[INFO] updating cached repository gdemarcsek/learn-rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/gdemarcsek/learn-rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/gdemarcsek/learn-rust" "work/ex/clippy-test-run/sources/stable/gh/gdemarcsek/learn-rust"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable/gh/gdemarcsek/learn-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/gdemarcsek/learn-rust" "work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/gdemarcsek/learn-rust"`
[INFO] [stderr] Cloning into 'work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/gdemarcsek/learn-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] c8caf07a1205b8638e5b0711fd943f663662d11d
[INFO] sha for GitHub repo gdemarcsek/learn-rust: c8caf07a1205b8638e5b0711fd943f663662d11d
[INFO] validating manifest of gdemarcsek/learn-rust on toolchain stable
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of gdemarcsek/learn-rust on toolchain stable+rustflags=-Dclippy::into_iter_on_array
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing gdemarcsek/learn-rust
[INFO] finished frobbing gdemarcsek/learn-rust
[INFO] frobbed toml for gdemarcsek/learn-rust written to work/ex/clippy-test-run/sources/stable/gh/gdemarcsek/learn-rust/Cargo.toml
[INFO] started frobbing gdemarcsek/learn-rust
[INFO] finished frobbing gdemarcsek/learn-rust
[INFO] frobbed toml for gdemarcsek/learn-rust written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/gh/gdemarcsek/learn-rust/Cargo.toml
[INFO] crate gdemarcsek/learn-rust has a lockfile. skipping
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] linting gdemarcsek/learn-rust against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-2/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/gh/gdemarcsek/learn-rust:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+stable" "clippy" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] b3fc153ed77f7ea85339aef01a2cad04225927e5387a27586eb342d2dfe974b1
[INFO] running `"docker" "start" "-a" "b3fc153ed77f7ea85339aef01a2cad04225927e5387a27586eb342d2dfe974b1"`
[INFO] [stderr]     Checking learn-rust v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/main.rs:81:5
[INFO] [stderr]    |
[INFO] [stderr] 81 |     return s;
[INFO] [stderr]    |     ^^^^^^^^^ help: remove `return` as shown: `s`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]    --> src/main.rs:232:30
[INFO] [stderr]     |
[INFO] [stderr] 232 |     let home = IpAddress::V4(2130706433);
[INFO] [stderr]     |                              ^^^^^^^^^^ help: consider: `2_130_706_433`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::unreadable_literal)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]    --> src/main.rs:233:33
[INFO] [stderr]     |
[INFO] [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
[INFO] [stderr]     |                                 ^^^^^^^^^ help: consider: `314_159_263`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]    --> src/main.rs:233:44
[INFO] [stderr]     |
[INFO] [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
[INFO] [stderr]     |                                            ^^^^^^ help: consider: `123_442`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::*`
[INFO] [stderr]    --> src/main.rs:297:9
[INFO] [stderr]     |
[INFO] [stderr] 297 |     use std::*;         // glob import from Rust's standard library
[INFO] [stderr]     |         ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unreachable pattern
[INFO] [stderr]    --> src/main.rs:269:9
[INFO] [stderr]     |
[INFO] [stderr] 269 |         _ => -1,    // _ is a placeholder that matches any value - if we put it as last, this will mean what the "default" label menas for "switch" in C++
[INFO] [stderr]     |         ^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unreachable_patterns)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let x = 42;             // (type is inferred by the compiler whenever possible)
[INFO] [stderr]    |         ^ help: consider using `_x` instead
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable `x` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:19:13
[INFO] [stderr]    |
[INFO] [stderr] 19 |     let mut x = 42;         // Now 'x' is declared to be mutable, thus...
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: consider using `_x` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `x` is never read
[INFO] [stderr]   --> src/main.rs:20:5
[INFO] [stderr]    |
[INFO] [stderr] 20 |     x = 21;                 // its value can be changed later on
[INFO] [stderr]    |     ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_assignments)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s`
[INFO] [stderr]   --> src/main.rs:40:13
[INFO] [stderr]    |
[INFO] [stderr] 40 |         let s = String::from("dynamically allocated string");           // s owns the allocated memory...
