[INFO] fetching crate taiwan-id 1.0.0...
[INFO] testing taiwan-id-1.0.0 against 1.95.0 for beta-1.96-2
[INFO] extracting crate taiwan-id 1.0.0 into /workspace/builds/worker-1-tc1/source
[INFO] started tweaking crates.io crate taiwan-id 1.0.0
[INFO] finished tweaking crates.io crate taiwan-id 1.0.0
[INFO] tweaked toml for crates.io crate taiwan-id 1.0.0 written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate taiwan-id 1.0.0 on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 15 packages to latest compatible versions
[INFO] [stderr]       Adding rand v0.7.3 (available: v0.10.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 32fc30d78bfa4a7dbc98e39d42a851754140cba61bec8fd89b11169e45271172
[INFO] running `Command { std: "docker" "start" "-a" "32fc30d78bfa4a7dbc98e39d42a851754140cba61bec8fd89b11169e45271172", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "32fc30d78bfa4a7dbc98e39d42a851754140cba61bec8fd89b11169e45271172", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32fc30d78bfa4a7dbc98e39d42a851754140cba61bec8fd89b11169e45271172", kill_on_drop: false }`
[INFO] [stdout] 32fc30d78bfa4a7dbc98e39d42a851754140cba61bec8fd89b11169e45271172
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7773482f0c94d54e5867f0cd315698f235a7e5cbd0463b4967f4e11c77bb93d2
[INFO] running `Command { std: "docker" "start" "-a" "7773482f0c94d54e5867f0cd315698f235a7e5cbd0463b4967f4e11c77bb93d2", kill_on_drop: false }`
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling taiwan-id v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:16:15
[INFO] [stdout]    |
[INFO] [stdout] 16 |     if let 'A'...'Z' = first_letter {
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:26:19
[INFO] [stdout]    |
[INFO] [stdout] 26 |         if let '0'...'9' = c {
[INFO] [stdout]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:80:15
[INFO] [stdout]    |
[INFO] [stdout] 80 |     if let 'A'...'Z' = first_letter {
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:89:19
[INFO] [stdout]    |
[INFO] [stdout] 89 |         if let '0'...'9' = i {
[INFO] [stdout]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.96s
[INFO] running `Command { std: "docker" "inspect" "7773482f0c94d54e5867f0cd315698f235a7e5cbd0463b4967f4e11c77bb93d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7773482f0c94d54e5867f0cd315698f235a7e5cbd0463b4967f4e11c77bb93d2", kill_on_drop: false }`
[INFO] [stdout] 7773482f0c94d54e5867f0cd315698f235a7e5cbd0463b4967f4e11c77bb93d2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3eb3136991ef94f85a21d7f3710a0aa1732b7102d10ff9c8b7ae1c9d2a23bf31
[INFO] running `Command { std: "docker" "start" "-a" "3eb3136991ef94f85a21d7f3710a0aa1732b7102d10ff9c8b7ae1c9d2a23bf31", kill_on_drop: false }`
[INFO] [stderr]    Compiling taiwan-id v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:16:15
[INFO] [stdout]    |
[INFO] [stdout] 16 |     if let 'A'...'Z' = first_letter {
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:26:19
[INFO] [stdout]    |
[INFO] [stdout] 26 |         if let '0'...'9' = c {
[INFO] [stdout]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:80:15
[INFO] [stdout]    |
[INFO] [stdout] 80 |     if let 'A'...'Z' = first_letter {
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:89:19
[INFO] [stdout]    |
[INFO] [stdout] 89 |         if let '0'...'9' = i {
[INFO] [stdout]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:16:15
[INFO] [stdout]    |
[INFO] [stdout] 16 |     if let 'A'...'Z' = first_letter {
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:26:19
[INFO] [stdout]    |
[INFO] [stdout] 26 |         if let '0'...'9' = c {
[INFO] [stdout]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:80:15
[INFO] [stdout]    |
[INFO] [stdout] 80 |     if let 'A'...'Z' = first_letter {
[INFO] [stdout]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `...` range patterns are deprecated
