[INFO] cloning repository https://github.com/FeistyKit/simplecards
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/FeistyKit/simplecards" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFeistyKit%2Fsimplecards", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFeistyKit%2Fsimplecards'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ac17bb9aeb947b89832c3f716c4316f789983b44
[INFO] checking FeistyKit/simplecards against master#4eb62535fc12dd1a63fd43a4173e224e79313c4d for pr-158816
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FFeistyKit%2Fsimplecards" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/FeistyKit/simplecards
[INFO] finished tweaking git repo https://github.com/FeistyKit/simplecards
[INFO] tweaked toml for git repo https://github.com/FeistyKit/simplecards written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/FeistyKit/simplecards on toolchain 4eb62535fc12dd1a63fd43a4173e224e79313c4d
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4eb62535fc12dd1a63fd43a4173e224e79313c4d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/FeistyKit/simplecards 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" "+4eb62535fc12dd1a63fd43a4173e224e79313c4d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded proc-macro2 v1.0.30
[INFO] [stderr]   Downloaded signal-hook v0.3.10
[INFO] [stderr]   Downloaded serde_yaml v0.8.21
[INFO] [stderr]   Downloaded tui v0.16.0
[INFO] [stderr]   Downloaded libc v0.2.104
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:3d5ced03c013a94a2f102a4510f48a6e9184255caf5fd8244f58017bde7f5210" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] 10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9
[INFO] running `Command { std: "docker" "start" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9" "/opt/rustwide/cargo-home/bin/cargo" "+4eb62535fc12dd1a63fd43a4173e224e79313c4d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-w" "/opt/rustwide/workdir" "--user" "0:0" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9" "/opt/rustwide/cargo-home/bin/cargo" "+4eb62535fc12dd1a63fd43a4173e224e79313c4d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.104
[INFO] [stderr]    Compiling proc-macro2 v1.0.30
[INFO] [stderr]    Compiling syn v1.0.80
[INFO] [stderr]    Compiling signal-hook v0.3.10
[INFO] [stderr]    Compiling parking_lot_core v0.8.5
[INFO] [stderr]    Compiling serde_derive v1.0.130
[INFO] [stderr]     Checking smallvec v1.7.0
[INFO] [stderr]    Compiling serde v1.0.130
[INFO] [stderr]     Checking instant v0.1.12
[INFO] [stderr]     Checking lock_api v0.4.5
[INFO] [stderr]    Compiling indexmap v1.7.0
[INFO] [stderr]     Checking linked-hash-map v0.5.4
[INFO] [stderr]    Compiling serde_json v1.0.68
[INFO] [stderr]     Checking dtoa v0.4.8
[INFO] [stderr]     Checking unicode-segmentation v1.8.0
[INFO] [stderr]     Checking itoa v0.4.8
[INFO] [stderr]     Checking cassowary v0.3.0
[INFO] [stderr]     Checking yaml-rust v0.4.5
[INFO] [stderr]    Compiling quote v1.0.10
[INFO] [stderr]     Checking signal-hook-registry v1.4.0
[INFO] [stderr]     Checking mio v0.7.14
[INFO] [stderr]     Checking dirs-sys v0.3.6
[INFO] [stderr]     Checking directories v4.0.1
[INFO] [stderr]     Checking parking_lot v0.11.2
[INFO] [stderr]     Checking signal-hook-mio v0.2.1
[INFO] [stderr]     Checking crossterm v0.20.0
[INFO] [stderr]     Checking tui v0.16.0
[INFO] [stderr]     Checking serde_yaml v0.8.21
[INFO] [stderr]     Checking simplecards v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]   --> src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 21 | /     loop {
[INFO] [stdout] 22 | |         term.draw(termdraw)?;
[INFO] [stdout] 23 | |     }
[INFO] [stdout]    | |_____- any code following this expression is unreachable
[INFO] [stdout] 24 |       Ok(())
[INFO] [stdout]    |       ^^^^^^ unreachable expression
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unreachable expression
[INFO] [stdout]   --> src/main.rs:24:5
[INFO] [stdout]    |
[INFO] [stdout] 21 | /     loop {
[INFO] [stdout] 22 | |         term.draw(termdraw)?;
[INFO] [stdout] 23 | |     }
[INFO] [stdout]    | |_____- any code following this expression is unreachable
[INFO] [stdout] 24 |       Ok(())
[INFO] [stdout]    |       ^^^^^^ unreachable expression
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unreachable_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_event` is never used
[INFO] [stdout]   --> src/main.rs:52:4
[INFO] [stdout]    |
[INFO] [stdout] 52 | fn get_event() -> AnyResult<Option<event::Event>> {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `TabState` is never constructed
[INFO] [stdout]   --> src/main.rs:59:8
[INFO] [stdout]    |
