[INFO] cloning repository https://github.com/jangozw/rust-study
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jangozw/rust-study" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjangozw%2Frust-study", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjangozw%2Frust-study'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6d4ff38159d2a37d49a1e7fa8d71f4099fd84337
[INFO] testing jangozw/rust-study against nightly-2025-01-18+rustflags=-Zrandomize-layout for randomize-layout-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjangozw%2Frust-study" "/workspace/builds/worker-3-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jangozw/rust-study on toolchain nightly-2025-01-18
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+nightly-2025-01-18" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/jangozw/rust-study
[INFO] finished tweaking git repo https://github.com/jangozw/rust-study
[INFO] tweaked toml for git repo https://github.com/jangozw/rust-study written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/jangozw/rust-study 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" "+nightly-2025-01-18" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2025-01-18" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 3ad439566676be74e0dcf65954f01bbe822e41fc1cde5287789c187e218ee774
[INFO] running `Command { std: "docker" "start" "-a" "3ad439566676be74e0dcf65954f01bbe822e41fc1cde5287789c187e218ee774", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3ad439566676be74e0dcf65954f01bbe822e41fc1cde5287789c187e218ee774", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3ad439566676be74e0dcf65954f01bbe822e41fc1cde5287789c187e218ee774", kill_on_drop: false }`
[INFO] [stdout] 3ad439566676be74e0dcf65954f01bbe822e41fc1cde5287789c187e218ee774
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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 -Zrandomize-layout" "-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2025-01-18" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] afb8659406956e3bc138e907fe80240b7736e2b30c4c55f042668f56528aa27b
[INFO] running `Command { std: "docker" "start" "-a" "afb8659406956e3bc138e907fe80240b7736e2b30c4c55f042668f56528aa27b", kill_on_drop: false }`
[INFO] [stderr]    Compiling datastruct v0.1.0 (/opt/rustwide/workdir/datastruct)
[INFO] [stdout] warning: unused imports: `Display` and `Error`
[INFO] [stdout]  --> datastruct/src/single_link.rs:1:23
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fmt::{Debug, Display, Error};
[INFO] [stdout]   |                       ^^^^^^^  ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `link_node` should have an upper camel case name
[INFO] [stdout]   --> datastruct/src/single_link.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct link_node<T> {
[INFO] [stdout]    |        ^^^^^^^^^ help: convert the identifier to upper camel case: `LinkNode`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `link_list` should have an upper camel case name
[INFO] [stdout]   --> datastruct/src/single_link.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | struct link_list<T>{
[INFO] [stdout]    |        ^^^^^^^^^ help: convert the identifier to upper camel case: `LinkList`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> datastruct/src/single_link.rs:83:13
[INFO] [stdout]    |
[INFO] [stdout] 83 |         for i in 0..pos{
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> datastruct/src/single_link.rs:76:13
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let mut insert = Box::new(link_node::new(data));
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `link_node` is never constructed
[INFO] [stdout]   --> datastruct/src/single_link.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct link_node<T> {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `link_list` is never constructed
[INFO] [stdout]   --> datastruct/src/single_link.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | struct link_list<T>{
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> datastruct/src/single_link.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | impl<T> link_node<T> {
[INFO] [stdout]    | -------------------- associated function in this implementation
[INFO] [stdout] 22 |     // 新建节点
[INFO] [stdout] 23 |     fn new(data: T)->Self{
