[INFO] fetching crate ruSTLa 0.38.0...
[INFO] checking ruSTLa-0.38.0 against master#385fa9d845dd326c6bbfd58c22244215e431948a for never-type-fallback-to-never
[INFO] extracting crate ruSTLa 0.38.0 into /workspace/builds/worker-3-tc1/source
[INFO] validating manifest of crates.io crate ruSTLa 0.38.0 on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ruSTLa 0.38.0
[INFO] finished tweaking crates.io crate ruSTLa 0.38.0
[INFO] tweaked toml for crates.io crate ruSTLa 0.38.0 written to /workspace/builds/worker-3-tc1/source/Cargo.toml
[INFO] crate crates.io crate ruSTLa 0.38.0 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded regex-syntax v0.6.21
[INFO] [stderr]   Downloaded regex v1.4.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2af6cbacd0544c9e152cdff25d9c8500daac271c2e1715ef4831fe9cd5dc9629
[INFO] running `Command { std: "docker" "start" "-a" "2af6cbacd0544c9e152cdff25d9c8500daac271c2e1715ef4831fe9cd5dc9629", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2af6cbacd0544c9e152cdff25d9c8500daac271c2e1715ef4831fe9cd5dc9629", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2af6cbacd0544c9e152cdff25d9c8500daac271c2e1715ef4831fe9cd5dc9629", kill_on_drop: false }`
[INFO] [stdout] 2af6cbacd0544c9e152cdff25d9c8500daac271c2e1715ef4831fe9cd5dc9629
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 05ef4c31c0956f0f95646daeb011ea4eae4cc3cf01b7c42b9ec22b90ecc5f8e6
[INFO] running `Command { std: "docker" "start" "-a" "05ef4c31c0956f0f95646daeb011ea4eae4cc3cf01b7c42b9ec22b90ecc5f8e6", kill_on_drop: false }`
[INFO] [stderr]    Compiling ruSTLa v0.38.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking regex-syntax v0.6.21
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]     Checking aho-corasick v0.7.10
[INFO] [stderr]     Checking regex v1.4.2
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/block_quote.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/body.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `regex_patterns` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/transitions.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `regex_patterns` is already imported here
[INFO] [stdout] 8 | use crate::parser::regex_patterns;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/block_quote.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/body.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `regex_patterns` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/transitions.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `regex_patterns` is already imported here
[INFO] [stdout] 8 | use crate::parser::regex_patterns;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `rustla` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use rustla;
[INFO] [stdout]   |     ^^^^^^ the item `rustla` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `rustla` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use rustla;
[INFO] [stdout]   |     ^^^^^^ the item `rustla` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]    --> src/parser/tests/test_unknown_directives.rs:108:55
[INFO] [stdout]     |
[INFO] [stdout] 108 |             assert!(options.get("option4").is_none(), true);
[INFO] [stdout]     |                                                       ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this usage of `assert!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]     = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: add a "{}" format string to `Display` the message
[INFO] [stdout]     |
[INFO] [stdout] 108 |             assert!(options.get("option4").is_none(), "{}", true);
[INFO] [stdout]     |                                                       +++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 5.96s
[INFO] running `Command { std: "docker" "inspect" "05ef4c31c0956f0f95646daeb011ea4eae4cc3cf01b7c42b9ec22b90ecc5f8e6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "05ef4c31c0956f0f95646daeb011ea4eae4cc3cf01b7c42b9ec22b90ecc5f8e6", kill_on_drop: false }`
[INFO] [stdout] 05ef4c31c0956f0f95646daeb011ea4eae4cc3cf01b7c42b9ec22b90ecc5f8e6
[INFO] checking ruSTLa-0.38.0 against try#2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2 for never-type-fallback-to-never
[INFO] extracting crate ruSTLa 0.38.0 into /workspace/builds/worker-3-tc2/source
[INFO] validating manifest of crates.io crate ruSTLa 0.38.0 on toolchain 2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ruSTLa 0.38.0
