struct
[INFO] [stdout] ...
[INFO] [stdout] 21 |         pub reply: bool,
[INFO] [stdout]    |             ^^^^^
[INFO] [stdout] 22 |         pub retweet: bool
[INFO] [stdout]    |             ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:245:5
[INFO] [stdout]     |
[INFO] [stdout] 245 |     read_username_from_file();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 245 |     let _ = read_username_from_file();
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.32s
[INFO] running `Command { std: "docker" "inspect" "7d0bf1958d84d371712c5923008c49c8632996a9dafb733cacd2598e9856bd74", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7d0bf1958d84d371712c5923008c49c8632996a9dafb733cacd2598e9856bd74", kill_on_drop: false }`
[INFO] [stdout] 7d0bf1958d84d371712c5923008c49c8632996a9dafb733cacd2598e9856bd74