[INFO] cloning repository https://github.com/victor-carvalho/jc
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/victor-carvalho/jc" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvictor-carvalho%2Fjc", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvictor-carvalho%2Fjc'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c63dd1106d285fc1c78b39faae4bedcfc7d39566
[INFO] testing victor-carvalho/jc against try#c2e32f1c9652b13ed99608599c1e855462f421f3 for pr-146098-7
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fvictor-carvalho%2Fjc" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/victor-carvalho/jc
[INFO] finished tweaking git repo https://github.com/victor-carvalho/jc
[INFO] tweaked toml for git repo https://github.com/victor-carvalho/jc written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/victor-carvalho/jc on toolchain c2e32f1c9652b13ed99608599c1e855462f421f3
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/victor-carvalho/jc 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" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 47597db4aa1b063919abc310f3761028206a01c92bb65f3209a429d66579d9f8
[INFO] running `Command { std: "docker" "start" "-a" "47597db4aa1b063919abc310f3761028206a01c92bb65f3209a429d66579d9f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "47597db4aa1b063919abc310f3761028206a01c92bb65f3209a429d66579d9f8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "47597db4aa1b063919abc310f3761028206a01c92bb65f3209a429d66579d9f8", kill_on_drop: false }`
[INFO] [stdout] 47597db4aa1b063919abc310f3761028206a01c92bb65f3209a429d66579d9f8
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 007669c54e293847985674dbc50983345fa65eb4967467baef1cdf26ef6d91a7
[INFO] running `Command { std: "docker" "start" "-a" "007669c54e293847985674dbc50983345fa65eb4967467baef1cdf26ef6d91a7", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.26
[INFO] [stderr]    Compiling libc v0.2.48
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling cc v1.0.28
[INFO] [stderr]    Compiling autocfg v0.1.2
[INFO] [stderr]    Compiling ryu v0.2.7
[INFO] [stderr]    Compiling failure_derive v0.1.5
[INFO] [stderr]    Compiling serde v1.0.85
[INFO] [stderr]    Compiling rustc-demangle v0.1.13
[INFO] [stderr]    Compiling unicode-width v0.1.5
[INFO] [stderr]    Compiling cfg-if v0.1.6
[INFO] [stderr]    Compiling textwrap v0.10.0
[INFO] [stderr]    Compiling backtrace v0.3.13
[INFO] [stderr]    Compiling bitflags v1.0.4
[INFO] [stderr]    Compiling strsim v0.7.0
[INFO] [stderr]    Compiling itoa v0.4.3
[INFO] [stderr]    Compiling clap v2.32.0
[INFO] [stderr]    Compiling atty v0.2.11
[INFO] [stderr]    Compiling backtrace-sys v0.1.28
[INFO] [stderr]    Compiling quote v0.6.11
[INFO] [stderr]    Compiling syn v0.15.26
[INFO] [stderr]    Compiling synstructure v0.10.1
[INFO] [stderr]    Compiling failure v0.1.5
[INFO] [stderr]    Compiling serde_json v1.0.37
[INFO] [stderr]    Compiling jc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:38:64
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn input_or<'a>(&self, stdin: &'a io::Stdin) -> Result<Box<BufRead + 'a>> {
[INFO] [stdout]    |                                                                ^^^^^^^^^^^^
[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(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn input_or<'a>(&self, stdin: &'a io::Stdin) -> Result<Box<dyn BufRead + 'a>> {
[INFO] [stdout]    |                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:46:67
[INFO] [stdout]    |
[INFO] [stdout] 46 |     fn output_or<'a>(&self, stdout: &'a io::Stdout) -> Result<Box<Write + 'a>> {
[INFO] [stdout]    |                                                                   ^^^^^^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 46 |     fn output_or<'a>(&self, stdout: &'a io::Stdout) -> Result<Box<dyn Write + 'a>> {
[INFO] [stdout]    |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:57:64
[INFO] [stdout]    |
[INFO] [stdout] 57 | fn print_line(element: &Value, args: &JCArgs, out_stream: &mut Write) -> Result<()> {
[INFO] [stdout]    |                                                                ^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 | fn print_line(element: &Value, args: &JCArgs, out_stream: &mut dyn Write) -> Result<()> {
[INFO] [stdout]    |                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:90:49
[INFO] [stdout]    |
[INFO] [stdout] 90 | fn print_header(args: &JCArgs, out_stream: &mut Write) -> Result<()> {
[INFO] [stdout]    |                                                 ^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 90 | fn print_header(args: &JCArgs, out_stream: &mut dyn Write) -> Result<()> {
[INFO] [stdout]    |                                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 20.55s
[INFO] running `Command { std: "docker" "inspect" "007669c54e293847985674dbc50983345fa65eb4967467baef1cdf26ef6d91a7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "007669c54e293847985674dbc50983345fa65eb4967467baef1cdf26ef6d91a7", kill_on_drop: false }`
[INFO] [stdout] 007669c54e293847985674dbc50983345fa65eb4967467baef1cdf26ef6d91a7
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] aec772ba5b0074a9179d376608e8b7ccbc0a1b37ee2c6d728175519d29c3ec21
[INFO] running `Command { std: "docker" "start" "-a" "aec772ba5b0074a9179d376608e8b7ccbc0a1b37ee2c6d728175519d29c3ec21", kill_on_drop: false }`
[INFO] [stderr]    Compiling jc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:38:64