[INFO] [stdout] 59 | struct TabState<'a> {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `data_dir` is never used
[INFO] [stdout]   --> src/storage.rs:10:4
[INFO] [stdout]    |
[INFO] [stdout] 10 | fn data_dir() -> AnyResult<std::path::PathBuf> {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `config_dir` is never used
[INFO] [stdout]   --> src/storage.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn config_dir() -> AnyResult<std::path::PathBuf> {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `construct_set` is never used
[INFO] [stdout]   --> src/storage.rs:28:8
[INFO] [stdout]    |
[INFO] [stdout] 28 | pub fn construct_set(
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_item_list` is never used
[INFO] [stdout]   --> src/storage.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn make_item_list(source_files: Vec<String>) -> AnyResult<Vec<VocabEntry>> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_config` is never used
[INFO] [stdout]   --> src/storage.rs:60:4
[INFO] [stdout]    |
[INFO] [stdout] 60 | fn make_config(config_file: Option<String>, config_default: bool) -> VocabRules {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `try_make_config` is never used
[INFO] [stdout]   --> src/storage.rs:68:4
[INFO] [stdout]    |
[INFO] [stdout] 68 | fn try_make_config(config_file: Option<String>) -> AnyResult<VocabRules> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `save_set` is never used
[INFO] [stdout]   --> src/storage.rs:88:8
[INFO] [stdout]    |
[INFO] [stdout] 88 | pub fn save_set(
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `save_config` is never used
[INFO] [stdout]    --> src/storage.rs:100:4
[INFO] [stdout]     |
[INFO] [stdout] 100 | fn save_config(config: &VocabRules) -> AnyResult<()> {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `save_data` is never used
[INFO] [stdout]    --> src/storage.rs:114:4
[INFO] [stdout]     |
[INFO] [stdout] 114 | fn save_data(data: std::collections::HashMap<&str, Vec<&VocabEntry>>) -> AnyResult<()> {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `VocabEntry` is never constructed
[INFO] [stdout]  --> src/vocab.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub struct VocabEntry {
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `increment` and `user_new` are never used
[INFO] [stdout]   --> src/vocab.rs:19:12
[INFO] [stdout]    |
[INFO] [stdout] 17 | impl VocabEntry {
[INFO] [stdout]    | --------------- associated items in this implementation
[INFO] [stdout] 18 |     // Will be called when the user tries a vocab card
[INFO] [stdout] 19 |     pub fn increment(&mut self, correct: bool, instant_change: bool) {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 33 |     pub fn user_new(key: String, val: String, path: String) -> VocabEntry {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `VocabState` is never used
[INFO] [stdout]   --> src/vocab.rs:49:10
[INFO] [stdout]    |
[INFO] [stdout] 49 | pub enum VocabState {
[INFO] [stdout]    |          ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `VocabSet` is never constructed
[INFO] [stdout]   --> src/vocab.rs:57:12
[INFO] [stdout]    |
[INFO] [stdout] 57 | pub struct VocabSet {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `VocabRules` is never constructed
[INFO] [stdout]   --> src/vocab.rs:66:12
[INFO] [stdout]    |
[INFO] [stdout] 66 | pub struct VocabRules {
[INFO] [stdout]    |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `from_unsorted` and `to_saveable` are never used
[INFO] [stdout]    --> src/vocab.rs:92:12
[INFO] [stdout]     |
[INFO] [stdout]  90 | impl VocabSet {
[INFO] [stdout]     | ------------- associated items in this implementation
[INFO] [stdout]  91 |     // construct the set from unparsed items
[INFO] [stdout]  92 |     pub fn from_unsorted(items: Vec<VocabEntry>, rules: VocabRules) -> VocabSet {
[INFO] [stdout]     |            ^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 120 |     pub fn to_saveable<'a>(
[INFO] [stdout]     |            ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/storage.rs:125:9
[INFO] [stdout]     |
[INFO] [stdout] 125 |         f.write(string.as_bytes());
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 125 |         let _ = f.write(string.as_bytes());
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `get_event` is never used
[INFO] [stdout]   --> src/main.rs:52:4
[INFO] [stdout]    |
[INFO] [stdout] 52 | fn get_event() -> AnyResult<Option<event::Event>> {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `TabState` is never constructed
[INFO] [stdout]   --> src/main.rs:59:8
[INFO] [stdout]    |
[INFO] [stdout] 59 | struct TabState<'a> {
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `data_dir` is never used
