[INFO] fetching crate ferris-extensions 0.1.0...
[INFO] testing ferris-extensions-0.1.0 against 1.44.0 for beta-1.45-1
[INFO] extracting crate ferris-extensions 0.1.0 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate ferris-extensions 0.1.0 on toolchain 1.44.0
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate ferris-extensions 0.1.0
[INFO] finished tweaking crates.io crate ferris-extensions 0.1.0
[INFO] tweaked toml for crates.io crate ferris-extensions 0.1.0 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+1.44.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "build" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 83bff7f0df0d55b70f920d47562dfd3bbd64b3ec86ebebe6cc6c50031f74122c
[INFO] running `"docker" "start" "-a" "83bff7f0df0d55b70f920d47562dfd3bbd64b3ec86ebebe6cc6c50031f74122c"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling Inflector v0.11.4
[INFO] [stderr]    Compiling syn v1.0.30
[INFO] [stderr]    Compiling ferris-extensions v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `std::borrow::Borrow`
[INFO] [stderr]  --> src/lib.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::borrow::Borrow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Add`
[INFO] [stderr]  --> src/lib.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::Add;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `syn::export::Formatter`
[INFO] [stderr]  --> src/lib.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use syn::export::Formatter;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::fmt::Error`
[INFO] [stderr]  --> src/lib.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::fmt::Error;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `proc_macro2::TokenTree::Ident`
[INFO] [stderr]  --> src/lib.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 | use proc_macro2::TokenTree::Ident;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]   --> src/lib.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]   --> src/lib.rs:31:26
[INFO] [stderr]    |
[INFO] [stderr] 31 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]    |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]    --> src/lib.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]    --> src/lib.rs:135:26
[INFO] [stderr]     |
[INFO] [stderr] 135 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]     |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: 9 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 11.78s
[INFO] running `"docker" "inspect" "83bff7f0df0d55b70f920d47562dfd3bbd64b3ec86ebebe6cc6c50031f74122c"`
[INFO] running `"docker" "rm" "-f" "83bff7f0df0d55b70f920d47562dfd3bbd64b3ec86ebebe6cc6c50031f74122c"`
[INFO] [stdout] 83bff7f0df0d55b70f920d47562dfd3bbd64b3ec86ebebe6cc6c50031f74122c
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "test" "--frozen" "--no-run"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] a659c7c6a45abfdffe3a2b0d7c9c3c4d462b01d272d22fa7d602930e399c4a85
[INFO] running `"docker" "start" "-a" "a659c7c6a45abfdffe3a2b0d7c9c3c4d462b01d272d22fa7d602930e399c4a85"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling ferris-extensions v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused import: `std::borrow::Borrow`
[INFO] [stderr]  --> src/lib.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::borrow::Borrow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Add`
[INFO] [stderr]  --> src/lib.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::Add;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `syn::export::Formatter`
[INFO] [stderr]  --> src/lib.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use syn::export::Formatter;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::fmt::Error`
[INFO] [stderr]  --> src/lib.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::fmt::Error;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `proc_macro2::TokenTree::Ident`
[INFO] [stderr]  --> src/lib.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 | use proc_macro2::TokenTree::Ident;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]   --> src/lib.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]   --> src/lib.rs:31:26
[INFO] [stderr]    |
[INFO] [stderr] 31 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]    |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]    --> src/lib.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]    --> src/lib.rs:135:26
[INFO] [stderr]     |
[INFO] [stderr] 135 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]     |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: 9 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::borrow::Borrow`
[INFO] [stderr]  --> src/lib.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::borrow::Borrow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Add`
[INFO] [stderr]  --> src/lib.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::Add;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `syn::export::Formatter`
[INFO] [stderr]  --> src/lib.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use syn::export::Formatter;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::fmt::Error`
[INFO] [stderr]  --> src/lib.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::fmt::Error;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `proc_macro2::TokenTree::Ident`