[INFO] finished tweaking crates.io crate ruSTLa 0.38.0
[INFO] tweaked toml for crates.io crate ruSTLa 0.38.0 written to /workspace/builds/worker-3-tc2/source/Cargo.toml
[INFO] crate crates.io crate ruSTLa 0.38.0 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" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cf94cc62e73a68f1b9564019aa57b6480b7eefb512eb69f4b5122e8eb560d834
[INFO] running `Command { std: "docker" "start" "-a" "cf94cc62e73a68f1b9564019aa57b6480b7eefb512eb69f4b5122e8eb560d834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cf94cc62e73a68f1b9564019aa57b6480b7eefb512eb69f4b5122e8eb560d834", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cf94cc62e73a68f1b9564019aa57b6480b7eefb512eb69f4b5122e8eb560d834", kill_on_drop: false }`
[INFO] [stdout] cf94cc62e73a68f1b9564019aa57b6480b7eefb512eb69f4b5122e8eb560d834
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+2d84f2737f3bd9ebfcb07f75aa198d6cf7c715d2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fe1db5b4884ea4c417f35a592551acda4e2f34aa102f297680304867d688169d
[INFO] running `Command { std: "docker" "start" "-a" "fe1db5b4884ea4c417f35a592551acda4e2f34aa102f297680304867d688169d", kill_on_drop: false }`
[INFO] [stderr]     Checking regex-syntax v0.6.21
[INFO] [stderr]    Compiling ruSTLa v0.38.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking thread_local v1.0.1
[INFO] [stderr]     Checking aho-corasick v0.7.10
[INFO] [stderr]     Checking regex v1.4.2
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/block_quote.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/body.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `regex_patterns` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/transitions.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `regex_patterns` is already imported here
[INFO] [stdout] 8 | use crate::parser::regex_patterns;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/block_quote.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IndentedBlockResult` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/body.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `IndentedBlockResult` is already imported here
[INFO] [stdout] 8 | use crate::parser::types_and_aliases::IndentedBlockResult;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `regex_patterns` is imported redundantly
[INFO] [stdout]  --> src/parser/state_machine/transitions.rs:8:5
[INFO] [stdout]   |
[INFO] [stdout] 7 | use super::*;
[INFO] [stdout]   |     -------- the item `regex_patterns` is already imported here
[INFO] [stdout] 8 | use crate::parser::regex_patterns;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `rustla` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use rustla;
[INFO] [stdout]   |     ^^^^^^ the item `rustla` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `rustla` is imported redundantly
[INFO] [stdout]  --> src/main.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 | use rustla;
[INFO] [stdout]   |     ^^^^^^ the item `rustla` is already defined by prelude
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]    --> src/parser/tests/test_unknown_directives.rs:108:55
[INFO] [stdout]     |
[INFO] [stdout] 108 |             assert!(options.get("option4").is_none(), true);
[INFO] [stdout]     |                                                       ^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this usage of `assert!()` is deprecated; it will be a hard error in Rust 2021
[INFO] [stdout]     = note: for more information, see <https://doc.rust-lang.org/nightly/edition-guide/rust-2021/panic-macro-consistency.html>
[INFO] [stdout]     = note: `#[warn(non_fmt_panics)]` on by default
[INFO] [stdout] help: add a "{}" format string to `Display` the message
[INFO] [stdout]     |
[INFO] [stdout] 108 |             assert!(options.get("option4").is_none(), "{}", true);
[INFO] [stdout]     |                                                       +++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 6.11s
[INFO] running `Command { std: "docker" "inspect" "fe1db5b4884ea4c417f35a592551acda4e2f34aa102f297680304867d688169d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fe1db5b4884ea4c417f35a592551acda4e2f34aa102f297680304867d688169d", kill_on_drop: false }`
[INFO] [stdout] fe1db5b4884ea4c417f35a592551acda4e2f34aa102f297680304867d688169d