[INFO] fetching crate buspirate 0.1.0...
[INFO] testing buspirate-0.1.0 against beta-2020-10-09 for beta-1.48-1
[INFO] extracting crate buspirate 0.1.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate buspirate 0.1.0 on toolchain beta-2020-10-09
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate buspirate 0.1.0
[INFO] finished tweaking crates.io crate buspirate 0.1.0
[INFO] tweaked toml for crates.io crate buspirate 0.1.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2020-10-09" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 78bb72fac408ba6b9f0f0ca051d3883d1a4b2d8ed97d60b89d4c493653cc48ea
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "78bb72fac408ba6b9f0f0ca051d3883d1a4b2d8ed97d60b89d4c493653cc48ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "78bb72fac408ba6b9f0f0ca051d3883d1a4b2d8ed97d60b89d4c493653cc48ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "78bb72fac408ba6b9f0f0ca051d3883d1a4b2d8ed97d60b89d4c493653cc48ea", kill_on_drop: false }`
[INFO] [stdout] 78bb72fac408ba6b9f0f0ca051d3883d1a4b2d8ed97d60b89d4c493653cc48ea
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0519edad60fc710ebdc28a38b3407bb2da40e42a7d438b125e00204bee24309b
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "0519edad60fc710ebdc28a38b3407bb2da40e42a7d438b125e00204bee24309b", kill_on_drop: false }`
[INFO] [stderr]    Compiling nb v0.1.3
[INFO] [stderr]    Compiling embedded-hal v0.2.4
[INFO] [stderr]    Compiling buspirate v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.79s
[INFO] running `Command { std: "docker" "inspect" "0519edad60fc710ebdc28a38b3407bb2da40e42a7d438b125e00204bee24309b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0519edad60fc710ebdc28a38b3407bb2da40e42a7d438b125e00204bee24309b", kill_on_drop: false }`
[INFO] [stdout] 0519edad60fc710ebdc28a38b3407bb2da40e42a7d438b125e00204bee24309b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c4c896e26a5ca531664410f7545198676559d2fdf8b97b7a46d8e378237e521b
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c4c896e26a5ca531664410f7545198676559d2fdf8b97b7a46d8e378237e521b", kill_on_drop: false }`
[INFO] [stderr]    Compiling buspirate v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.71s
[INFO] running `Command { std: "docker" "inspect" "c4c896e26a5ca531664410f7545198676559d2fdf8b97b7a46d8e378237e521b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c4c896e26a5ca531664410f7545198676559d2fdf8b97b7a46d8e378237e521b", kill_on_drop: false }`
[INFO] [stdout] c4c896e26a5ca531664410f7545198676559d2fdf8b97b7a46d8e378237e521b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2020-10-09" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 921ab344f7268bdf0e342144e3210e4dd3e4a22fc1ab295cfa31dd95c0f635ef
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "921ab344f7268bdf0e342144e3210e4dd3e4a22fc1ab295cfa31dd95c0f635ef", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stdout] running 0 tests
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/buspirate-1036e8d0214ff17d
[INFO] [stdout] 
[INFO] [stderr]    Doc-tests buspirate
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 6 tests
[INFO] [stdout] test src/lib.rs - (line 49) ... FAILED
[INFO] [stdout] test src/bitbang.rs - bitbang (line 6) ... FAILED
[INFO] [stdout] test src/spi.rs - spi (line 7) ... FAILED
[INFO] [stdout] test src/lib.rs - (line 41) ... FAILED
[INFO] [stdout] test src/lib.rs - BusPirate (line 72) ... FAILED
[INFO] [stdout] test src/lib.rs - (line 22) ... FAILED
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout] 
[INFO] [stdout] ---- src/lib.rs - (line 49) stdout ----
[INFO] [stdout] error[E0425]: cannot find value `bp` in this scope
[INFO] [stdout]  --> src/lib.rs:50:11
[INFO] [stdout]   |
[INFO] [stdout] 3 | let spi = bp.to_spi()?;
[INFO] [stdout]   |           ^^ not found in this scope
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]  --> src/lib.rs:50:11
[INFO] [stdout]   |
[INFO] [stdout] 2 | / fn main() {
[INFO] [stdout] 3 | | let spi = bp.to_spi()?;
[INFO] [stdout]   | |           ^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 4 | | }