[INFO] [stdout]   --> src/storage.rs:10:4
[INFO] [stdout]    |
[INFO] [stdout] 10 | fn data_dir() -> AnyResult<std::path::PathBuf> {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `config_dir` is never used
[INFO] [stdout]   --> src/storage.rs:18:4
[INFO] [stdout]    |
[INFO] [stdout] 18 | fn config_dir() -> AnyResult<std::path::PathBuf> {
[INFO] [stdout]    |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `construct_set` is never used
[INFO] [stdout]   --> src/storage.rs:28:8
[INFO] [stdout]    |
[INFO] [stdout] 28 | pub fn construct_set(
[INFO] [stdout]    |        ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_item_list` is never used
[INFO] [stdout]   --> src/storage.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn make_item_list(source_files: Vec<String>) -> AnyResult<Vec<VocabEntry>> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `make_config` is never used
[INFO] [stdout]   --> src/storage.rs:60:4
[INFO] [stdout]    |
[INFO] [stdout] 60 | fn make_config(config_file: Option<String>, config_default: bool) -> VocabRules {
[INFO] [stdout]    |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `try_make_config` is never used
[INFO] [stdout]   --> src/storage.rs:68:4
[INFO] [stdout]    |
[INFO] [stdout] 68 | fn try_make_config(config_file: Option<String>) -> AnyResult<VocabRules> {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `save_set` is never used
[INFO] [stdout]   --> src/storage.rs:88:8
[INFO] [stdout]    |
[INFO] [stdout] 88 | pub fn save_set(
[INFO] [stdout]    |        ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `save_config` is never used
[INFO] [stdout]    --> src/storage.rs:100:4
[INFO] [stdout]     |
[INFO] [stdout] 100 | fn save_config(config: &VocabRules) -> AnyResult<()> {
[INFO] [stdout]     |    ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `save_data` is never used
[INFO] [stdout]    --> src/storage.rs:114:4
[INFO] [stdout]     |
[INFO] [stdout] 114 | fn save_data(data: std::collections::HashMap<&str, Vec<&VocabEntry>>) -> AnyResult<()> {
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `VocabEntry` is never constructed
[INFO] [stdout]  --> src/vocab.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 | pub struct VocabEntry {
[INFO] [stdout]   |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `increment` and `user_new` are never used
[INFO] [stdout]   --> src/vocab.rs:19:12
[INFO] [stdout]    |
[INFO] [stdout] 17 | impl VocabEntry {
[INFO] [stdout]    | --------------- associated items in this implementation
[INFO] [stdout] 18 |     // Will be called when the user tries a vocab card
[INFO] [stdout] 19 |     pub fn increment(&mut self, correct: bool, instant_change: bool) {
[INFO] [stdout]    |            ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 33 |     pub fn user_new(key: String, val: String, path: String) -> VocabEntry {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `VocabState` is never used
[INFO] [stdout]   --> src/vocab.rs:49:10
[INFO] [stdout]    |
[INFO] [stdout] 49 | pub enum VocabState {
[INFO] [stdout]    |          ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `VocabSet` is never constructed
[INFO] [stdout]   --> src/vocab.rs:57:12
[INFO] [stdout]    |
[INFO] [stdout] 57 | pub struct VocabSet {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `VocabRules` is never constructed
[INFO] [stdout]   --> src/vocab.rs:66:12
[INFO] [stdout]    |
[INFO] [stdout] 66 | pub struct VocabRules {
[INFO] [stdout]    |            ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `from_unsorted` and `to_saveable` are never used
[INFO] [stdout]    --> src/vocab.rs:92:12
[INFO] [stdout]     |
[INFO] [stdout]  90 | impl VocabSet {
[INFO] [stdout]     | ------------- associated items in this implementation
[INFO] [stdout]  91 |     // construct the set from unparsed items
[INFO] [stdout]  92 |     pub fn from_unsorted(items: Vec<VocabEntry>, rules: VocabRules) -> VocabSet {
[INFO] [stdout]     |            ^^^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 120 |     pub fn to_saveable<'a>(
[INFO] [stdout]     |            ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/storage.rs:125:9
[INFO] [stdout]     |
[INFO] [stdout] 125 |         f.write(string.as_bytes());
[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)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 125 |         let _ = f.write(string.as_bytes());
[INFO] [stdout]     |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 12.17s
[INFO] running `Command { std: "docker" "inspect" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9", kill_on_drop: false }`
[INFO] [stdout] 10a9b2b9ef0bd4486c161e5db316d27005c2abc5a6277cb5bec40323467c16a9
