[INFO] crate randomforests 0.1.0 is already in cache
[INFO] extracting crate randomforests 0.1.0 into work/ex/clippy-test-run/sources/stable/reg/randomforests/0.1.0
[INFO] extracting crate randomforests 0.1.0 into work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/randomforests/0.1.0
[INFO] validating manifest of randomforests-0.1.0 on toolchain stable
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of randomforests-0.1.0 on toolchain stable+rustflags=-Dclippy::into_iter_on_array
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing randomforests-0.1.0
[INFO] finished frobbing randomforests-0.1.0
[INFO] frobbed toml for randomforests-0.1.0 written to work/ex/clippy-test-run/sources/stable/reg/randomforests/0.1.0/Cargo.toml
[INFO] started frobbing randomforests-0.1.0
[INFO] finished frobbing randomforests-0.1.0
[INFO] frobbed toml for randomforests-0.1.0 written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/randomforests/0.1.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+stable" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] linting randomforests-0.1.0 against stable for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-2/stable:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable/reg/randomforests/0.1.0:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+stable" "clippy" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 74143087a5e324c2369a13745004e9afd7da18f429ce4fc800424d5969e70d93
[INFO] running `"docker" "start" "-a" "74143087a5e324c2369a13745004e9afd7da18f429ce4fc800424d5969e70d93"`
[INFO] [stderr]     Checking randomforests v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:233:13
[INFO] [stderr]     |
[INFO] [stderr] 233 |             print!("Item: {:?}\n", item);
[INFO] [stderr]     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::print_with_newline)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:236:17
[INFO] [stderr]     |
[INFO] [stderr] 236 |                 print!("\tAttribute: {:?}\n", attribute);
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:259:17
[INFO] [stderr]     |
[INFO] [stderr] 259 | /                 print!(
[INFO] [stderr] 260 | |                     "\tE(t) = {:?}, E(f) = {:?}\n",
[INFO] [stderr] 261 | |                     _true_branch_entropy, _false_branch_entropy
[INFO] [stderr] 262 | |                 );
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:643:9
[INFO] [stderr]     |
[INFO] [stderr] 643 |         print!("decision: {:?}\n", t.decision);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:696:9
[INFO] [stderr]     |
[INFO] [stderr] 696 |         print!("decision: {:?}\n", t.decision);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:807:9
[INFO] [stderr]     |
[INFO] [stderr] 807 |         print!("answer = {:?}\n", answer);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:233:13
[INFO] [stderr]     |
[INFO] [stderr] 233 |             print!("Item: {:?}\n", item);
[INFO] [stderr]     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::print_with_newline)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:236:17
[INFO] [stderr]     |
[INFO] [stderr] 236 |                 print!("\tAttribute: {:?}\n", attribute);
[INFO] [stderr]     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:259:17
[INFO] [stderr]     |
[INFO] [stderr] 259 | /                 print!(
[INFO] [stderr] 260 | |                     "\tE(t) = {:?}, E(f) = {:?}\n",
[INFO] [stderr] 261 | |                     _true_branch_entropy, _false_branch_entropy
[INFO] [stderr] 262 | |                 );
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:643:9
[INFO] [stderr]     |
[INFO] [stderr] 643 |         print!("decision: {:?}\n", t.decision);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:696:9
[INFO] [stderr]     |
[INFO] [stderr] 696 |         print!("decision: {:?}\n", t.decision);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: using `print!()` with a format string that ends in a single newline, consider using `println!()` instead
[INFO] [stderr]    --> src/lib.rs:807:9
[INFO] [stderr]     |
[INFO] [stderr] 807 |         print!("answer = {:?}\n", answer);
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#print_with_newline
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/lib.rs:20:9
[INFO] [stderr]    |
[INFO] [stderr] 20 | /         return TreeConfig {
[INFO] [stderr] 21 | |             decision: "category".to_string(),
[INFO] [stderr] 22 | |             max_depth: 70,
[INFO] [stderr] 23 | |             min_count: 1,
[INFO] [stderr] 24 | |             entropy_threshold: 0.01,
[INFO] [stderr] 25 | |         };
[INFO] [stderr]    | |__________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]    |
[INFO] [stderr] 20 |         TreeConfig {
[INFO] [stderr] 21 |             decision: "category".to_string(),
[INFO] [stderr] 22 |             max_depth: 70,
[INFO] [stderr] 23 |             min_count: 1,
