[INFO] cloning repository https://github.com/4nemo/kitlit_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/4nemo/kitlit_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F4nemo%2Fkitlit_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F4nemo%2Fkitlit_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 99bc7c2409ace2aae3d7a189a73910aa0831543f
[INFO] checking 4nemo/kitlit_rust against master#b3f8586fb1e4859678d6b231e780ff81801d2282 for pr-147589
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F4nemo%2Fkitlit_rust" "/workspace/builds/worker-2-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/4nemo/kitlit_rust
[INFO] finished tweaking git repo https://github.com/4nemo/kitlit_rust
[INFO] tweaked toml for git repo https://github.com/4nemo/kitlit_rust written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/4nemo/kitlit_rust on toolchain b3f8586fb1e4859678d6b231e780ff81801d2282
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b3f8586fb1e4859678d6b231e780ff81801d2282" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/4nemo/kitlit_rust 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" "+b3f8586fb1e4859678d6b231e780ff81801d2282" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded syn v2.0.104
[INFO] [stderr]   Downloaded libc v0.2.174
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b3f8586fb1e4859678d6b231e780ff81801d2282" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
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[INFO] running `Command { std: "docker" "start" "-a" "c535312b3c4726b42d0a3df02d71a99b80c38366289d7a56f2b831a3701e94ac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c535312b3c4726b42d0a3df02d71a99b80c38366289d7a56f2b831a3701e94ac", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c535312b3c4726b42d0a3df02d71a99b80c38366289d7a56f2b831a3701e94ac", kill_on_drop: false }`
[INFO] [stdout] c535312b3c4726b42d0a3df02d71a99b80c38366289d7a56f2b831a3701e94ac
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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" "-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b3f8586fb1e4859678d6b231e780ff81801d2282" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f696538bb48c626752536154737a89f5d5ac92283da6b9a536deae38ff34fbf8
[INFO] running `Command { std: "docker" "start" "-a" "f696538bb48c626752536154737a89f5d5ac92283da6b9a536deae38ff34fbf8", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.174
[INFO] [stderr]    Compiling zerocopy v0.8.26
[INFO] [stderr]    Compiling getrandom v0.3.3
[INFO] [stderr]     Checking cfg-if v1.0.1
[INFO] [stderr]     Checking rand_core v0.9.3
[INFO] [stderr]     Checking ppv-lite86 v0.2.21
[INFO] [stderr]     Checking rand_chacha v0.9.0
[INFO] [stderr]     Checking rand v0.9.1
[INFO] [stderr]     Checking kitlit_rust v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `library::isbn::ISBNType`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use library::isbn::ISBNType;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `library::isbn::ISBNType`
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use library::isbn::ISBNType;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book1_id`
[INFO] [stdout]    --> src/main.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |     let book1_id = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 100 |     let _book1_id = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 100 -     let book1_id = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 100 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book2_id`
[INFO] [stdout]    --> src/main.rs:108:9
[INFO] [stdout]     |
[INFO] [stdout] 108 |     let book2_id = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 108 |     let _book2_id = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 108 -     let book2_id = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 108 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book3_id`
[INFO] [stdout]    --> src/main.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 116 |     let book3_id = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 116 |     let _book3_id = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 116 -     let book3_id = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 116 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book3_id_repeat`
[INFO] [stdout]    --> src/main.rs:124:9
[INFO] [stdout]     |
[INFO] [stdout] 124 |     let book3_id_repeat = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out...
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 124 |     let _book3_id_repeat = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 124 -     let book3_id_repeat = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 124 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book4_id`
[INFO] [stdout]    --> src/main.rs:132:9
[INFO] [stdout]     |
[INFO] [stdout] 132 |     let book4_id = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 132 |     let _book4_id = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 132 -     let book4_id = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 132 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book5_id`
[INFO] [stdout]    --> src/main.rs:140:9
[INFO] [stdout]     |
[INFO] [stdout] 140 |     let book5_id = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 140 |     let _book5_id = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 140 -     let book5_id = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 140 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book6_id`
[INFO] [stdout]    --> src/main.rs:148:9
[INFO] [stdout]     |
[INFO] [stdout] 148 |     let book6_id = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 148 |     let _book6_id = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 148 -     let book6_id = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 148 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let mut book1 = Book::new(
[INFO] [stdout]   |         ----^^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let mut book2 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut book3 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let mut book4 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:64:9
[INFO] [stdout]    |
[INFO] [stdout] 64 |     let mut book5 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let mut book6 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book1_id`
[INFO] [stdout]    --> src/main.rs:100:9
[INFO] [stdout]     |
[INFO] [stdout] 100 |     let book1_id = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 100 |     let _book1_id = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 100 -     let book1_id = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 100 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book1).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book2_id`
[INFO] [stdout]    --> src/main.rs:108:9
[INFO] [stdout]     |
[INFO] [stdout] 108 |     let book2_id = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 108 |     let _book2_id = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 108 -     let book2_id = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 108 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book2).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book3_id`
[INFO] [stdout]    --> src/main.rs:116:9
[INFO] [stdout]     |
[INFO] [stdout] 116 |     let book3_id = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 116 |     let _book3_id = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 116 -     let book3_id = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 116 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book3_id_repeat`
[INFO] [stdout]    --> src/main.rs:124:9
[INFO] [stdout]     |
[INFO] [stdout] 124 |     let book3_id_repeat = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out...
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 124 |     let _book3_id_repeat = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 124 -     let book3_id_repeat = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 124 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book3).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book4_id`
[INFO] [stdout]    --> src/main.rs:132:9
[INFO] [stdout]     |
[INFO] [stdout] 132 |     let book4_id = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 132 |     let _book4_id = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 132 -     let book4_id = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 132 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book4).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book5_id`
[INFO] [stdout]    --> src/main.rs:140:9
[INFO] [stdout]     |
[INFO] [stdout] 140 |     let book5_id = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 140 |     let _book5_id = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 140 -     let book5_id = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 140 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book5).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `book6_id`
[INFO] [stdout]    --> src/main.rs:148:9
[INFO] [stdout]     |
[INFO] [stdout] 148 |     let book6_id = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of syn...
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] help: if this is intentional, prefix it with an underscore
[INFO] [stdout]     |
[INFO] [stdout] 148 |     let _book6_id = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |         +
[INFO] [stdout] help: you might have meant to pattern match on the similarly named constant `ID_LEN`
[INFO] [stdout]     |
[INFO] [stdout] 148 -     let book6_id = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout] 148 +     let library::catalog::ID_LEN = match my_shelf.add_book(&book6).expect("add_book should only fail if the catalog sys_ids and collection are out of sync - which shouldn't happen") {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]  --> src/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let mut book1 = Book::new(
[INFO] [stdout]   |         ----^^^^^
[INFO] [stdout]   |         |
[INFO] [stdout]   |         help: remove this `mut`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:22:9
[INFO] [stdout]    |
[INFO] [stdout] 22 |     let mut book2 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |     let mut book3 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let mut book4 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:64:9
[INFO] [stdout]    |
[INFO] [stdout] 64 |     let mut book5 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:78:9
[INFO] [stdout]    |
[INFO] [stdout] 78 |     let mut book6 = Book::new(
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.95s
[INFO] running `Command { std: "docker" "inspect" "f696538bb48c626752536154737a89f5d5ac92283da6b9a536deae38ff34fbf8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f696538bb48c626752536154737a89f5d5ac92283da6b9a536deae38ff34fbf8", kill_on_drop: false }`
[INFO] [stdout] f696538bb48c626752536154737a89f5d5ac92283da6b9a536deae38ff34fbf8
