[INFO] cloning repository https://github.com/Shyclops/calculator
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Shyclops/calculator" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShyclops%2Fcalculator", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShyclops%2Fcalculator'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dc435ff53aaaefba7a9a294180c657b9694393a3
[INFO] testing Shyclops/calculator against 1.47.0 for beta-1.48-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FShyclops%2Fcalculator" "/workspace/builds/worker-2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Shyclops/calculator on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Shyclops/calculator
[INFO] finished tweaking git repo https://github.com/Shyclops/calculator
[INFO] tweaked toml for git repo https://github.com/Shyclops/calculator written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] crate git repo https://github.com/Shyclops/calculator already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 6d79ad0e77f9d9eb143adaf10c091b554b4455f847a8fc6b5fc36ba93669489f
[INFO] running `Command { std: "docker" "start" "-a" "6d79ad0e77f9d9eb143adaf10c091b554b4455f847a8fc6b5fc36ba93669489f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6d79ad0e77f9d9eb143adaf10c091b554b4455f847a8fc6b5fc36ba93669489f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6d79ad0e77f9d9eb143adaf10c091b554b4455f847a8fc6b5fc36ba93669489f", kill_on_drop: false }`
[INFO] [stdout] 6d79ad0e77f9d9eb143adaf10c091b554b4455f847a8fc6b5fc36ba93669489f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 5240b6b2e987b34826f7cae3355273c0ea412021c60e6d9379f450679ccd625c
[INFO] running `Command { std: "docker" "start" "-a" "5240b6b2e987b34826f7cae3355273c0ea412021c60e6d9379f450679ccd625c", kill_on_drop: false }`
[INFO] [stderr]    Compiling calculator v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `operators`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operators`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `o`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:21:25
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Expression::Operator(o)    => {},
[INFO] [stdout]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_o`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:22:20
[INFO] [stdout]    |
[INFO] [stdout] 22 |             Expression::Val(v)        => output.push(ex),
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `operator`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:82:19
[INFO] [stdout]    |
[INFO] [stdout] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stdout]    |                   ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operator`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stdout]    |         ----^^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `get_precedence`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:82:4
[INFO] [stdout]    |
[INFO] [stdout] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.01s
[INFO] running `Command { std: "docker" "inspect" "5240b6b2e987b34826f7cae3355273c0ea412021c60e6d9379f450679ccd625c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5240b6b2e987b34826f7cae3355273c0ea412021c60e6d9379f450679ccd625c", kill_on_drop: false }`
[INFO] [stdout] 5240b6b2e987b34826f7cae3355273c0ea412021c60e6d9379f450679ccd625c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.47.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] db2c8349c0d208c05e084ce4442cc39ca11ba2c84585a46e7fd297c19a1e55f2
[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" "db2c8349c0d208c05e084ce4442cc39ca11ba2c84585a46e7fd297c19a1e55f2", kill_on_drop: false }`
[INFO] [stderr]    Compiling calculator v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `operators`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operators`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `o`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:21:25
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Expression::Operator(o)    => {},
[INFO] [stdout]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_o`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:22:20
[INFO] [stdout]    |
[INFO] [stdout] 22 |             Expression::Val(v)        => output.push(ex),
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `operator`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:82:19
[INFO] [stdout]    |
[INFO] [stdout] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stdout]    |                   ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operator`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stdout]    |         ----^^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `get_precedence`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:82:4
[INFO] [stdout]    |
[INFO] [stdout] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `operators`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operators`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `o`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:21:25
[INFO] [stdout]    |
[INFO] [stdout] 21 |             Expression::Operator(o)    => {},
[INFO] [stdout]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_o`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:22:20
[INFO] [stdout]    |
[INFO] [stdout] 22 |             Expression::Val(v)        => output.push(ex),
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `operator`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:82:19
[INFO] [stdout]    |
[INFO] [stdout] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stdout]    |                   ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operator`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stdout]    |
[INFO] [stdout] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stdout]    |         ----^^^^^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `get_precedence`
[INFO] [stdout]   --> src/reverse_polish_notation/parser.rs:82:4
[INFO] [stdout]    |
[INFO] [stdout] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 6 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.74s
[INFO] running `Command { std: "docker" "inspect" "db2c8349c0d208c05e084ce4442cc39ca11ba2c84585a46e7fd297c19a1e55f2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "db2c8349c0d208c05e084ce4442cc39ca11ba2c84585a46e7fd297c19a1e55f2", kill_on_drop: false }`
[INFO] [stdout] db2c8349c0d208c05e084ce4442cc39ca11ba2c84585a46e7fd297c19a1e55f2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "+1.47.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 494b8c933a0b2fce9e6718a020bf8d85b8884458219b577acebf6b89f3f8087b
[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" "494b8c933a0b2fce9e6718a020bf8d85b8884458219b577acebf6b89f3f8087b", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `operators`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stderr]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operators`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `o`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:21:25
[INFO] [stderr]    |
[INFO] [stderr] 21 |             Expression::Operator(o)    => {},
[INFO] [stderr]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_o`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `v`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:22:20
[INFO] [stderr]    |
[INFO] [stderr] 22 |             Expression::Val(v)        => output.push(ex),
[INFO] [stderr]    |                             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `operator`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:82:19
[INFO] [stderr]    |
[INFO] [stderr] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stderr]    |                   ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operator`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let mut operators: Vec<Expression> = Vec::new();
[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: function is never used: `get_precedence`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:82:4
[INFO] [stderr]    |
[INFO] [stderr] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `operators`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let mut operators: Vec<Expression> = Vec::new();
[INFO] [stderr]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operators`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `o`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:21:25
[INFO] [stderr]    |
[INFO] [stderr] 21 |             Expression::Operator(o)    => {},
[INFO] [stderr]    |                                  ^ help: if this is intentional, prefix it with an underscore: `_o`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `v`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:22:20
[INFO] [stderr]    |
[INFO] [stderr] 22 |             Expression::Val(v)        => output.push(ex),
[INFO] [stderr]    |                             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `operator`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:82:19
[INFO] [stderr]    |
[INFO] [stderr] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stderr]    |                   ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_operator`
[INFO] [stderr] 
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:17:6
[INFO] [stderr]    |
[INFO] [stderr] 17 |     let mut operators: Vec<Expression> = Vec::new();
[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: function is never used: `get_precedence`
[INFO] [stderr]   --> src/reverse_polish_notation/parser.rs:82:4
[INFO] [stderr]    |
[INFO] [stderr] 82 | fn get_precedence(operator: String) -> i8 {
[INFO] [stderr]    |    ^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 6 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/calculator-ba50dea3e3433661
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/calculator-68952fed7c038019
[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] [stderr]    Doc-tests calculator
[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 `Command { std: "docker" "inspect" "494b8c933a0b2fce9e6718a020bf8d85b8884458219b577acebf6b89f3f8087b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "494b8c933a0b2fce9e6718a020bf8d85b8884458219b577acebf6b89f3f8087b", kill_on_drop: false }`
[INFO] [stdout] 494b8c933a0b2fce9e6718a020bf8d85b8884458219b577acebf6b89f3f8087b
