[INFO] cloning repository https://github.com/djhworld/zipit
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/djhworld/zipit" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit'...
[INFO] [stderr] /workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit/info/: No space left on device
[WARN] Retrying crate fetch in 3 seconds (attempt 1)
[INFO] cloning repository https://github.com/djhworld/zipit
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/djhworld/zipit" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 52656bab98db2160e8d83c614ecf9690885b1a69
[INFO] checking djhworld/zipit against try#81185c2d21df0ba45fd33e65bbdce76dc0d89bd9 for pr-139646
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/djhworld/zipit on toolchain 81185c2d21df0ba45fd33e65bbdce76dc0d89bd9
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/djhworld/zipit
[INFO] finished tweaking git repo https://github.com/djhworld/zipit
[INFO] tweaked toml for git repo https://github.com/djhworld/zipit written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/djhworld/zipit 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" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "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-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] Error response from daemon: mkdir /var/lib/docker/image/overlay2/layerdb/mounts/bc65dd125f7d2f90adf4618c311abde4a1731c6dd7ccf8b7f6d4561ebdbf3e14: no space left on device
[INFO] checking djhworld/zipit against try#81185c2d21df0ba45fd33e65bbdce76dc0d89bd9 for pr-139646
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdjhworld%2Fzipit" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/djhworld/zipit on toolchain 81185c2d21df0ba45fd33e65bbdce76dc0d89bd9
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/djhworld/zipit
[INFO] finished tweaking git repo https://github.com/djhworld/zipit
[INFO] tweaked toml for git repo https://github.com/djhworld/zipit written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/djhworld/zipit 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" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "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-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e8039eb210ea8634d8382213e58db4f296da4db22ce5c97fbdee977677bd7a02
[INFO] running `Command { std: "docker" "start" "-a" "e8039eb210ea8634d8382213e58db4f296da4db22ce5c97fbdee977677bd7a02", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e8039eb210ea8634d8382213e58db4f296da4db22ce5c97fbdee977677bd7a02", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e8039eb210ea8634d8382213e58db4f296da4db22ce5c97fbdee977677bd7a02", kill_on_drop: false }`
[INFO] [stdout] e8039eb210ea8634d8382213e58db4f296da4db22ce5c97fbdee977677bd7a02
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+81185c2d21df0ba45fd33e65bbdce76dc0d89bd9" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 6fd9b63085850aa32dc7b2e9b5131a19ac66ef7cdc82f223592d28ba60308cbc
[INFO] running `Command { std: "docker" "start" "-a" "6fd9b63085850aa32dc7b2e9b5131a19ac66ef7cdc82f223592d28ba60308cbc", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.25
[INFO] [stderr]    Compiling libc v0.2.47
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling unicode-segmentation v1.2.1
[INFO] [stderr]    Compiling serde v1.0.85
[INFO] [stderr]    Compiling ryu v0.2.7
[INFO] [stderr]     Checking unicode-width v0.1.5
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking bitflags v1.0.4
[INFO] [stderr]     Checking strsim v0.7.0
[INFO] [stderr]     Checking vec_map v0.8.1
[INFO] [stderr]     Checking itoa v0.4.3
[INFO] [stderr]     Checking textwrap v0.10.0
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling quote v0.6.10
[INFO] [stderr]     Checking atty v0.2.11
[INFO] [stderr]     Checking clap v2.32.0
[INFO] [stderr]    Compiling syn v0.15.26
[INFO] [stderr]    Compiling structopt-derive v0.2.14
[INFO] [stderr]     Checking structopt v0.2.14
[INFO] [stderr]     Checking serde_json v1.0.36
[INFO] [stderr]     Checking zipit v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:14:17
[INFO] [stdout]    |
[INFO] [stdout] 14 |     writer: Box<Write>,
[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/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 14 |     writer: Box<dyn Write>,
[INFO] [stdout]    |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:48:17
[INFO] [stdout]    |
[INFO] [stdout] 48 |     writer: Box<Write>,
[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/nightly/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] 48 |     writer: Box<dyn Write>,
[INFO] [stdout]    |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:34:65
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn open_file_as_line_reader(file: &str) -> Result<BufReader<Box<Read>>> {
[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/nightly/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] 34 | fn open_file_as_line_reader(file: &str) -> Result<BufReader<Box<dyn Read>>> {
[INFO] [stdout]    |                                                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:44:56
[INFO] [stdout]    |
[INFO] [stdout] 44 | fn open_stdin_as_line_reader() -> Result<BufReader<Box<Read>>> {
[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/nightly/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] 44 | fn open_stdin_as_line_reader() -> Result<BufReader<Box<dyn Read>>> {
[INFO] [stdout]    |                                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:20:24
[INFO] [stdout]    |
[INFO] [stdout] 20 |         left_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 20 |         left_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:21:25
[INFO] [stdout]    |
[INFO] [stdout] 21 |         right_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 21 |         right_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:22:26