[INFO] [stderr] 24 |             entropy_threshold: 0.01,
[INFO] [stderr] 25 |         }
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     return counter;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^ help: remove `return` as shown: `counter`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:134:5
[INFO] [stderr]     |
[INFO] [stderr] 134 |     return most_frequent_value;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `most_frequent_value`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:155:5
[INFO] [stderr]     |
[INFO] [stderr] 155 | /     return Split {
[INFO] [stderr] 156 | |         gain: 0.0,
[INFO] [stderr] 157 | |         true_branch,
[INFO] [stderr] 158 | |         false_branch,
[INFO] [stderr] ...   |
[INFO] [stderr] 162 | |         },
[INFO] [stderr] 163 | |     };
[INFO] [stderr]     | |______^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]     |
[INFO] [stderr] 155 |     Split {
[INFO] [stderr] 156 |         gain: 0.0,
[INFO] [stderr] 157 |         true_branch,
[INFO] [stderr] 158 |         false_branch,
[INFO] [stderr] 159 |         attribute: "category".to_string(),
[INFO] [stderr] 160 |         pivot: Value {
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:174:5
[INFO] [stderr]     |
[INFO] [stderr] 174 |     return entropy;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^ help: remove `return` as shown: `entropy`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:300:13
[INFO] [stderr]     |
[INFO] [stderr] 300 |             return tree;
[INFO] [stderr]     |             ^^^^^^^^^^^^ help: remove `return` as shown: `tree`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:302:13
[INFO] [stderr]     |
[INFO] [stderr] 302 | /             return Some(Box::new(DecisionTree {
[INFO] [stderr] 303 | |                 decision: value_frequency(&config.decision, &data),
[INFO] [stderr] 304 | |                 true_branch: None,
[INFO] [stderr] 305 | |                 false_branch: None,
[INFO] [stderr] 306 | |                 attribute: None,
[INFO] [stderr] 307 | |                 pivot: None,
[INFO] [stderr] 308 | |             }));
[INFO] [stderr]     | |________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]     |
[INFO] [stderr] 302 |             Some(Box::new(DecisionTree {
[INFO] [stderr] 303 |                 decision: value_frequency(&config.decision, &data),
[INFO] [stderr] 304 |                 true_branch: None,
[INFO] [stderr] 305 |                 false_branch: None,
[INFO] [stderr] 306 |                 attribute: None,
[INFO] [stderr] 307 |                 pivot: None,
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:343:5
[INFO] [stderr]     |
[INFO] [stderr] 343 |     return shuffled;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^ help: remove `return` as shown: `shuffled`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:364:9
[INFO] [stderr]     |
[INFO] [stderr] 364 | /         return RandomForest {
[INFO] [stderr] 365 | |             trees
[INFO] [stderr] 366 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]     |
[INFO] [stderr] 364 |         RandomForest {
[INFO] [stderr] 365 |             trees
[INFO] [stderr] 366 |         }
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:382:9
[INFO] [stderr]     |
[INFO] [stderr] 382 |         return results;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^ help: remove `return` as shown: `results`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n`
[INFO] [stderr]    --> src/lib.rs:358:13
[INFO] [stderr]     |
[INFO] [stderr] 358 |         for n in 0..num_trees {
[INFO] [stderr]     |             ^ help: consider using `_n` instead
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: you should consider deriving a `Default` implementation for `TreeConfig`
[INFO] [stderr]   --> src/lib.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 | /     pub fn new() -> TreeConfig {
[INFO] [stderr] 20 | |         return TreeConfig {
[INFO] [stderr] 21 | |             decision: "category".to_string(),
[INFO] [stderr] 22 | |             max_depth: 70,
[INFO] [stderr] ...  |
[INFO] [stderr] 25 | |         };
[INFO] [stderr] 26 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::new_without_default_derive)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default_derive
[INFO] [stderr] help: try this
[INFO] [stderr]    |
[INFO] [stderr] 10 | #[derive(Default)]
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:107:33
[INFO] [stderr]     |
[INFO] [stderr] 107 | fn unique_values<'a>(attribute: &String, data: &'a Vec<Item>) -> HashMap<&'a Value, usize> {
[INFO] [stderr]     |                                 ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:107:48
[INFO] [stderr]     |
[INFO] [stderr] 107 | fn unique_values<'a>(attribute: &String, data: &'a Vec<Item>) -> HashMap<&'a Value, usize> {
[INFO] [stderr]     |                                                ^^^^^^^^^^^^^ help: change this to: `&[Item]`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the Vec