[INFO] [stderr]    |             ^ help: consider using `_s` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:50:9
[INFO] [stderr]    |
[INFO] [stderr] 50 |     let y = x;          // a copy of the value of 'x'
[INFO] [stderr]    |         ^ help: consider using `_y` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s4`
[INFO] [stderr]   --> src/main.rs:72:9
[INFO] [stderr]    |
[INFO] [stderr] 72 |     let s4 = gives_ownership();
[INFO] [stderr]    |         ^^ help: consider using `_s4` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r1`
[INFO] [stderr]    --> src/main.rs:105:13
[INFO] [stderr]     |
[INFO] [stderr] 105 |         let r1 = &mut s1;
[INFO] [stderr]     |             ^^ help: consider using `_r1` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r2`
[INFO] [stderr]    --> src/main.rs:110:9
[INFO] [stderr]     |
[INFO] [stderr] 110 |     let r2 = &s1;                   // but out of the scope of 'r1', we can create a reference again...
[INFO] [stderr]     |         ^^ help: consider using `_r2` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r3`
[INFO] [stderr]    --> src/main.rs:111:9
[INFO] [stderr]     |
[INFO] [stderr] 111 |     let r3 = &s1;                   // ...even multiple immutable ones
[INFO] [stderr]     |         ^^ help: consider using `_r3` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `slice3` is never read
[INFO] [stderr]    --> src/main.rs:150:13
[INFO] [stderr]     |
[INFO] [stderr] 150 |     let mut slice3 = &s[1..6];
[INFO] [stderr]     |             ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `slice4`
[INFO] [stderr]    --> src/main.rs:155:9
[INFO] [stderr]     |
[INFO] [stderr] 155 |     let slice4: &[i32];         // the type of each item must be 'i32'
[INFO] [stderr]     |         ^^^^^^ help: consider using `_slice4` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `red`
[INFO] [stderr]    --> src/main.rs:191:9
[INFO] [stderr]     |
[INFO] [stderr] 191 |     let red = RGBColor(0xff, 0x00, 0x00);
[INFO] [stderr]     |         ^^^ help: consider using `_red` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `foreign`
[INFO] [stderr]    --> src/main.rs:233:9
[INFO] [stderr]     |
[INFO] [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
[INFO] [stderr]     |         ^^^^^^^ help: consider using `_foreign` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `some_ip`
[INFO] [stderr]    --> src/main.rs:238:9
[INFO] [stderr]     |
[INFO] [stderr] 238 |     let some_ip = Some(home);
[INFO] [stderr]     |         ^^^^^^^ help: consider using `_some_ip` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `absent_ip`
[INFO] [stderr]    --> src/main.rs:240:9
[INFO] [stderr]     |
[INFO] [stderr] 240 |     let absent_ip: Option<IpAddress> = None; 
[INFO] [stderr]     |         ^^^^^^^^^ help: consider using `_absent_ip` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/main.rs:243:9
[INFO] [stderr]     |
[INFO] [stderr] 243 |     let x: i8 = 5;
[INFO] [stderr]     |         ^ help: consider using `_x` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]    --> src/main.rs:244:9
[INFO] [stderr]     |
[INFO] [stderr] 244 |     let y: Option<i8> = Some(5);
[INFO] [stderr]     |         ^ help: consider using `_y` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `retcode`
[INFO] [stderr]    --> src/main.rs:259:9
[INFO] [stderr]     |
[INFO] [stderr] 259 |     let retcode = match error {     // match forces us to cover all possible cases
[INFO] [stderr]     |         ^^^^^^^ help: consider using `_retcode` instead
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/main.rs:139:9
[INFO] [stderr]     |
[INFO] [stderr] 139 |     let mut s = String::from("hello world");
[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: variant is never constructed: `NetworkError`
[INFO] [stderr]    --> src/main.rs:252:9
[INFO] [stderr]     |
[INFO] [stderr] 252 |         NetworkError,
[INFO] [stderr]     |         ^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `SerilizationError`
[INFO] [stderr]    --> src/main.rs:253:9
[INFO] [stderr]     |
[INFO] [stderr] 253 |         SerilizationError(String),
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `closures`
[INFO] [stderr]    --> src/main.rs:310:1
[INFO] [stderr]     |
[INFO] [stderr] 310 | fn closures() {
[INFO] [stderr]     | ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: length comparison to zero
[INFO] [stderr]   --> src/main.rs:76:13
[INFO] [stderr]    |
[INFO] [stderr] 76 |     assert!(0 < s.len());
[INFO] [stderr]    |             ^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `!s.is_empty()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::len_zero)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/main.rs:120:20