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn input_or<'a>(&self, stdin: &'a io::Stdin) -> Result<Box<BufRead + 'a>> {
[INFO] [stdout]    |                                                                ^^^^^^^^^^^^
[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(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 38 |     fn input_or<'a>(&self, stdin: &'a io::Stdin) -> Result<Box<dyn BufRead + 'a>> {
[INFO] [stdout]    |                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:46:67
[INFO] [stdout]    |
[INFO] [stdout] 46 |     fn output_or<'a>(&self, stdout: &'a io::Stdout) -> Result<Box<Write + 'a>> {
[INFO] [stdout]    |                                                                   ^^^^^^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 46 |     fn output_or<'a>(&self, stdout: &'a io::Stdout) -> Result<Box<dyn Write + 'a>> {
[INFO] [stdout]    |                                                                   +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:57:64
[INFO] [stdout]    |
[INFO] [stdout] 57 | fn print_line(element: &Value, args: &JCArgs, out_stream: &mut Write) -> Result<()> {
[INFO] [stdout]    |                                                                ^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 57 | fn print_line(element: &Value, args: &JCArgs, out_stream: &mut dyn Write) -> Result<()> {
[INFO] [stdout]    |                                                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:90:49
[INFO] [stdout]    |
[INFO] [stdout] 90 | fn print_header(args: &JCArgs, out_stream: &mut Write) -> Result<()> {
[INFO] [stdout]    |                                                 ^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 90 | fn print_header(args: &JCArgs, out_stream: &mut dyn Write) -> Result<()> {
[INFO] [stdout]    |                                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.31s
[INFO] running `Command { std: "docker" "inspect" "aec772ba5b0074a9179d376608e8b7ccbc0a1b37ee2c6d728175519d29c3ec21", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "aec772ba5b0074a9179d376608e8b7ccbc0a1b37ee2c6d728175519d29c3ec21", kill_on_drop: false }`
[INFO] [stdout] aec772ba5b0074a9179d376608e8b7ccbc0a1b37ee2c6d728175519d29c3ec21
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+c2e32f1c9652b13ed99608599c1e855462f421f3" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 8822bbd81b0f32474911b6b1eec251c1147b2f47007d36b77d551be100c2a06e
[INFO] running `Command { std: "docker" "start" "-a" "8822bbd81b0f32474911b6b1eec251c1147b2f47007d36b77d551be100c2a06e", kill_on_drop: false }`
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/main.rs:38:64
[INFO] [stderr]    |
[INFO] [stderr] 38 |     fn input_or<'a>(&self, stdin: &'a io::Stdin) -> Result<Box<BufRead + 'a>> {
[INFO] [stderr]    |                                                                ^^^^^^^^^^^^
[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(bare_trait_objects)]` (part of `#[warn(rust_2021_compatibility)]`) on by default
[INFO] [stderr] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 38 |     fn input_or<'a>(&self, stdin: &'a io::Stdin) -> Result<Box<dyn BufRead + 'a>> {
[INFO] [stderr]    |                                                                +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/main.rs:46:67
[INFO] [stderr]    |
[INFO] [stderr] 46 |     fn output_or<'a>(&self, stdout: &'a io::Stdout) -> Result<Box<Write + 'a>> {
[INFO] [stderr]    |                                                                   ^^^^^^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 46 |     fn output_or<'a>(&self, stdout: &'a io::Stdout) -> Result<Box<dyn Write + 'a>> {
[INFO] [stderr]    |                                                                   +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/main.rs:57:64
[INFO] [stderr]    |
[INFO] [stderr] 57 | fn print_line(element: &Value, args: &JCArgs, out_stream: &mut Write) -> Result<()> {
[INFO] [stderr]    |                                                                ^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 57 | fn print_line(element: &Value, args: &JCArgs, out_stream: &mut dyn Write) -> Result<()> {
[INFO] [stderr]    |                                                                +++
[INFO] [stderr] 
[INFO] [stderr] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stderr]   --> src/main.rs:90:49
[INFO] [stderr]    |
[INFO] [stderr] 90 | fn print_header(args: &JCArgs, out_stream: &mut Write) -> Result<()> {
[INFO] [stderr]    |                                                 ^^^^^
[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] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stderr]    |
[INFO] [stderr] 90 | fn print_header(args: &JCArgs, out_stream: &mut dyn Write) -> Result<()> {
[INFO] [stderr]    |                                                 +++
[INFO] [stderr] 
[INFO] [stderr] warning: `jc` (bin "jc" test) generated 4 warnings (run `cargo fix --bin "jc" -p jc --tests` to apply 4 suggestions)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.06s
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/jc-03645b845a7caf2c)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "8822bbd81b0f32474911b6b1eec251c1147b2f47007d36b77d551be100c2a06e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8822bbd81b0f32474911b6b1eec251c1147b2f47007d36b77d551be100c2a06e", kill_on_drop: false }`
[INFO] [stdout] 8822bbd81b0f32474911b6b1eec251c1147b2f47007d36b77d551be100c2a06e