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `head_insert`, `rear_insert`, and `position_insert` are never used
[INFO] [stdout]   --> datastruct/src/single_link.rs:31:8
[INFO] [stdout]    |
[INFO] [stdout] 29 | impl<T> link_list<T> {
[INFO] [stdout]    | -------------------- associated items in this implementation
[INFO] [stdout] 30 |     // 新建一个链表
[INFO] [stdout] 31 |     fn new()->Self{
[INFO] [stdout]    |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 37 |     fn head_insert(&mut self, data: T) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 50 |     fn rear_insert(&mut self, data: T){
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 74 |     fn position_insert(&mut self, data: T, pos: i32) ->Result<i32, String> {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rust-study v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.34s
[INFO] running `Command { std: "docker" "inspect" "afb8659406956e3bc138e907fe80240b7736e2b30c4c55f042668f56528aa27b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "afb8659406956e3bc138e907fe80240b7736e2b30c4c55f042668f56528aa27b", kill_on_drop: false }`
[INFO] [stdout] afb8659406956e3bc138e907fe80240b7736e2b30c4c55f042668f56528aa27b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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 -Zrandomize-layout" "-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2025-01-18" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c51bc33cc6e47f590f10898b7fd70ba109e568bf4a59d82b73be4bbc7cbb2459
[INFO] running `Command { std: "docker" "start" "-a" "c51bc33cc6e47f590f10898b7fd70ba109e568bf4a59d82b73be4bbc7cbb2459", kill_on_drop: false }`
[INFO] [stdout] warning: unused imports: `Display` and `Error`
[INFO] [stdout]  --> datastruct/src/single_link.rs:1:23
[INFO] [stdout]   |
[INFO] [stdout] 1 | use std::fmt::{Debug, Display, Error};
[INFO] [stdout]   |                       ^^^^^^^  ^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `link_node` should have an upper camel case name
[INFO] [stdout]   --> datastruct/src/single_link.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct link_node<T> {
[INFO] [stdout]    |        ^^^^^^^^^ help: convert the identifier to upper camel case: `LinkNode`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `link_list` should have an upper camel case name
[INFO] [stdout]   --> datastruct/src/single_link.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | struct link_list<T>{
[INFO] [stdout]    |        ^^^^^^^^^ help: convert the identifier to upper camel case: `LinkList`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> datastruct/src/single_link.rs:83:13
[INFO] [stdout]    |
[INFO] [stdout] 83 |         for i in 0..pos{
[INFO] [stdout]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> datastruct/src/single_link.rs:76:13
[INFO] [stdout]    |
[INFO] [stdout] 76 |         let mut insert = Box::new(link_node::new(data));
[INFO] [stdout]    |             ----^^^^^^
[INFO] [stdout]    |             |
[INFO] [stdout]    |             help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `link_node` is never constructed
[INFO] [stdout]   --> datastruct/src/single_link.rs:10:8
[INFO] [stdout]    |
[INFO] [stdout] 10 | struct link_node<T> {
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `link_list` is never constructed
[INFO] [stdout]   --> datastruct/src/single_link.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | struct link_list<T>{
[INFO] [stdout]    |        ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `new` is never used
[INFO] [stdout]   --> datastruct/src/single_link.rs:23:8
[INFO] [stdout]    |
[INFO] [stdout] 21 | impl<T> link_node<T> {
[INFO] [stdout]    | -------------------- associated function in this implementation
[INFO] [stdout] 22 |     // 新建节点
[INFO] [stdout] 23 |     fn new(data: T)->Self{
[INFO] [stdout]    |        ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated items `new`, `head_insert`, `rear_insert`, and `position_insert` are never used
[INFO] [stdout]   --> datastruct/src/single_link.rs:31:8
[INFO] [stdout]    |
[INFO] [stdout] 29 | impl<T> link_list<T> {
[INFO] [stdout]    | -------------------- associated items in this implementation
[INFO] [stdout] 30 |     // 新建一个链表
[INFO] [stdout] 31 |     fn new()->Self{
[INFO] [stdout]    |        ^^^
[INFO] [stdout] ...