[INFO] [stderr]    --> src/lib.rs:109:26
[INFO] [stderr]     |
[INFO] [stderr] 109 |     for mut item in data.into_iter() {
[INFO] [stderr]     |                          ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::into_iter_on_ref)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/lib.rs:111:9
[INFO] [stderr]     |
[INFO] [stderr] 111 | /         match value {
[INFO] [stderr] 112 | |             Some(v) => {
[INFO] [stderr] 113 | |                 let current = counter.entry(v).or_insert(0);
[INFO] [stderr] 114 | |                 *current += 1;
[INFO] [stderr] 115 | |             }
[INFO] [stderr] 116 | |             None => {}
[INFO] [stderr] 117 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::single_match)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 111 |         if let Some(v) = value {
[INFO] [stderr] 112 |     let current = counter.entry(v).or_insert(0);
[INFO] [stderr] 113 |     *current += 1;
[INFO] [stderr] 114 | }
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:123:31
[INFO] [stderr]     |
[INFO] [stderr] 123 | fn value_frequency(attribute: &String, data: &Dataset) -> Option<Value> {
[INFO] [stderr]     |                               ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:123:46
[INFO] [stderr]     |
[INFO] [stderr] 123 | fn value_frequency(attribute: &String, data: &Dataset) -> Option<Value> {
[INFO] [stderr]     |                                              ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:137:31
[INFO] [stderr]     |
[INFO] [stderr] 137 | fn calculate_split(attribute: &String, pivot: &Value, data: &Dataset) -> Split {
[INFO] [stderr]     |                               ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:137:61
[INFO] [stderr]     |
[INFO] [stderr] 137 | fn calculate_split(attribute: &String, pivot: &Value, data: &Dataset) -> Split {
[INFO] [stderr]     |                                                             ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the Vec
[INFO] [stderr]    --> src/lib.rs:141:22
[INFO] [stderr]     |
[INFO] [stderr] 141 |     for item in data.into_iter() {
[INFO] [stderr]     |                      ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/lib.rs:143:9
[INFO] [stderr]     |
[INFO] [stderr] 143 | /         match value {
[INFO] [stderr] 144 | |             Some(v) => {
[INFO] [stderr] 145 | |                 if v == pivot {
[INFO] [stderr] 146 | |                     true_branch.push(item.clone());
[INFO] [stderr] ...   |
[INFO] [stderr] 151 | |             None => {}
[INFO] [stderr] 152 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 143 |         if let Some(v) = value {
[INFO] [stderr] 144 |     if v == pivot {
[INFO] [stderr] 145 |         true_branch.push(item.clone());
[INFO] [stderr] 146 |     } else {
[INFO] [stderr] 147 |         false_branch.push(item.clone());
[INFO] [stderr] 148 |     }
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:166:23
[INFO] [stderr]     |
[INFO] [stderr] 166 | fn entropy(attribute: &String, data: &Dataset) -> f64 {
[INFO] [stderr]     |                       ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:166:38
[INFO] [stderr]     |
[INFO] [stderr] 166 | fn entropy(attribute: &String, data: &Dataset) -> f64 {
[INFO] [stderr]     |                                      ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: called `.get().unwrap()` on a HashMap. Using `[]` is more clear and more concise
[INFO] [stderr]    --> src/lib.rs:242:29
[INFO] [stderr]     |
[INFO] [stderr] 242 |                 let pivot = item.get(attribute).unwrap();
[INFO] [stderr]     |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `&item[attribute]`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::get_unwrap)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#get_unwrap
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:338:25
[INFO] [stderr]     |
[INFO] [stderr] 338 | fn sample_dataset(data: &Dataset, size: usize) -> Dataset {
[INFO] [stderr]     |                         ^^^^^^^^
[INFO] [stderr] 339 |     let mut rng = rand::thread_rng();
[INFO] [stderr] 340 |     let mut shuffled = data.clone();
[INFO] [stderr]     |                        ------------ help: change `data.clone()` to: `data.to_owned()`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:355:63
[INFO] [stderr]     |
[INFO] [stderr] 355 |     pub fn build(attribute: String, config: TreeConfig, data: &Dataset, num_trees: usize, subsample_size: usize) -> RandomForest {
[INFO] [stderr]     |                                                               ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/lib.rs:374:13
[INFO] [stderr]     |
[INFO] [stderr] 374 | /             match value {
[INFO] [stderr] 375 | |                 Some(v) => {
[INFO] [stderr] 376 | |                     let count = results.entry(v).or_insert(0);
