[INFO] cloning repository https://github.com/Mr-Helpful/scrabble.rs
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Mr-Helpful/scrabble.rs" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMr-Helpful%2Fscrabble.rs", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMr-Helpful%2Fscrabble.rs'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cb9662b2f6fb74bec5e1c6eed9181f118ed2fd63
[INFO] checking Mr-Helpful/scrabble.rs against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMr-Helpful%2Fscrabble.rs" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/Mr-Helpful/scrabble.rs
[INFO] finished tweaking git repo https://github.com/Mr-Helpful/scrabble.rs
[INFO] tweaked toml for git repo https://github.com/Mr-Helpful/scrabble.rs written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/Mr-Helpful/scrabble.rs on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/Mr-Helpful/scrabble.rs 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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c0312ab1be62fb63f1ce075cb65df259df1f7e4062111bdd190c83a806980868
[INFO] running `Command { std: "docker" "start" "-a" "c0312ab1be62fb63f1ce075cb65df259df1f7e4062111bdd190c83a806980868", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c0312ab1be62fb63f1ce075cb65df259df1f7e4062111bdd190c83a806980868", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c0312ab1be62fb63f1ce075cb65df259df1f7e4062111bdd190c83a806980868", kill_on_drop: false }`
[INFO] [stdout] c0312ab1be62fb63f1ce075cb65df259df1f7e4062111bdd190c83a806980868
[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 -Dunmustuse_in_always_ok" "-e" "RUSTDOCFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] af5fe6abd16988c1f237126ab5313bcdcf1bf1139ed875b3ba06cc035f874fe7
[INFO] running `Command { std: "docker" "start" "-a" "af5fe6abd16988c1f237126ab5313bcdcf1bf1139ed875b3ba06cc035f874fe7", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.137
[INFO] [stderr]     Checking memchr v2.6.2
[INFO] [stderr]     Checking trees v0.4.2
[INFO] [stderr]     Checking weak-table v0.3.2
[INFO] [stderr]     Checking allwords v0.1.2
[INFO] [stderr]     Checking nom v7.1.3
[INFO] [stderr]     Checking getrandom v0.2.8
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking scrabble v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/letter/unparse.rs:28:16
[INFO] [stdout]    |
[INFO] [stdout] 28 |   TooManyChars(usize),
[INFO] [stdout]    |   ------------ ^^^^^
[INFO] [stdout]    |   |
[INFO] [stdout]    |   field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ErrorKind` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 28 -   TooManyChars(usize),
[INFO] [stdout] 28 +   TooManyChars(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/letter/unparse.rs:29:15
[INFO] [stdout]    |
[INFO] [stdout] 29 |   TooFewChars(usize),
[INFO] [stdout]    |   ----------- ^^^^^
[INFO] [stdout]    |   |
[INFO] [stdout]    |   field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ErrorKind` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 29 -   TooFewChars(usize),
[INFO] [stdout] 29 +   TooFewChars(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `StringIterator` is never constructed
[INFO] [stdout]    --> src/trie/node_trait.rs:255:12
[INFO] [stdout]     |
[INFO] [stdout] 255 | pub struct StringIterator<'a, T: TrieNode> {
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: call to `.borrow()` on a reference in this situation does nothing
[INFO] [stdout]   --> src/dawg/ptrs.rs:68:20
[INFO] [stdout]    |
[INFO] [stdout] 68 |     self.0.as_ref().borrow()
[INFO] [stdout]    |                    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: the type `Node` does not implement `Borrow`, so calling `borrow` on `&Node` copies the reference, which does not do anything and can be removed
[INFO] [stdout]    = note: `#[warn(noop_method_call)]` on by default
[INFO] [stdout] help: remove this redundant call
[INFO] [stdout]    |
[INFO] [stdout] 68 -     self.0.as_ref().borrow()
[INFO] [stdout] 68 +     self.0.as_ref()
[INFO] [stdout]    |
[INFO] [stdout] help: if you meant to clone `Node`, implement `Clone` for it
[INFO] [stdout]    |
[INFO] [stdout] 59 + #[derive(Clone)]
