[INFO] fetching crate strand 0.1.2...
[INFO] building strand-0.1.2 against try#4987e9d4227139400384ab59296ffee3b0fb1183 for pr-146237-2
[INFO] extracting crate strand 0.1.2 into /workspace/builds/worker-1-tc2/source
[INFO] started tweaking crates.io crate strand 0.1.2
[INFO] finished tweaking crates.io crate strand 0.1.2
[INFO] tweaked toml for crates.io crate strand 0.1.2 written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate strand 0.1.2 on toolchain 4987e9d4227139400384ab59296ffee3b0fb1183
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e83c6a93944541fe6606a83a31a7ee96bdfaaeb34aa9ca4a15beede155cc979b
[INFO] running `Command { std: "docker" "start" "-a" "e83c6a93944541fe6606a83a31a7ee96bdfaaeb34aa9ca4a15beede155cc979b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e83c6a93944541fe6606a83a31a7ee96bdfaaeb34aa9ca4a15beede155cc979b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e83c6a93944541fe6606a83a31a7ee96bdfaaeb34aa9ca4a15beede155cc979b", kill_on_drop: false }`
[INFO] [stdout] e83c6a93944541fe6606a83a31a7ee96bdfaaeb34aa9ca4a15beede155cc979b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 71e1d905722f343e2c90f81d67c86a04af94eed2fd9b4ad84452b0e375027297
[INFO] running `Command { std: "docker" "start" "-a" "71e1d905722f343e2c90f81d67c86a04af94eed2fd9b4ad84452b0e375027297", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stderr]    Compiling strand v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:24:42
[INFO] [stdout]    |
[INFO] [stdout] 24 |   fn evolve<'a>(&'a mut self, event: &'a Event<T = T>) -> Result<(), Errors> {
[INFO] [stdout]    |                                          ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 24 |   fn evolve<'a>(&'a mut self, event: &'a dyn Event<T = T>) -> Result<(), Errors> {
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:24:27
[INFO] [stdout]    |
[INFO] [stdout] 24 |   fn evolve(self, event: &Event<T = T>) -> Result<A, Errors>{
[INFO] [stdout]    |                           ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 24 |   fn evolve(self, event: &dyn Event<T = T>) -> Result<A, Errors>{
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:16:27
[INFO] [stdout]    |
[INFO] [stdout] 16 |   fn evolve(self, event: &Event<T = T>) -> Result<A, Errors>;
[INFO] [stdout]    |                           ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 16 |   fn evolve(self, event: &dyn Event<T = T>) -> Result<A, Errors>;
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:16:42
[INFO] [stdout]    |
[INFO] [stdout] 16 |   fn evolve<'a>(&'a mut self, event: &'a Event<T = T>) -> Result<(), Errors>;
[INFO] [stdout]    |                                          ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 16 |   fn evolve<'a>(&'a mut self, event: &'a dyn Event<T = T>) -> Result<(), Errors>;
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:20:31
[INFO] [stdout]    |
[INFO] [stdout] 20 |   fn as_event<T>(self) -> Box<Event<T = T>+Send>;
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 20 |   fn as_event<T>(self) -> Box<dyn Event<T = T>+Send>;
[INFO] [stdout]    |                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:20:33
[INFO] [stdout]    |
[INFO] [stdout] 20 |   fn as_event<T,S>(self) -> Box<Event<T = T>+Send>;
[INFO] [stdout]    |                                 ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 20 |   fn as_event<T,S>(self) -> Box<dyn Event<T = T>+Send>;
[INFO] [stdout]    |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.16s
[INFO] running `Command { std: "docker" "inspect" "71e1d905722f343e2c90f81d67c86a04af94eed2fd9b4ad84452b0e375027297", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "71e1d905722f343e2c90f81d67c86a04af94eed2fd9b4ad84452b0e375027297", kill_on_drop: false }`
[INFO] [stdout] 71e1d905722f343e2c90f81d67c86a04af94eed2fd9b4ad84452b0e375027297
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+4987e9d4227139400384ab59296ffee3b0fb1183" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 17c31d50adc61972118e5d4bd525f3160aef140080319ea5b86a6b7fe47c25cb
[INFO] running `Command { std: "docker" "start" "-a" "17c31d50adc61972118e5d4bd525f3160aef140080319ea5b86a6b7fe47c25cb", kill_on_drop: false }`
[INFO] [stderr] warning: no edition set: defaulting to the 2015 edition while the latest is 2024
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:24:42
[INFO] [stdout]    |
[INFO] [stdout] 24 |   fn evolve<'a>(&'a mut self, event: &'a Event<T = T>) -> Result<(), Errors> {
[INFO] [stdout]    |                                          ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 24 |   fn evolve<'a>(&'a mut self, event: &'a dyn Event<T = T>) -> Result<(), Errors> {