[INFO] [stdout]    |
[INFO] [stdout] 22 |         output: Box<&mut ZipOutput>,
[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/nightly/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] 22 |         output: Box<&mut dyn ZipOutput>,
[INFO] [stdout]    |                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/zipper/mod.rs:9:24
[INFO] [stdout]   |
[INFO] [stdout] 9 |         left_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 9 |         left_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]   |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:10:25
[INFO] [stdout]    |
[INFO] [stdout] 10 |         right_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 10 |         right_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:11:26
[INFO] [stdout]    |
[INFO] [stdout] 11 |         output: Box<&mut ZipOutput>,
[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/nightly/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] 11 |         output: Box<&mut dyn ZipOutput>,
[INFO] [stdout]    |                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:39:24
[INFO] [stdout]    |
[INFO] [stdout] 39 |         left_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 39 |         left_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:14:17
[INFO] [stdout]    |
[INFO] [stdout] 14 |     writer: Box<Write>,
[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/nightly/edition-guide/rust-2021/warnings-promoted-to-error.html>
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] help: if this is a dyn-compatible trait, use `dyn`
[INFO] [stdout]    |
[INFO] [stdout] 14 |     writer: Box<dyn Write>,
[INFO] [stdout]    |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:40:25
[INFO] [stdout]    |
[INFO] [stdout] 40 |         right_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 40 |         right_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:41:26
[INFO] [stdout]    |
[INFO] [stdout] 41 |         output: Box<&mut ZipOutput>,
[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/nightly/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] 41 |         output: Box<&mut dyn ZipOutput>,
[INFO] [stdout]    |                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:18:28
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub fn new(writer: Box<Write>) -> JsonOuput {
[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/nightly/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] 18 |     pub fn new(writer: Box<dyn Write>) -> JsonOuput {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:52:28
[INFO] [stdout]    |
[INFO] [stdout] 52 |     pub fn new(writer: Box<Write>) -> TabbedOutput {
[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/nightly/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] 52 |     pub fn new(writer: Box<dyn Write>) -> TabbedOutput {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:48:17
[INFO] [stdout]    |
[INFO] [stdout] 48 |     writer: Box<Write>,
[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/nightly/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] 48 |     writer: Box<dyn Write>,
[INFO] [stdout]    |                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:34:65
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn open_file_as_line_reader(file: &str) -> Result<BufReader<Box<Read>>> {
[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/nightly/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] 34 | fn open_file_as_line_reader(file: &str) -> Result<BufReader<Box<dyn Read>>> {
[INFO] [stdout]    |                                                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:44:56
[INFO] [stdout]    |
[INFO] [stdout] 44 | fn open_stdin_as_line_reader() -> Result<BufReader<Box<Read>>> {
[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/nightly/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] 44 | fn open_stdin_as_line_reader() -> Result<BufReader<Box<dyn Read>>> {
[INFO] [stdout]    |                                                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:20:24
[INFO] [stdout]    |
[INFO] [stdout] 20 |         left_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 20 |         left_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:21:25
[INFO] [stdout]    |
[INFO] [stdout] 21 |         right_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 21 |         right_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:22:26
[INFO] [stdout]    |
[INFO] [stdout] 22 |         output: Box<&mut ZipOutput>,
[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/nightly/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] 22 |         output: Box<&mut dyn ZipOutput>,
[INFO] [stdout]    |                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]  --> src/zipper/mod.rs:9:24
[INFO] [stdout]   |
[INFO] [stdout] 9 |         left_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 9 |         left_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]   |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:10:25
[INFO] [stdout]    |
[INFO] [stdout] 10 |         right_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 10 |         right_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:11:26
[INFO] [stdout]    |
[INFO] [stdout] 11 |         output: Box<&mut ZipOutput>,
[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/nightly/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] 11 |         output: Box<&mut dyn ZipOutput>,
[INFO] [stdout]    |                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:39:24
[INFO] [stdout]    |
[INFO] [stdout] 39 |         left_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 39 |         left_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                        +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:40:25