[INFO] [stdout] 60 | pub struct Node {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: call to `.borrow()` on a reference in this situation does nothing
[INFO] [stdout]   --> src/dawg/ptrs.rs:74:20
[INFO] [stdout]    |
[INFO] [stdout] 74 |     self.0.as_ref().borrow()
[INFO] [stdout]    |                    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: the type `Node` does not implement `Borrow`, so calling `borrow` on `&Node` copies the reference, which does not do anything and can be removed
[INFO] [stdout] help: remove this redundant call
[INFO] [stdout]    |
[INFO] [stdout] 74 -     self.0.as_ref().borrow()
[INFO] [stdout] 74 +     self.0.as_ref()
[INFO] [stdout]    |
[INFO] [stdout] help: if you meant to clone `Node`, implement `Clone` for it
[INFO] [stdout]    |
[INFO] [stdout] 59 + #[derive(Clone)]
[INFO] [stdout] 60 | pub struct Node {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:55:82
[INFO] [stdout]    |
[INFO] [stdout] 55 |   fn unparse_char_pair(&(start, end): &(char, char)) -> Result<String, Infallible> {
[INFO] [stdout]    |  __________________________________________________________________________________^
[INFO] [stdout] 56 | |   if start == end {
[INFO] [stdout] 57 | |     Ok(start.into())
[INFO] [stdout] 58 | |   } else {
[INFO] [stdout] ...  |
[INFO] [stdout] 61 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:56:3
[INFO] [stdout]    |
[INFO] [stdout] 56 | /   if start == end {
[INFO] [stdout] 57 | |     Ok(start.into())
[INFO] [stdout] 58 | |   } else {
[INFO] [stdout] 59 | |     Ok(format!("{}-{}", start, end))
[INFO] [stdout] 60 | |   }
[INFO] [stdout]    | |___^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:56:19
[INFO] [stdout]    |
[INFO] [stdout] 56 |     if start == end {
[INFO] [stdout]    |  ___________________^
[INFO] [stdout] 57 | |     Ok(start.into())
[INFO] [stdout] 58 | |   } else {
[INFO] [stdout]    | |___^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 57 |     Ok(start.into())
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:58:10
[INFO] [stdout]    |
[INFO] [stdout] 58 |     } else {
[INFO] [stdout]    |  __________^
[INFO] [stdout] 59 | |     Ok(format!("{}-{}", start, end))
[INFO] [stdout] 60 | |   }
[INFO] [stdout]    | |___^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:59:5
[INFO] [stdout]    |
[INFO] [stdout] 59 |     Ok(format!("{}-{}", start, end))
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:63:72
[INFO] [stdout]    |
[INFO] [stdout] 63 |   fn unparse_group_letter(letter: &Letter) -> Result<String, Infallible> {
[INFO] [stdout]    |  ________________________________________________________________________^
[INFO] [stdout] 64 | |   let ranges = combine_into_ranges(letter.indices());
[INFO] [stdout] 65 | |   let ranges_string = ranges
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout] 68 | |   Ok(format!("[{}]", ranges_string))
[INFO] [stdout] 69 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: ControlFlow<Result<Infallible, Infallible>, String>
[INFO] [stdout]   --> src/letter/unparse.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     let ranges_string = ranges
[INFO] [stdout]    |  _______________________^
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout]    | |____________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     let ranges_string = ranges
[INFO] [stdout]    |  _______________________^
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout]    | |___________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:66:19
[INFO] [stdout]    |
[INFO] [stdout] 66 |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     let ranges_string = ranges
[INFO] [stdout]    |  _______________________^
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout]    | |____________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:68:3
[INFO] [stdout]    |
[INFO] [stdout] 68 |   Ok(format!("[{}]", ranges_string))
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:71:77
[INFO] [stdout]    |
[INFO] [stdout] 71 |   pub(crate) fn unparse_letter(letter: &Letter) -> Result<String, Infallible> {
[INFO] [stdout]    |  _____________________________________________________________________________^
