[INFO] fetching crate cl-format 0.1.2...
[INFO] checking cl-format-0.1.2 against master#e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682 for beta-170-4
[INFO] extracting crate cl-format 0.1.2 into /workspace/builds/worker-1-tc2/source
[INFO] validating manifest of crates.io crate cl-format 0.1.2 on toolchain e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cl-format 0.1.2
[INFO] finished tweaking crates.io crate cl-format 0.1.2
[INFO] tweaked toml for crates.io crate cl-format 0.1.2 written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] crate crates.io crate cl-format 0.1.2 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" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a37c9f63f84e9b972ec5b63cc9c29e0b10dd0a1f648a0a5d3a6b31b0e5b18a15
[INFO] running `Command { std: "docker" "start" "-a" "a37c9f63f84e9b972ec5b63cc9c29e0b10dd0a1f648a0a5d3a6b31b0e5b18a15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a37c9f63f84e9b972ec5b63cc9c29e0b10dd0a1f648a0a5d3a6b31b0e5b18a15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a37c9f63f84e9b972ec5b63cc9c29e0b10dd0a1f648a0a5d3a6b31b0e5b18a15", kill_on_drop: false }`
[INFO] [stdout] a37c9f63f84e9b972ec5b63cc9c29e0b10dd0a1f648a0a5d3a6b31b0e5b18a15
[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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+e6e4f7ed1589e03bc2f6c5931c1a72e7947e8682" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fcf6c62ea3790a962322260b9b37488f3c277c40bd053497810b14e50395992f
[INFO] running `Command { std: "docker" "start" "-a" "fcf6c62ea3790a962322260b9b37488f3c277c40bd053497810b14e50395992f", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.56
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]     Checking unicode-ident v1.0.8
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling syn v2.0.13
[INFO] [stderr]    Compiling cl-format-macros v0.1.0
[INFO] [stderr]     Checking cl-format v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/lib.rs:26:20
[INFO] [stdout]    |
[INFO] [stdout] 26 |                   fn format(&$s, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>>
[INFO] [stdout]    |                                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/tildes/reveal_impl.rs:6:1
[INFO] [stdout]    |
[INFO] [stdout] 6  | / multi_tilde_impl!(TildeKindDigit, [i32, i64, u32, u64, usize], self, {
[INFO] [stdout] 7  | |     Ok(Some(format!("{}", self)))
[INFO] [stdout] 8  | | });
[INFO] [stdout]    | |__- in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `multi_tilde_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/lib.rs:26:20
[INFO] [stdout]    |
[INFO] [stdout] 26 |                   fn format(&$s, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>>
[INFO] [stdout]    |                                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/tildes/reveal_impl.rs:27:1
[INFO] [stdout]    |
[INFO] [stdout] 27 | / multi_tilde_impl!(
[INFO] [stdout] 28 | |     TildeKindVa,
[INFO] [stdout] 29 | |     [f32, f64, char, i32, i64, usize, u32, u64, String],
[INFO] [stdout] 30 | |     self,
[INFO] [stdout] 31 | |     { Ok(Some(format!("{}", self))) }
[INFO] [stdout] 32 | | );
[INFO] [stdout]    | |_- in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `multi_tilde_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/tildes/reveal_impl.rs:35:22
[INFO] [stdout]    |
[INFO] [stdout] 35 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/tildes/reveal_impl.rs:45:22
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/tildes/reveal_impl.rs:51:22
[INFO] [stdout]    |
[INFO] [stdout] 51 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]    --> src/tildes/reveal_impl.rs:289:22
[INFO] [stdout]     |
[INFO] [stdout] 289 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]     |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]    --> src/tildes/reveal_impl.rs:295:22
[INFO] [stdout]     |
[INFO] [stdout] 295 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]     |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]    --> src/lib.rs:26:20
[INFO] [stdout]     |
[INFO] [stdout] 26  |                   fn format(&$s, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>>
[INFO] [stdout]     |                                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]     |
[INFO] [stdout]    ::: src/tildes/reveal_impl.rs:300:1
[INFO] [stdout]     |
[INFO] [stdout] 300 | / multi_tilde_impl!(
[INFO] [stdout] 301 | |     TildeKindStandard,
[INFO] [stdout] 302 | |     [f32, f64, i32, i64, usize, bool, u32, u64],
[INFO] [stdout] 303 | |     self,
[INFO] [stdout] 304 | |     { Ok(Some(format!("{}", self))) }
[INFO] [stdout] 305 | | );
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in the macro `multi_tilde_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `parse_vec` is never used
[INFO] [stdout]    --> src/tildes.rs:379:8
[INFO] [stdout]     |
[INFO] [stdout] 27  | impl Tilde {
[INFO] [stdout]     | ---------- associated function in this implementation
[INFO] [stdout] ...