[INFO] [stdout] 37 |     fn head_insert(&mut self, data: T) {
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 50 |     fn rear_insert(&mut self, data: T){
[INFO] [stdout]    |        ^^^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 74 |     fn position_insert(&mut self, data: T, pos: i32) ->Result<i32, String> {
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rust-study v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.23s
[INFO] running `Command { std: "docker" "inspect" "c51bc33cc6e47f590f10898b7fd70ba109e568bf4a59d82b73be4bbc7cbb2459", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c51bc33cc6e47f590f10898b7fd70ba109e568bf4a59d82b73be4bbc7cbb2459", kill_on_drop: false }`
[INFO] [stdout] c51bc33cc6e47f590f10898b7fd70ba109e568bf4a59d82b73be4bbc7cbb2459
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/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 -Zrandomize-layout" "-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+nightly-2025-01-18" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 6d596fc9a4319dc0fb547306abcd1cdf18b08f4629a3949d654a0ab5365f97a6
[INFO] running `Command { std: "docker" "start" "-a" "6d596fc9a4319dc0fb547306abcd1cdf18b08f4629a3949d654a0ab5365f97a6", kill_on_drop: false }`
[INFO] [stderr] warning: unused imports: `Display` and `Error`
[INFO] [stderr]  --> datastruct/src/single_link.rs:1:23
[INFO] [stderr]   |
[INFO] [stderr] 1 | use std::fmt::{Debug, Display, Error};
[INFO] [stderr]   |                       ^^^^^^^  ^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: type `link_node` should have an upper camel case name
[INFO] [stderr]   --> datastruct/src/single_link.rs:10:8
[INFO] [stderr]    |
[INFO] [stderr] 10 | struct link_node<T> {
[INFO] [stderr]    |        ^^^^^^^^^ help: convert the identifier to upper camel case: `LinkNode`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: type `link_list` should have an upper camel case name
[INFO] [stderr]   --> datastruct/src/single_link.rs:17:8
[INFO] [stderr]    |
[INFO] [stderr] 17 | struct link_list<T>{
[INFO] [stderr]    |        ^^^^^^^^^ help: convert the identifier to upper camel case: `LinkList`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stderr]   --> datastruct/src/single_link.rs:83:13
[INFO] [stderr]    |
[INFO] [stderr] 83 |         for i in 0..pos{
[INFO] [stderr]    |             ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> datastruct/src/single_link.rs:76:13
[INFO] [stderr]    |
[INFO] [stderr] 76 |         let mut insert = Box::new(link_node::new(data));
[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: struct `link_node` is never constructed
[INFO] [stderr]   --> datastruct/src/single_link.rs:10:8
[INFO] [stderr]    |
[INFO] [stderr] 10 | struct link_node<T> {
[INFO] [stderr]    |        ^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: struct `link_list` is never constructed
[INFO] [stderr]   --> datastruct/src/single_link.rs:17:8
[INFO] [stderr]    |
[INFO] [stderr] 17 | struct link_list<T>{
[INFO] [stderr]    |        ^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated function `new` is never used
[INFO] [stderr]   --> datastruct/src/single_link.rs:23:8
[INFO] [stderr]    |
[INFO] [stderr] 21 | impl<T> link_node<T> {
[INFO] [stderr]    | -------------------- associated function in this implementation
[INFO] [stderr] 22 |     // 新建节点
[INFO] [stderr] 23 |     fn new(data: T)->Self{
[INFO] [stderr]    |        ^^^
[INFO] [stderr] 
[INFO] [stderr] warning: associated items `new`, `head_insert`, `rear_insert`, and `position_insert` are never used
[INFO] [stderr]   --> datastruct/src/single_link.rs:31:8
[INFO] [stderr]    |
[INFO] [stderr] 29 | impl<T> link_list<T> {
[INFO] [stderr]    | -------------------- associated items in this implementation
[INFO] [stderr] 30 |     // 新建一个链表
[INFO] [stderr] 31 |     fn new()->Self{
[INFO] [stderr]    |        ^^^
[INFO] [stderr] ...
[INFO] [stderr] 37 |     fn head_insert(&mut self, data: T) {
[INFO] [stderr]    |        ^^^^^^^^^^^
[INFO] [stderr] ...
[INFO] [stderr] 50 |     fn rear_insert(&mut self, data: T){
[INFO] [stderr]    |        ^^^^^^^^^^^
[INFO] [stderr] ...
[INFO] [stderr] 74 |     fn position_insert(&mut self, data: T, pos: i32) ->Result<i32, String> {
[INFO] [stderr]    |        ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: `datastruct` (lib) generated 9 warnings (run `cargo fix --lib -p datastruct` to apply 2 suggestions)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/rust_study-80cc27e289d8eeee)
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "6d596fc9a4319dc0fb547306abcd1cdf18b08f4629a3949d654a0ab5365f97a6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6d596fc9a4319dc0fb547306abcd1cdf18b08f4629a3949d654a0ab5365f97a6", kill_on_drop: false }`
[INFO] [stdout] 6d596fc9a4319dc0fb547306abcd1cdf18b08f4629a3949d654a0ab5365f97a6