[INFO] [stderr] 377 | |                     *count += 1;
[INFO] [stderr] 378 | |                 },
[INFO] [stderr] 379 | |                 None => {}
[INFO] [stderr] 380 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 374 |             if let Some(v) = value {
[INFO] [stderr] 375 |     let count = results.entry(v).or_insert(0);
[INFO] [stderr] 376 |     *count += 1;
[INFO] [stderr] 377 | }
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]   --> src/lib.rs:20:9
[INFO] [stderr]    |
[INFO] [stderr] 20 | /         return TreeConfig {
[INFO] [stderr] 21 | |             decision: "category".to_string(),
[INFO] [stderr] 22 | |             max_depth: 70,
[INFO] [stderr] 23 | |             min_count: 1,
[INFO] [stderr] 24 | |             entropy_threshold: 0.01,
[INFO] [stderr] 25 | |         };
[INFO] [stderr]    | |__________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::needless_return)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]    |
[INFO] [stderr] 20 |         TreeConfig {
[INFO] [stderr] 21 |             decision: "category".to_string(),
[INFO] [stderr] 22 |             max_depth: 70,
[INFO] [stderr] 23 |             min_count: 1,
[INFO] [stderr] 24 |             entropy_threshold: 0.01,
[INFO] [stderr] 25 |         }
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:119:5
[INFO] [stderr]     |
[INFO] [stderr] 119 |     return counter;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^ help: remove `return` as shown: `counter`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:134:5
[INFO] [stderr]     |
[INFO] [stderr] 134 |     return most_frequent_value;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove `return` as shown: `most_frequent_value`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:155:5
[INFO] [stderr]     |
[INFO] [stderr] 155 | /     return Split {
[INFO] [stderr] 156 | |         gain: 0.0,
[INFO] [stderr] 157 | |         true_branch,
[INFO] [stderr] 158 | |         false_branch,
[INFO] [stderr] ...   |
[INFO] [stderr] 162 | |         },
[INFO] [stderr] 163 | |     };
[INFO] [stderr]     | |______^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]     |
[INFO] [stderr] 155 |     Split {
[INFO] [stderr] 156 |         gain: 0.0,
[INFO] [stderr] 157 |         true_branch,
[INFO] [stderr] 158 |         false_branch,
[INFO] [stderr] 159 |         attribute: "category".to_string(),
[INFO] [stderr] 160 |         pivot: Value {
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:174:5
[INFO] [stderr]     |
[INFO] [stderr] 174 |     return entropy;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^ help: remove `return` as shown: `entropy`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:300:13
[INFO] [stderr]     |
[INFO] [stderr] 300 |             return tree;
[INFO] [stderr]     |             ^^^^^^^^^^^^ help: remove `return` as shown: `tree`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:302:13
[INFO] [stderr]     |
[INFO] [stderr] 302 | /             return Some(Box::new(DecisionTree {
[INFO] [stderr] 303 | |                 decision: value_frequency(&config.decision, &data),
[INFO] [stderr] 304 | |                 true_branch: None,
[INFO] [stderr] 305 | |                 false_branch: None,
[INFO] [stderr] 306 | |                 attribute: None,
[INFO] [stderr] 307 | |                 pivot: None,
[INFO] [stderr] 308 | |             }));
[INFO] [stderr]     | |________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]     |
[INFO] [stderr] 302 |             Some(Box::new(DecisionTree {
[INFO] [stderr] 303 |                 decision: value_frequency(&config.decision, &data),
[INFO] [stderr] 304 |                 true_branch: None,
[INFO] [stderr] 305 |                 false_branch: None,
[INFO] [stderr] 306 |                 attribute: None,
[INFO] [stderr] 307 |                 pivot: None,
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:343:5
[INFO] [stderr]     |
[INFO] [stderr] 343 |     return shuffled;
[INFO] [stderr]     |     ^^^^^^^^^^^^^^^^ help: remove `return` as shown: `shuffled`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:364:9
[INFO] [stderr]     |
[INFO] [stderr] 364 | /         return RandomForest {
[INFO] [stderr] 365 | |             trees
[INFO] [stderr] 366 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] help: remove `return` as shown
[INFO] [stderr]     |
[INFO] [stderr] 364 |         RandomForest {
[INFO] [stderr] 365 |             trees
[INFO] [stderr] 366 |         }
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/lib.rs:382:9
[INFO] [stderr]     |
[INFO] [stderr] 382 |         return results;
[INFO] [stderr]     |         ^^^^^^^^^^^^^^^ help: remove `return` as shown: `results`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `n`
[INFO] [stderr]    --> src/lib.rs:358:13
[INFO] [stderr]     |
[INFO] [stderr] 358 |         for n in 0..num_trees {
[INFO] [stderr]     |             ^ help: consider using `_n` instead