[INFO] [stdout] 379 |     fn parse_vec(
[INFO] [stdout]     |        ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 9 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:172:13
[INFO] [stdout]     |
[INFO] [stdout] 172 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:189:13
[INFO] [stdout]     |
[INFO] [stdout] 189 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:244:13
[INFO] [stdout]     |
[INFO] [stdout] 244 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:269:13
[INFO] [stdout]     |
[INFO] [stdout] 269 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:320:13
[INFO] [stdout]     |
[INFO] [stdout] 320 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:321:13
[INFO] [stdout]     |
[INFO] [stdout] 321 |         let mut args: Vec<&dyn TildeAble> = vec![&1_i64];
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:331:13
[INFO] [stdout]     |
[INFO] [stdout] 331 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:332:13
[INFO] [stdout]     |
[INFO] [stdout] 332 |         let mut args: Vec<&dyn TildeAble> = vec![&2_i64, &2_i64];
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:342:13
[INFO] [stdout]     |
[INFO] [stdout] 342 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:343:13
[INFO] [stdout]     |
[INFO] [stdout] 343 |         let mut args: Vec<&dyn TildeAble> = vec![&3_i64, &3_i64, &3_i64];
[INFO] [stdout]     |             ----^^^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> tests/testcase1.rs:64:22
[INFO] [stdout]    |
[INFO] [stdout] 64 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> tests/testcase1.rs:70:22
[INFO] [stdout]    |
[INFO] [stdout] 70 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:359:13
[INFO] [stdout]     |
[INFO] [stdout] 359 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:374:13
[INFO] [stdout]     |
[INFO] [stdout] 374 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:384:13
[INFO] [stdout]     |
[INFO] [stdout] 384 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:403:13
[INFO] [stdout]     |
[INFO] [stdout] 403 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:418:13
[INFO] [stdout]     |
[INFO] [stdout] 418 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:427:13
[INFO] [stdout]     |
[INFO] [stdout] 427 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:439:13
[INFO] [stdout]     |
[INFO] [stdout] 439 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:451:13
[INFO] [stdout]     |
[INFO] [stdout] 451 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:463:13
[INFO] [stdout]     |
[INFO] [stdout] 463 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:475:13
[INFO] [stdout]     |
[INFO] [stdout] 475 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:488:13
[INFO] [stdout]     |
[INFO] [stdout] 488 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:495:13
[INFO] [stdout]     |
[INFO] [stdout] 495 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:511:13
[INFO] [stdout]     |
[INFO] [stdout] 511 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:522:13
[INFO] [stdout]     |
[INFO] [stdout] 522 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:542:13
[INFO] [stdout]     |
[INFO] [stdout] 542 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/control_str.rs:565:13
[INFO] [stdout]     |
[INFO] [stdout] 565 |         let mut cs = ControlStr::new(case)?;
[INFO] [stdout]     |             ----^^
[INFO] [stdout]     |             |
[INFO] [stdout]     |             help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/lib.rs:26:20
[INFO] [stdout]    |
[INFO] [stdout] 26 |                   fn format(&$s, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>>
[INFO] [stdout]    |                                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/tildes/reveal_impl.rs:6:1
[INFO] [stdout]    |
[INFO] [stdout] 6  | / multi_tilde_impl!(TildeKindDigit, [i32, i64, u32, u64, usize], self, {
[INFO] [stdout] 7  | |     Ok(Some(format!("{}", self)))
[INFO] [stdout] 8  | | });
[INFO] [stdout]    | |__- in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]    = note: this warning originates in the macro `multi_tilde_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/lib.rs:26:20
[INFO] [stdout]    |
[INFO] [stdout] 26 |                   fn format(&$s, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>>
[INFO] [stdout]    |                                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]    |
[INFO] [stdout]   ::: src/tildes/reveal_impl.rs:27:1
[INFO] [stdout]    |
[INFO] [stdout] 27 | / multi_tilde_impl!(
[INFO] [stdout] 28 | |     TildeKindVa,
[INFO] [stdout] 29 | |     [f32, f64, char, i32, i64, usize, u32, u64, String],
[INFO] [stdout] 30 | |     self,
[INFO] [stdout] 31 | |     { Ok(Some(format!("{}", self))) }
[INFO] [stdout] 32 | | );
[INFO] [stdout]    | |_- in this macro invocation
[INFO] [stdout]    |
[INFO] [stdout]    = note: this warning originates in the macro `multi_tilde_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/tildes/reveal_impl.rs:35:22
[INFO] [stdout]    |
[INFO] [stdout] 35 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/tildes/reveal_impl.rs:45:22
[INFO] [stdout]    |
[INFO] [stdout] 45 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]   --> src/tildes/reveal_impl.rs:51:22
[INFO] [stdout]    |
[INFO] [stdout] 51 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]    --> src/tildes/reveal_impl.rs:289:22
[INFO] [stdout]     |
[INFO] [stdout] 289 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]     |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]    --> src/tildes/reveal_impl.rs:295:22
[INFO] [stdout]     |
[INFO] [stdout] 295 |     fn format(&self, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>> {
[INFO] [stdout]     |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `tkind`
[INFO] [stdout]    --> src/lib.rs:26:20
[INFO] [stdout]     |
[INFO] [stdout] 26  |                   fn format(&$s, tkind: &TildeKind) -> Result<Option<String>, Box<dyn std::error::Error>>
[INFO] [stdout]     |                                  ^^^^^ help: if this is intentional, prefix it with an underscore: `_tkind`
[INFO] [stdout]     |
[INFO] [stdout]    ::: src/tildes/reveal_impl.rs:300:1
[INFO] [stdout]     |
[INFO] [stdout] 300 | / multi_tilde_impl!(
[INFO] [stdout] 301 | |     TildeKindStandard,
[INFO] [stdout] 302 | |     [f32, f64, i32, i64, usize, bool, u32, u64],
[INFO] [stdout] 303 | |     self,
[INFO] [stdout] 304 | |     { Ok(Some(format!("{}", self))) }
[INFO] [stdout] 305 | | );
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: this warning originates in the macro `multi_tilde_impl` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/control_str.rs:164:9
[INFO] [stdout]     |
[INFO] [stdout] 164 |         dbg!(c);
[INFO] [stdout]     |         ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this warning originates in the macro `dbg` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 35 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.95s
[INFO] running `Command { std: "docker" "inspect" "fcf6c62ea3790a962322260b9b37488f3c277c40bd053497810b14e50395992f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fcf6c62ea3790a962322260b9b37488f3c277c40bd053497810b14e50395992f", kill_on_drop: false }`
[INFO] [stdout] fcf6c62ea3790a962322260b9b37488f3c277c40bd053497810b14e50395992f