[INFO] [stderr]     |
[INFO] [stderr] 120 | fn check_length(s: &String, l: usize) -> bool {
[INFO] [stderr]     |                    ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: variable `className` should have a snake case name such as `class_name`
[INFO] [stderr]    --> src/main.rs:264:41
[INFO] [stderr]     |
[INFO] [stderr] 264 |         RPCCallError::SerilizationError(className) => {
[INFO] [stderr]     |                                         ^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(non_snake_case)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/main.rs:81:5
[INFO] [stderr]    |
[INFO] [stderr] 81 |     return s;
[INFO] [stderr]    |     ^^^^^^^^^ help: remove `return` as shown: `s`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]    --> src/main.rs:232:30
[INFO] [stderr]     |
[INFO] [stderr] 232 |     let home = IpAddress::V4(2130706433);
[INFO] [stderr]     |                              ^^^^^^^^^^ help: consider: `2_130_706_433`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::unreadable_literal)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]    --> src/main.rs:233:33
[INFO] [stderr]     |
[INFO] [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
[INFO] [stderr]     |                                 ^^^^^^^^^ help: consider: `314_159_263`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal
[INFO] [stderr] 
[INFO] [stderr] warning: long literal lacking separators
[INFO] [stderr]    --> src/main.rs:233:44
[INFO] [stderr]     |
[INFO] [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
[INFO] [stderr]     |                                            ^^^^^^ help: consider: `123_442`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unreadable_literal
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::*`
[INFO] [stderr]    --> src/main.rs:297:9
[INFO] [stderr]     |
[INFO] [stderr] 297 |     use std::*;         // glob import from Rust's standard library
[INFO] [stderr]     |         ^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unreachable pattern
[INFO] [stderr]    --> src/main.rs:269:9
[INFO] [stderr]     |
[INFO] [stderr] 269 |         _ => -1,    // _ is a placeholder that matches any value - if we put it as last, this will mean what the "default" label menas for "switch" in C++
[INFO] [stderr]     |         ^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unreachable_patterns)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:17:9
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let x = 42;             // (type is inferred by the compiler whenever possible)
[INFO] [stderr]    |         ^ help: consider using `_x` instead
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variable `x` is assigned to, but never used
[INFO] [stderr]   --> src/main.rs:19:13
[INFO] [stderr]    |
[INFO] [stderr] 19 |     let mut x = 42;         // Now 'x' is declared to be mutable, thus...
[INFO] [stderr]    |             ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: consider using `_x` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `x` is never read
[INFO] [stderr]   --> src/main.rs:20:5
[INFO] [stderr]    |
[INFO] [stderr] 20 |     x = 21;                 // its value can be changed later on
[INFO] [stderr]    |     ^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(unused_assignments)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s`
[INFO] [stderr]   --> src/main.rs:40:13
[INFO] [stderr]    |
[INFO] [stderr] 40 |         let s = String::from("dynamically allocated string");           // s owns the allocated memory...
[INFO] [stderr]    |             ^ help: consider using `_s` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]   --> src/main.rs:50:9
[INFO] [stderr]    |
[INFO] [stderr] 50 |     let y = x;          // a copy of the value of 'x'
[INFO] [stderr]    |         ^ help: consider using `_y` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `s4`
[INFO] [stderr]   --> src/main.rs:72:9
[INFO] [stderr]    |
[INFO] [stderr] 72 |     let s4 = gives_ownership();
[INFO] [stderr]    |         ^^ help: consider using `_s4` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r1`
[INFO] [stderr]    --> src/main.rs:105:13
[INFO] [stderr]     |
[INFO] [stderr] 105 |         let r1 = &mut s1;
[INFO] [stderr]     |             ^^ help: consider using `_r1` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r2`
[INFO] [stderr]    --> src/main.rs:110:9
[INFO] [stderr]     |
[INFO] [stderr] 110 |     let r2 = &s1;                   // but out of the scope of 'r1', we can create a reference again...