[INFO] [stdout]   | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]   = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0425.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/bitbang.rs - bitbang (line 6) stdout ----
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `BusPirate`
[INFO] [stdout]  --> src/bitbang.rs:7:10
[INFO] [stdout]   |
[INFO] [stdout] 3 | let bp = BusPirate::new();
[INFO] [stdout]   |          ^^^^^^^^^ not found in this scope
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this struct
[INFO] [stdout]   |
[INFO] [stdout] 2 | use buspirate::BusPirate;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]  --> src/bitbang.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 2 | / fn main() {
[INFO] [stdout] 3 | | let bp = BusPirate::new();
[INFO] [stdout] 4 | | let bb = bp.to_bitbang()?;
[INFO] [stdout]   | |          ^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 5 | | }
[INFO] [stdout]   | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]   = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0433.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/spi.rs - spi (line 7) stdout ----
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `BusPirate`
[INFO] [stdout]  --> src/spi.rs:8:10
[INFO] [stdout]   |
[INFO] [stdout] 3 | let bp = BusPirate::new();
[INFO] [stdout]   |          ^^^^^^^^^ not found in this scope
[INFO] [stdout]   |
[INFO] [stdout] help: consider importing this struct
[INFO] [stdout]   |
[INFO] [stdout] 2 | use buspirate::BusPirate;
[INFO] [stdout]   |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]  --> src/spi.rs:9:10
[INFO] [stdout]   |
[INFO] [stdout] 2 | / fn main() {
[INFO] [stdout] 3 | | let bp = BusPirate::new();
[INFO] [stdout] 4 | | let bb = bp.to_bitbang()?;
[INFO] [stdout]   | |          ^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 5 | | let bspi = bb.to_spi()?;
[INFO] [stdout] 6 | | }
[INFO] [stdout]   | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]   = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]  --> src/spi.rs:10:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | / fn main() {
[INFO] [stdout] 3 | | let bp = BusPirate::new();
[INFO] [stdout] 4 | | let bb = bp.to_bitbang()?;
[INFO] [stdout] 5 | | let bspi = bb.to_spi()?;
[INFO] [stdout]   | |            ^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 6 | | }
[INFO] [stdout]   | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]   = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0433.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/lib.rs - (line 41) stdout ----
[INFO] [stdout] error[E0425]: cannot find value `bp` in this scope
[INFO] [stdout]  --> src/lib.rs:42:10
[INFO] [stdout]   |
[INFO] [stdout] 3 | let bb = bp.init()?;
[INFO] [stdout]   |          ^^ not found in this scope
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]  --> src/lib.rs:42:10
[INFO] [stdout]   |
[INFO] [stdout] 2 | / fn main() {
[INFO] [stdout] 3 | | let bb = bp.init()?;
[INFO] [stdout]   | |          ^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 4 | | }
[INFO] [stdout]   | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]   = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0425.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/lib.rs - BusPirate (line 72) stdout ----
[INFO] [stdout] error[E0425]: cannot find value `bp` in this scope
[INFO] [stdout]  --> src/lib.rs:73:10
[INFO] [stdout]   |
[INFO] [stdout] 3 | let bb = bp.to_bitbang()?;
[INFO] [stdout]   |          ^^ not found in this scope
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]  --> src/lib.rs:73:10
[INFO] [stdout]   |
[INFO] [stdout] 2 | / fn main() {
[INFO] [stdout] 3 | | let bb = bp.to_bitbang()?;
[INFO] [stdout]   | |          ^^^^^^^^^^^^^^^^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 4 | | }
[INFO] [stdout]   | |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]   |
[INFO] [stdout]   = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]   = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0425.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] ---- src/lib.rs - (line 22) stdout ----
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `Serial`