[INFO] [stdout] 72 | |   unparse_dot_letter(letter)
[INFO] [stdout] 73 | |     .or_else(|_| unparse_char_letter(letter))
[INFO] [stdout] 74 | |     .or_else(|_| unparse_group_letter(letter))
[INFO] [stdout] 75 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:72:3
[INFO] [stdout]    |
[INFO] [stdout] 72 | /   unparse_dot_letter(letter)
[INFO] [stdout] 73 | |     .or_else(|_| unparse_char_letter(letter))
[INFO] [stdout] 74 | |     .or_else(|_| unparse_group_letter(letter))
[INFO] [stdout]    | |______________________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:74:18
[INFO] [stdout]    |
[INFO] [stdout] 74 |     .or_else(|_| unparse_group_letter(letter))
[INFO] [stdout]    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:79:21
[INFO] [stdout]    |
[INFO] [stdout] 79 |     write!(f, "{}", unparse_letter(self).unwrap())
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: eliding a lifetime that's named elsewhere is confusing
[INFO] [stdout]    --> src/trie/node_trait.rs:223:64
[INFO] [stdout]     |
[INFO] [stdout] 223 |   fn extract<'a>(&'a self, other: &'a Self) -> ExtractIterator<'_, Self> {
[INFO] [stdout]     |                   --               --                          ^^ the same lifetime is elided here
[INFO] [stdout]     |                   |                |
[INFO] [stdout]     |                   |                the lifetime is named here
[INFO] [stdout]     |                   the lifetime is named here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: consistently use `'a`
[INFO] [stdout]     |
[INFO] [stdout] 223 -   fn extract<'a>(&'a self, other: &'a Self) -> ExtractIterator<'_, Self> {
[INFO] [stdout] 223 +   fn extract<'a>(&'a self, other: &'a Self) -> ExtractIterator<'a, Self> {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/word/unparse.rs:5:60
[INFO] [stdout]    |
[INFO] [stdout]  5 |   fn unparse_word(word: &Word) -> Result<String, Infallible> {
[INFO] [stdout]    |  ____________________________________________________________^
[INFO] [stdout]  6 | |   word
[INFO] [stdout]  7 | |     .letters()
[INFO] [stdout]  8 | |     .map(unparse_letter)
[INFO] [stdout]  9 | |     .collect::<Result<String, _>>()
[INFO] [stdout] 10 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]  --> src/word/unparse.rs:6:3
[INFO] [stdout]   |
[INFO] [stdout] 6 | /   word
[INFO] [stdout] 7 | |     .letters()
[INFO] [stdout] 8 | |     .map(unparse_letter)
[INFO] [stdout] 9 | |     .collect::<Result<String, _>>()
[INFO] [stdout]   | |___________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/word/unparse.rs:14:21
[INFO] [stdout]    |
[INFO] [stdout] 14 |     write!(f, "{}", unparse_word(self).unwrap())
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `scrabble` (lib) due to 19 previous errors; 6 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/letter/unparse.rs:28:16
[INFO] [stdout]    |
[INFO] [stdout] 28 |   TooManyChars(usize),
[INFO] [stdout]    |   ------------ ^^^^^
[INFO] [stdout]    |   |
[INFO] [stdout]    |   field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ErrorKind` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 28 -   TooManyChars(usize),
[INFO] [stdout] 28 +   TooManyChars(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/letter/unparse.rs:29:15
[INFO] [stdout]    |
[INFO] [stdout] 29 |   TooFewChars(usize),
[INFO] [stdout]    |   ----------- ^^^^^
[INFO] [stdout]    |   |
[INFO] [stdout]    |   field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `ErrorKind` has derived impls for the traits `Clone` and `Debug`, but these are intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 29 -   TooFewChars(usize),
[INFO] [stdout] 29 +   TooFewChars(()),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `StringIterator` is never constructed
[INFO] [stdout]    --> src/trie/node_trait.rs:255:12
[INFO] [stdout]     |
[INFO] [stdout] 255 | pub struct StringIterator<'a, T: TrieNode> {
[INFO] [stdout]     |            ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: call to `.borrow()` on a reference in this situation does nothing
[INFO] [stdout]   --> src/dawg/ptrs.rs:68:20
[INFO] [stdout]    |
[INFO] [stdout] 68 |     self.0.as_ref().borrow()