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:24:27
[INFO] [stdout]    |
[INFO] [stdout] 24 |   fn evolve(self, event: &Event<T = T>) -> Result<A, Errors>{
[INFO] [stdout]    |                           ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 24 |   fn evolve(self, event: &dyn Event<T = T>) -> Result<A, Errors>{
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:16:27
[INFO] [stdout]    |
[INFO] [stdout] 16 |   fn evolve(self, event: &Event<T = T>) -> Result<A, Errors>;
[INFO] [stdout]    |                           ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 16 |   fn evolve(self, event: &dyn Event<T = T>) -> Result<A, Errors>;
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:16:42
[INFO] [stdout]    |
[INFO] [stdout] 16 |   fn evolve<'a>(&'a mut self, event: &'a Event<T = T>) -> Result<(), Errors>;
[INFO] [stdout]    |                                          ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 16 |   fn evolve<'a>(&'a mut self, event: &'a dyn Event<T = T>) -> Result<(), Errors>;
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:20:31
[INFO] [stdout]    |
[INFO] [stdout] 20 |   fn as_event<T>(self) -> Box<Event<T = T>+Send>;
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 20 |   fn as_event<T>(self) -> Box<dyn Event<T = T>+Send>;
[INFO] [stdout]    |                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:20:33
[INFO] [stdout]    |
[INFO] [stdout] 20 |   fn as_event<T,S>(self) -> Box<Event<T = T>+Send>;
[INFO] [stdout]    |                                 ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 20 |   fn as_event<T,S>(self) -> Box<dyn Event<T = T>+Send>;
[INFO] [stdout]    |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling strand v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:24:42
[INFO] [stdout]    |
[INFO] [stdout] 24 |   fn evolve<'a>(&'a mut self, event: &'a Event<T = T>) -> Result<(), Errors> {
[INFO] [stdout]    |                                          ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 24 |   fn evolve<'a>(&'a mut self, event: &'a dyn Event<T = T>) -> Result<(), Errors> {
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:24:27
[INFO] [stdout]    |
[INFO] [stdout] 24 |   fn evolve(self, event: &Event<T = T>) -> Result<A, Errors>{
[INFO] [stdout]    |                           ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 24 |   fn evolve(self, event: &dyn Event<T = T>) -> Result<A, Errors>{
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:16:42
[INFO] [stdout]    |
[INFO] [stdout] 16 |   fn evolve<'a>(&'a mut self, event: &'a Event<T = T>) -> Result<(), Errors>;
[INFO] [stdout]    |                                          ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 16 |   fn evolve<'a>(&'a mut self, event: &'a dyn Event<T = T>) -> Result<(), Errors>;
[INFO] [stdout]    |                                          +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:16:27
[INFO] [stdout]    |
[INFO] [stdout] 16 |   fn evolve(self, event: &Event<T = T>) -> Result<A, Errors>;
[INFO] [stdout]    |                           ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 16 |   fn evolve(self, event: &dyn Event<T = T>) -> Result<A, Errors>;
[INFO] [stdout]    |                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/immutable.rs:20:31
[INFO] [stdout]    |
[INFO] [stdout] 20 |   fn as_event<T>(self) -> Box<Event<T = T>+Send>;
[INFO] [stdout]    |                               ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 20 |   fn as_event<T>(self) -> Box<dyn Event<T = T>+Send>;
[INFO] [stdout]    |                               +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/mutable.rs:20:33
[INFO] [stdout]    |
[INFO] [stdout] 20 |   fn as_event<T,S>(self) -> Box<Event<T = T>+Send>;
[INFO] [stdout]    |                                 ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = warning: this is accepted in the current edition (Rust 2015) 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] 20 |   fn as_event<T,S>(self) -> Box<dyn Event<T = T>+Send>;
[INFO] [stdout]    |                                 +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.70s
[INFO] running `Command { std: "docker" "inspect" "17c31d50adc61972118e5d4bd525f3160aef140080319ea5b86a6b7fe47c25cb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "17c31d50adc61972118e5d4bd525f3160aef140080319ea5b86a6b7fe47c25cb", kill_on_drop: false }`
[INFO] [stdout] 17c31d50adc61972118e5d4bd525f3160aef140080319ea5b86a6b7fe47c25cb