[INFO] [stderr]     |         ^^ help: consider using `_r2` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `r3`
[INFO] [stderr]    --> src/main.rs:111:9
[INFO] [stderr]     |
[INFO] [stderr] 111 |     let r3 = &s1;                   // ...even multiple immutable ones
[INFO] [stderr]     |         ^^ help: consider using `_r3` instead
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `slice3` is never read
[INFO] [stderr]    --> src/main.rs:150:13
[INFO] [stderr]     |
[INFO] [stderr] 150 |     let mut slice3 = &s[1..6];
[INFO] [stderr]     |             ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `slice4`
[INFO] [stderr]    --> src/main.rs:155:9
[INFO] [stderr]     |
[INFO] [stderr] 155 |     let slice4: &[i32];         // the type of each item must be 'i32'
[INFO] [stderr]     |         ^^^^^^ help: consider using `_slice4` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `red`
[INFO] [stderr]    --> src/main.rs:191:9
[INFO] [stderr]     |
[INFO] [stderr] 191 |     let red = RGBColor(0xff, 0x00, 0x00);
[INFO] [stderr]     |         ^^^ help: consider using `_red` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `foreign`
[INFO] [stderr]    --> src/main.rs:233:9
[INFO] [stderr]     |
[INFO] [stderr] 233 |     let foreign = IpAddress::V6(314159263, 123442);
[INFO] [stderr]     |         ^^^^^^^ help: consider using `_foreign` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `some_ip`
[INFO] [stderr]    --> src/main.rs:238:9
[INFO] [stderr]     |
[INFO] [stderr] 238 |     let some_ip = Some(home);
[INFO] [stderr]     |         ^^^^^^^ help: consider using `_some_ip` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `absent_ip`
[INFO] [stderr]    --> src/main.rs:240:9
[INFO] [stderr]     |
[INFO] [stderr] 240 |     let absent_ip: Option<IpAddress> = None; 
[INFO] [stderr]     |         ^^^^^^^^^ help: consider using `_absent_ip` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]    --> src/main.rs:243:9
[INFO] [stderr]     |
[INFO] [stderr] 243 |     let x: i8 = 5;
[INFO] [stderr]     |         ^ help: consider using `_x` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `y`
[INFO] [stderr]    --> src/main.rs:244:9
[INFO] [stderr]     |
[INFO] [stderr] 244 |     let y: Option<i8> = Some(5);
[INFO] [stderr]     |         ^ help: consider using `_y` instead
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `retcode`
[INFO] [stderr]    --> src/main.rs:259:9
[INFO] [stderr]     |
[INFO] [stderr] 259 |     let retcode = match error {     // match forces us to cover all possible cases
[INFO] [stderr]     |         ^^^^^^^ help: consider using `_retcode` instead
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]    --> src/main.rs:139:9
[INFO] [stderr]     |
[INFO] [stderr] 139 |     let mut s = String::from("hello world");
[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: variant is never constructed: `NetworkError`
[INFO] [stderr]    --> src/main.rs:252:9
[INFO] [stderr]     |
[INFO] [stderr] 252 |         NetworkError,
[INFO] [stderr]     |         ^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(dead_code)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `SerilizationError`
[INFO] [stderr]    --> src/main.rs:253:9
[INFO] [stderr]     |
[INFO] [stderr] 253 |         SerilizationError(String),
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: function is never used: `closures`
[INFO] [stderr]    --> src/main.rs:310:1
[INFO] [stderr]     |
[INFO] [stderr] 310 | fn closures() {
[INFO] [stderr]     | ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: length comparison to zero
[INFO] [stderr]   --> src/main.rs:76:13
[INFO] [stderr]    |
[INFO] [stderr] 76 |     assert!(0 < s.len());
[INFO] [stderr]    |             ^^^^^^^^^^^ help: using `is_empty` is clearer and more explicit: `!s.is_empty()`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::len_zero)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#len_zero
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/main.rs:120:20
[INFO] [stderr]     |
[INFO] [stderr] 120 | fn check_length(s: &String, l: usize) -> bool {
[INFO] [stderr]     |                    ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: variable `className` should have a snake case name such as `class_name`
[INFO] [stderr]    --> src/main.rs:264:41
[INFO] [stderr]     |
[INFO] [stderr] 264 |         RPCCallError::SerilizationError(className) => {
[INFO] [stderr]     |                                         ^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(non_snake_case)] on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.06s
[INFO] running `"docker" "inspect" "b3fc153ed77f7ea85339aef01a2cad04225927e5387a27586eb342d2dfe974b1"`
[INFO] running `"docker" "rm" "-f" "b3fc153ed77f7ea85339aef01a2cad04225927e5387a27586eb342d2dfe974b1"`
[INFO] [stdout] b3fc153ed77f7ea85339aef01a2cad04225927e5387a27586eb342d2dfe974b1