[INFO] [stdout]   --> src/lib.rs:89:19
[INFO] [stdout]    |
[INFO] [stdout] 89 |         if let '0'...'9' = i {
[INFO] [stdout]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stdout]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.41s
[INFO] running `Command { std: "docker" "inspect" "3eb3136991ef94f85a21d7f3710a0aa1732b7102d10ff9c8b7ae1c9d2a23bf31", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3eb3136991ef94f85a21d7f3710a0aa1732b7102d10ff9c8b7ae1c9d2a23bf31", kill_on_drop: false }`
[INFO] [stdout] 3eb3136991ef94f85a21d7f3710a0aa1732b7102d10ff9c8b7ae1c9d2a23bf31
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] df1dd348c3d22d9bf0ddbdebd358ec4dee7d48e0f78294db312d0cbd0e29557b
[INFO] running `Command { std: "docker" "start" "-a" "df1dd348c3d22d9bf0ddbdebd358ec4dee7d48e0f78294db312d0cbd0e29557b", kill_on_drop: false }`
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:16:15
[INFO] [stderr]    |
[INFO] [stderr] 16 |     if let 'A'...'Z' = first_letter {
[INFO] [stderr]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:26:19
[INFO] [stderr]    |
[INFO] [stderr] 26 |         if let '0'...'9' = c {
[INFO] [stderr]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:80:15
[INFO] [stderr]    |
[INFO] [stderr] 80 |     if let 'A'...'Z' = first_letter {
[INFO] [stderr]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:89:19
[INFO] [stderr]    |
[INFO] [stderr] 89 |         if let '0'...'9' = i {
[INFO] [stderr]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] 
[INFO] [stderr] warning: `taiwan-id` (lib) generated 4 warnings (run `cargo fix --lib -p taiwan-id` to apply 4 suggestions)
[INFO] [stderr] warning: `taiwan-id` (lib test) generated 4 warnings (4 duplicates)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.05s
[INFO] [stderr]      Running unittests src/lib.rs (/opt/rustwide/target/debug/deps/taiwan_id-09825ff9ae5d6fb1)
[INFO] [stdout] 
[INFO] [stdout] running 2 tests
[INFO] [stderr]    Doc-tests taiwan_id
[INFO] [stdout] test tests::is_valid ... ok
[INFO] [stdout] test tests::generate ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:16:15
[INFO] [stderr]    |
[INFO] [stderr] 16 |     if let 'A'...'Z' = first_letter {
[INFO] [stderr]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr]    = note: `#[warn(ellipsis_inclusive_range_patterns)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:26:19
[INFO] [stderr]    |
[INFO] [stderr] 26 |         if let '0'...'9' = c {
[INFO] [stderr]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:80:15
[INFO] [stderr]    |
[INFO] [stderr] 80 |     if let 'A'...'Z' = first_letter {
[INFO] [stderr]    |               ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] 
[INFO] [stderr] warning: `...` range patterns are deprecated
[INFO] [stderr]   --> src/lib.rs:89:19
[INFO] [stderr]    |
[INFO] [stderr] 89 |         if let '0'...'9' = i {
[INFO] [stderr]    |                   ^^^ help: use `..=` for an inclusive range
[INFO] [stderr]    |
[INFO] [stderr]    = warning: this is accepted in the current edition (Rust 2018) but is a hard error in Rust 2021!
[INFO] [stderr]    = note: for more information, see <https://doc.rust-lang.org/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stderr] 
[INFO] [stderr] warning: 4 warnings emitted
[INFO] [stderr] 
[INFO] [stdout] 
[INFO] [stdout] running 2 tests
[INFO] [stdout] test src/lib.rs - is_valid (line 5) ... ok
[INFO] [stdout] test src/lib.rs - generate_prefix (line 48) ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.28s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "df1dd348c3d22d9bf0ddbdebd358ec4dee7d48e0f78294db312d0cbd0e29557b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "df1dd348c3d22d9bf0ddbdebd358ec4dee7d48e0f78294db312d0cbd0e29557b", kill_on_drop: false }`
[INFO] [stdout] df1dd348c3d22d9bf0ddbdebd358ec4dee7d48e0f78294db312d0cbd0e29557b