[INFO] [stdout]    |
[INFO] [stdout] 40 |         right_iter: Box<Iterator<Item = Result<String>>>,
[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/nightly/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] 40 |         right_iter: Box<dyn Iterator<Item = Result<String>>>,
[INFO] [stdout]    |                         +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/mod.rs:41:26
[INFO] [stdout]    |
[INFO] [stdout] 41 |         output: Box<&mut ZipOutput>,
[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/nightly/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] 41 |         output: Box<&mut dyn ZipOutput>,
[INFO] [stdout]    |                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:18:28
[INFO] [stdout]    |
[INFO] [stdout] 18 |     pub fn new(writer: Box<Write>) -> JsonOuput {
[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/nightly/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] 18 |     pub fn new(writer: Box<dyn Write>) -> JsonOuput {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/zipper/render.rs:52:28
[INFO] [stdout]    |
[INFO] [stdout] 52 |     pub fn new(writer: Box<Write>) -> TabbedOutput {
[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/nightly/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] 52 |     pub fn new(writer: Box<dyn Write>) -> TabbedOutput {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:37:60
[INFO] [stdout]    |
[INFO] [stdout] 37 |             let buffer = BufReader::new(Box::new(f) as Box<Read>);
[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/nightly/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] 37 |             let buffer = BufReader::new(Box::new(f) as Box<dyn Read>);
[INFO] [stdout]    |                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:47:61
[INFO] [stdout]    |
[INFO] [stdout] 47 |     let buffer = BufReader::new(Box::new(stdin_lock) as Box<Read>);
[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/nightly/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] 47 |     let buffer = BufReader::new(Box::new(stdin_lock) as Box<dyn Read>);
[INFO] [stdout]    |                                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:59:37
[INFO] [stdout]    |
[INFO] [stdout] 59 |     let reader_right: BufReader<Box<Read>> = match &opt.right_file {
[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/nightly/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] 59 |     let reader_right: BufReader<Box<dyn Read>> = match &opt.right_file {
[INFO] [stdout]    |                                     +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:68:28
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let renderer: Box<&mut ZipOutput> = match opt.json {
[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/nightly/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] 68 |     let renderer: Box<&mut dyn ZipOutput> = match opt.json {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:73:21
[INFO] [stdout]    |
[INFO] [stdout] 73 |     let zipper: Box<Zipper> = match opt.cycle {
[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/nightly/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] 73 |     let zipper: Box<dyn Zipper> = match opt.cycle {
[INFO] [stdout]    |                     +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:37:60
[INFO] [stdout]    |
[INFO] [stdout] 37 |             let buffer = BufReader::new(Box::new(f) as Box<Read>);
[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/nightly/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] 37 |             let buffer = BufReader::new(Box::new(f) as Box<dyn Read>);
[INFO] [stdout]    |                                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:47:61
[INFO] [stdout]    |
[INFO] [stdout] 47 |     let buffer = BufReader::new(Box::new(stdin_lock) as Box<Read>);
[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/nightly/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] 47 |     let buffer = BufReader::new(Box::new(stdin_lock) as Box<dyn Read>);
[INFO] [stdout]    |                                                             +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:59:37
[INFO] [stdout]    |
[INFO] [stdout] 59 |     let reader_right: BufReader<Box<Read>> = match &opt.right_file {
[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/nightly/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] 59 |     let reader_right: BufReader<Box<dyn Read>> = match &opt.right_file {
[INFO] [stdout]    |                                     +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:68:28
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let renderer: Box<&mut ZipOutput> = match opt.json {
[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/nightly/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] 68 |     let renderer: Box<&mut dyn ZipOutput> = match opt.json {
[INFO] [stdout]    |                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/main.rs:73:21
[INFO] [stdout]    |
[INFO] [stdout] 73 |     let zipper: Box<Zipper> = match opt.cycle {
[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/nightly/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] 73 |     let zipper: Box<dyn Zipper> = match opt.cycle {
[INFO] [stdout]    |                     +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.68s
[INFO] running `Command { std: "docker" "inspect" "6fd9b63085850aa32dc7b2e9b5131a19ac66ef7cdc82f223592d28ba60308cbc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6fd9b63085850aa32dc7b2e9b5131a19ac66ef7cdc82f223592d28ba60308cbc", kill_on_drop: false }`
[INFO] [stdout] 6fd9b63085850aa32dc7b2e9b5131a19ac66ef7cdc82f223592d28ba60308cbc