[INFO] [stdout]  --> src/lib.rs:23:12
[INFO] [stdout]   |
[INFO] [stdout] 3 | let port = Serial::new(
[INFO] [stdout]   |            ^^^^^^ use of undeclared type `Serial`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout]  --> src/lib.rs:26:20
[INFO] [stdout]   |
[INFO] [stdout] 6 |         baud_rate: serial_embedded_hal::BaudRate::Baud115200,
[INFO] [stdout]   |                    ^^^^^^^^^^^^^^^^^^^ use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout]  --> src/lib.rs:27:20
[INFO] [stdout]   |
[INFO] [stdout] 7 |         char_size: serial_embedded_hal::CharSize::Bits8,
[INFO] [stdout]   |                    ^^^^^^^^^^^^^^^^^^^ use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout]  --> src/lib.rs:28:17
[INFO] [stdout]   |
[INFO] [stdout] 8 |         parity: serial_embedded_hal::Parity::ParityNone,
[INFO] [stdout]   |                 ^^^^^^^^^^^^^^^^^^^ use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout]  --> src/lib.rs:29:20
[INFO] [stdout]   |
[INFO] [stdout] 9 |         stop_bits: serial_embedded_hal::StopBits::Stop1,
[INFO] [stdout]   |                    ^^^^^^^^^^^^^^^^^^^ use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout]   --> src/lib.rs:30:23
[INFO] [stdout]    |
[INFO] [stdout] 10 |         flow_control: serial_embedded_hal::FlowControl::FlowNone,
[INFO] [stdout]    |                       ^^^^^^^^^^^^^^^^^^^ use of undeclared crate or module `serial_embedded_hal`
[INFO] [stdout] 
[INFO] [stdout] error[E0422]: cannot find struct, variant or union type `PortSettings` in this scope
[INFO] [stdout]  --> src/lib.rs:25:6
[INFO] [stdout]   |
[INFO] [stdout] 5 |     &PortSettings {
[INFO] [stdout]   |      ^^^^^^^^^^^^ not found in this scope
[INFO] [stdout] 
[INFO] [stdout] error[E0433]: failed to resolve: use of undeclared type `BusPirate`
[INFO] [stdout]   --> src/lib.rs:34:10
[INFO] [stdout]    |
[INFO] [stdout] 14 | let bp = BusPirate::new(tx, rx);
[INFO] [stdout]    |          ^^^^^^^^^ not found in this scope
[INFO] [stdout]    |
[INFO] [stdout] help: consider importing this struct
[INFO] [stdout]    |
[INFO] [stdout] 2  | use buspirate::BusPirate;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `Try`)
[INFO] [stdout]   --> src/lib.rs:23:12
[INFO] [stdout]    |
[INFO] [stdout] 2  |  / fn main() {
[INFO] [stdout] 3  |  | let port = Serial::new(
[INFO] [stdout]    |  |____________^
[INFO] [stdout] 4  | ||     "/dev/ttyUSB0",
[INFO] [stdout] 5  | ||     &PortSettings {
[INFO] [stdout] 6  | ||         baud_rate: serial_embedded_hal::BaudRate::Baud115200,
[INFO] [stdout] ...  ||
[INFO] [stdout] 11 | ||     },
[INFO] [stdout] 12 | || )?;
[INFO] [stdout]    | ||__^ cannot use the `?` operator in a function that returns `()`
[INFO] [stdout] 13 |  | let (tx, rx) = port.split();
[INFO] [stdout] 14 |  | let bp = BusPirate::new(tx, rx);
[INFO] [stdout] 15 |  | }
[INFO] [stdout]    |  |_- this function should return `Result` or `Option` to accept `?`
[INFO] [stdout]    |
[INFO] [stdout]    = help: the trait `Try` is not implemented for `()`
[INFO] [stdout]    = note: required by `from_error`
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 9 previous errors
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0422, E0433.
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] Couldn't compile the test.
[INFO] [stdout] 
[INFO] [stdout] failures:
[INFO] [stdout]     src/bitbang.rs - bitbang (line 6)
[INFO] [stdout]     src/lib.rs - (line 22)
[INFO] [stdout]     src/lib.rs - (line 41)
[INFO] [stdout]     src/lib.rs - (line 49)
[INFO] [stdout]     src/lib.rs - BusPirate (line 72)
[INFO] [stdout]     src/spi.rs - spi (line 7)
[INFO] [stdout] 
[INFO] [stdout] test result: FAILED. 0 passed; 6 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr] error: test failed, to rerun pass '--doc'
[INFO] running `Command { std: "docker" "inspect" "921ab344f7268bdf0e342144e3210e4dd3e4a22fc1ab295cfa31dd95c0f635ef", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "921ab344f7268bdf0e342144e3210e4dd3e4a22fc1ab295cfa31dd95c0f635ef", kill_on_drop: false }`
[INFO] [stdout] 921ab344f7268bdf0e342144e3210e4dd3e4a22fc1ab295cfa31dd95c0f635ef