[INFO] [stdout]    |                    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: the type `Node` does not implement `Borrow`, so calling `borrow` on `&Node` copies the reference, which does not do anything and can be removed
[INFO] [stdout]    = note: `#[warn(noop_method_call)]` on by default
[INFO] [stdout] help: remove this redundant call
[INFO] [stdout]    |
[INFO] [stdout] 68 -     self.0.as_ref().borrow()
[INFO] [stdout] 68 +     self.0.as_ref()
[INFO] [stdout]    |
[INFO] [stdout] help: if you meant to clone `Node`, implement `Clone` for it
[INFO] [stdout]    |
[INFO] [stdout] 59 + #[derive(Clone)]
[INFO] [stdout] 60 | pub struct Node {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: call to `.borrow()` on a reference in this situation does nothing
[INFO] [stdout]   --> src/dawg/ptrs.rs:74:20
[INFO] [stdout]    |
[INFO] [stdout] 74 |     self.0.as_ref().borrow()
[INFO] [stdout]    |                    ^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: the type `Node` does not implement `Borrow`, so calling `borrow` on `&Node` copies the reference, which does not do anything and can be removed
[INFO] [stdout] help: remove this redundant call
[INFO] [stdout]    |
[INFO] [stdout] 74 -     self.0.as_ref().borrow()
[INFO] [stdout] 74 +     self.0.as_ref()
[INFO] [stdout]    |
[INFO] [stdout] help: if you meant to clone `Node`, implement `Clone` for it
[INFO] [stdout]    |
[INFO] [stdout] 59 + #[derive(Clone)]
[INFO] [stdout] 60 | pub struct Node {
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:55:82
[INFO] [stdout]    |
[INFO] [stdout] 55 |   fn unparse_char_pair(&(start, end): &(char, char)) -> Result<String, Infallible> {
[INFO] [stdout]    |  __________________________________________________________________________________^
[INFO] [stdout] 56 | |   if start == end {
[INFO] [stdout] 57 | |     Ok(start.into())
[INFO] [stdout] 58 | |   } else {
[INFO] [stdout] ...  |
[INFO] [stdout] 61 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:56:3
[INFO] [stdout]    |
[INFO] [stdout] 56 | /   if start == end {
[INFO] [stdout] 57 | |     Ok(start.into())
[INFO] [stdout] 58 | |   } else {
[INFO] [stdout] 59 | |     Ok(format!("{}-{}", start, end))
[INFO] [stdout] 60 | |   }
[INFO] [stdout]    | |___^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:56:19
[INFO] [stdout]    |
[INFO] [stdout] 56 |     if start == end {
[INFO] [stdout]    |  ___________________^
[INFO] [stdout] 57 | |     Ok(start.into())
[INFO] [stdout] 58 | |   } else {
[INFO] [stdout]    | |___^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:57:5
[INFO] [stdout]    |
[INFO] [stdout] 57 |     Ok(start.into())
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:58:10
[INFO] [stdout]    |
[INFO] [stdout] 58 |     } else {
[INFO] [stdout]    |  __________^
[INFO] [stdout] 59 | |     Ok(format!("{}-{}", start, end))
[INFO] [stdout] 60 | |   }
[INFO] [stdout]    | |___^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:59:5
[INFO] [stdout]    |
[INFO] [stdout] 59 |     Ok(format!("{}-{}", start, end))
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:63:72
[INFO] [stdout]    |
[INFO] [stdout] 63 |   fn unparse_group_letter(letter: &Letter) -> Result<String, Infallible> {
[INFO] [stdout]    |  ________________________________________________________________________^
[INFO] [stdout] 64 | |   let ranges = combine_into_ranges(letter.indices());
[INFO] [stdout] 65 | |   let ranges_string = ranges
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout] 68 | |   Ok(format!("[{}]", ranges_string))
[INFO] [stdout] 69 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: ControlFlow<Result<Infallible, Infallible>, String>
[INFO] [stdout]   --> src/letter/unparse.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     let ranges_string = ranges
[INFO] [stdout]    |  _______________________^
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout]    | |____________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     let ranges_string = ranges
[INFO] [stdout]    |  _______________________^
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout]    | |___________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:66:19