[INFO] [stderr]  --> src/lib.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 | use proc_macro2::TokenTree::Ident;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]   --> src/lib.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]   --> src/lib.rs:31:26
[INFO] [stderr]    |
[INFO] [stderr] 31 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]    |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]    --> src/lib.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]    --> src/lib.rs:135:26
[INFO] [stderr]     |
[INFO] [stderr] 135 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]     |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: 9 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.52s
[INFO] running `"docker" "inspect" "a659c7c6a45abfdffe3a2b0d7c9c3c4d462b01d272d22fa7d602930e399c4a85"`
[INFO] running `"docker" "rm" "-f" "a659c7c6a45abfdffe3a2b0d7c9c3c4d462b01d272d22fa7d602930e399c4a85"`
[INFO] [stdout] a659c7c6a45abfdffe3a2b0d7c9c3c4d462b01d272d22fa7d602930e399c4a85
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "MAP_USER_ID=0" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.44.0" "test" "--frozen"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 7121a5d2d6e25768eb6274d6b8776fea46bb18282cc78b0db72ecc4c36aa08aa
[INFO] running `"docker" "start" "-a" "7121a5d2d6e25768eb6274d6b8776fea46bb18282cc78b0db72ecc4c36aa08aa"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr] warning: unused import: `std::borrow::Borrow`
[INFO] [stderr]  --> src/lib.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::borrow::Borrow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Add`
[INFO] [stderr]  --> src/lib.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::Add;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::borrow::Borrow`
[INFO] [stderr]  --> src/lib.rs:2:5
[INFO] [stderr]   |
[INFO] [stderr] 2 | use std::borrow::Borrow;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `syn::export::Formatter`
[INFO] [stderr]  --> src/lib.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use syn::export::Formatter;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::ops::Add`
[INFO] [stderr]  --> src/lib.rs:5:5
[INFO] [stderr]   |
[INFO] [stderr] 5 | use std::ops::Add;
[INFO] [stderr]   |     ^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::fmt::Error`
[INFO] [stderr]  --> src/lib.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::fmt::Error;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `syn::export::Formatter`
[INFO] [stderr]  --> src/lib.rs:6:5
[INFO] [stderr]   |
[INFO] [stderr] 6 | use syn::export::Formatter;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `std::fmt::Error`
[INFO] [stderr]  --> src/lib.rs:8:5
[INFO] [stderr]   |
[INFO] [stderr] 8 | use std::fmt::Error;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `proc_macro2::TokenTree::Ident`
[INFO] [stderr]  --> src/lib.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 | use proc_macro2::TokenTree::Ident;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused import: `proc_macro2::TokenTree::Ident`
[INFO] [stderr]  --> src/lib.rs:9:5
[INFO] [stderr]   |
[INFO] [stderr] 9 | use proc_macro2::TokenTree::Ident;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]   --> src/lib.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]   --> src/lib.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]    |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]   --> src/lib.rs:31:26
[INFO] [stderr]    |
[INFO] [stderr] 31 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]    |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]    --> src/lib.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]    --> src/lib.rs:135:26
[INFO] [stderr]     |
[INFO] [stderr] 135 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]     |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: 9 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]   --> src/lib.rs:31:26
[INFO] [stderr]    |
[INFO] [stderr] 31 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]    |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `attr_args`
[INFO] [stderr]    --> src/lib.rs:120:9
[INFO] [stderr]     |
[INFO] [stderr] 120 |     let attr_args = syn::parse_macro_input!(attrs as syn::AttributeArgs);
[INFO] [stderr]     |         ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_attr_args`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `arrow`
[INFO] [stderr]    --> src/lib.rs:135:26
[INFO] [stderr]     |
[INFO] [stderr] 135 |         ReturnType::Type(arrow, box_type) => {
[INFO] [stderr]     |                          ^^^^^ help: if this is intentional, prefix it with an underscore: `_arrow`
[INFO] [stderr] 
[INFO] [stderr] warning: 9 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.08s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/ferris_extensions-b88d708eab567c45
[INFO] [stderr]    Doc-tests ferris-extensions
[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
[INFO] [stdout] 
[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
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "7121a5d2d6e25768eb6274d6b8776fea46bb18282cc78b0db72ecc4c36aa08aa"`
[INFO] running `"docker" "rm" "-f" "7121a5d2d6e25768eb6274d6b8776fea46bb18282cc78b0db72ecc4c36aa08aa"`
[INFO] [stdout] 7121a5d2d6e25768eb6274d6b8776fea46bb18282cc78b0db72ecc4c36aa08aa