[INFO] [stdout]    |
[INFO] [stdout] 66 |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout]    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:65:23
[INFO] [stdout]    |
[INFO] [stdout] 65 |     let ranges_string = ranges
[INFO] [stdout]    |  _______________________^
[INFO] [stdout] 66 | |     .map(|(s, e)| unparse_char_pair(&(from_index(s), from_index(e))))
[INFO] [stdout] 67 | |     .collect::<Result<String, _>>()?;
[INFO] [stdout]    | |____________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:68:3
[INFO] [stdout]    |
[INFO] [stdout] 68 |   Ok(format!("[{}]", ranges_string))
[INFO] [stdout]    |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:71:77
[INFO] [stdout]    |
[INFO] [stdout] 71 |   pub(crate) fn unparse_letter(letter: &Letter) -> Result<String, Infallible> {
[INFO] [stdout]    |  _____________________________________________________________________________^
[INFO] [stdout] 72 | |   unparse_dot_letter(letter)
[INFO] [stdout] 73 | |     .or_else(|_| unparse_char_letter(letter))
[INFO] [stdout] 74 | |     .or_else(|_| unparse_group_letter(letter))
[INFO] [stdout] 75 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:72:3
[INFO] [stdout]    |
[INFO] [stdout] 72 | /   unparse_dot_letter(letter)
[INFO] [stdout] 73 | |     .or_else(|_| unparse_char_letter(letter))
[INFO] [stdout] 74 | |     .or_else(|_| unparse_group_letter(letter))
[INFO] [stdout]    | |______________________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:74:18
[INFO] [stdout]    |
[INFO] [stdout] 74 |     .or_else(|_| unparse_group_letter(letter))
[INFO] [stdout]    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/letter/unparse.rs:79:21
[INFO] [stdout]    |
[INFO] [stdout] 79 |     write!(f, "{}", unparse_letter(self).unwrap())
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: eliding a lifetime that's named elsewhere is confusing
[INFO] [stdout]    --> src/trie/node_trait.rs:223:64
[INFO] [stdout]     |
[INFO] [stdout] 223 |   fn extract<'a>(&'a self, other: &'a Self) -> ExtractIterator<'_, Self> {
[INFO] [stdout]     |                   --               --                          ^^ the same lifetime is elided here
[INFO] [stdout]     |                   |                |
[INFO] [stdout]     |                   |                the lifetime is named here
[INFO] [stdout]     |                   the lifetime is named here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: consistently use `'a`
[INFO] [stdout]     |
[INFO] [stdout] 223 -   fn extract<'a>(&'a self, other: &'a Self) -> ExtractIterator<'_, Self> {
[INFO] [stdout] 223 +   fn extract<'a>(&'a self, other: &'a Self) -> ExtractIterator<'a, Self> {
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/word/unparse.rs:5:60
[INFO] [stdout]    |
[INFO] [stdout]  5 |   fn unparse_word(word: &Word) -> Result<String, Infallible> {
[INFO] [stdout]    |  ____________________________________________________________^
[INFO] [stdout]  6 | |   word
[INFO] [stdout]  7 | |     .letters()
[INFO] [stdout]  8 | |     .map(unparse_letter)
[INFO] [stdout]  9 | |     .collect::<Result<String, _>>()
[INFO] [stdout] 10 | | }
[INFO] [stdout]    | |_^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]  --> src/word/unparse.rs:6:3
[INFO] [stdout]   |
[INFO] [stdout] 6 | /   word
[INFO] [stdout] 7 | |     .letters()
[INFO] [stdout] 8 | |     .map(unparse_letter)
[INFO] [stdout] 9 | |     .collect::<Result<String, _>>()
[INFO] [stdout]   | |___________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: Result<String, Infallible>
[INFO] [stdout]   --> src/word/unparse.rs:14:21
[INFO] [stdout]    |
[INFO] [stdout] 14 |     write!(f, "{}", unparse_word(self).unwrap())
[INFO] [stdout]    |                     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `scrabble` (lib test) due to 19 previous errors; 6 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "af5fe6abd16988c1f237126ab5313bcdcf1bf1139ed875b3ba06cc035f874fe7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "af5fe6abd16988c1f237126ab5313bcdcf1bf1139ed875b3ba06cc035f874fe7", kill_on_drop: false }`
[INFO] [stdout] af5fe6abd16988c1f237126ab5313bcdcf1bf1139ed875b3ba06cc035f874fe7