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: you should consider deriving a `Default` implementation for `TreeConfig`
[INFO] [stderr]   --> src/lib.rs:19:5
[INFO] [stderr]    |
[INFO] [stderr] 19 | /     pub fn new() -> TreeConfig {
[INFO] [stderr] 20 | |         return TreeConfig {
[INFO] [stderr] 21 | |             decision: "category".to_string(),
[INFO] [stderr] 22 | |             max_depth: 70,
[INFO] [stderr] ...  |
[INFO] [stderr] 25 | |         };
[INFO] [stderr] 26 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::new_without_default_derive)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default_derive
[INFO] [stderr] help: try this
[INFO] [stderr]    |
[INFO] [stderr] 10 | #[derive(Default)]
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:107:33
[INFO] [stderr]     |
[INFO] [stderr] 107 | fn unique_values<'a>(attribute: &String, data: &'a Vec<Item>) -> HashMap<&'a Value, usize> {
[INFO] [stderr]     |                                 ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::ptr_arg)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:107:48
[INFO] [stderr]     |
[INFO] [stderr] 107 | fn unique_values<'a>(attribute: &String, data: &'a Vec<Item>) -> HashMap<&'a Value, usize> {
[INFO] [stderr]     |                                                ^^^^^^^^^^^^^ help: change this to: `&[Item]`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the Vec
[INFO] [stderr]    --> src/lib.rs:109:26
[INFO] [stderr]     |
[INFO] [stderr] 109 |     for mut item in data.into_iter() {
[INFO] [stderr]     |                          ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::into_iter_on_ref)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/lib.rs:111:9
[INFO] [stderr]     |
[INFO] [stderr] 111 | /         match value {
[INFO] [stderr] 112 | |             Some(v) => {
[INFO] [stderr] 113 | |                 let current = counter.entry(v).or_insert(0);
[INFO] [stderr] 114 | |                 *current += 1;
[INFO] [stderr] 115 | |             }
[INFO] [stderr] 116 | |             None => {}
[INFO] [stderr] 117 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::single_match)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 111 |         if let Some(v) = value {
[INFO] [stderr] 112 |     let current = counter.entry(v).or_insert(0);
[INFO] [stderr] 113 |     *current += 1;
[INFO] [stderr] 114 | }
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:123:31
[INFO] [stderr]     |
[INFO] [stderr] 123 | fn value_frequency(attribute: &String, data: &Dataset) -> Option<Value> {
[INFO] [stderr]     |                               ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:123:46
[INFO] [stderr]     |
[INFO] [stderr] 123 | fn value_frequency(attribute: &String, data: &Dataset) -> Option<Value> {
[INFO] [stderr]     |                                              ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:137:31
[INFO] [stderr]     |
[INFO] [stderr] 137 | fn calculate_split(attribute: &String, pivot: &Value, data: &Dataset) -> Split {
[INFO] [stderr]     |                               ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:137:61
[INFO] [stderr]     |
[INFO] [stderr] 137 | fn calculate_split(attribute: &String, pivot: &Value, data: &Dataset) -> Split {
[INFO] [stderr]     |                                                             ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: this .into_iter() call is equivalent to .iter() and will not move the Vec
[INFO] [stderr]    --> src/lib.rs:141:22
[INFO] [stderr]     |
[INFO] [stderr] 141 |     for item in data.into_iter() {
[INFO] [stderr]     |                      ^^^^^^^^^ help: call directly: `iter`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#into_iter_on_ref
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/lib.rs:143:9
[INFO] [stderr]     |
[INFO] [stderr] 143 | /         match value {
[INFO] [stderr] 144 | |             Some(v) => {
[INFO] [stderr] 145 | |                 if v == pivot {
[INFO] [stderr] 146 | |                     true_branch.push(item.clone());
[INFO] [stderr] ...   |
[INFO] [stderr] 151 | |             None => {}
[INFO] [stderr] 152 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 143 |         if let Some(v) = value {
[INFO] [stderr] 144 |     if v == pivot {
[INFO] [stderr] 145 |         true_branch.push(item.clone());
[INFO] [stderr] 146 |     } else {
[INFO] [stderr] 147 |         false_branch.push(item.clone());
[INFO] [stderr] 148 |     }
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&String` instead of `&str` involves a new object where a slice will do.
[INFO] [stderr]    --> src/lib.rs:166:23
[INFO] [stderr]     |
[INFO] [stderr] 166 | fn entropy(attribute: &String, data: &Dataset) -> f64 {
[INFO] [stderr]     |                       ^^^^^^^ help: change this to: `&str`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:166:38
[INFO] [stderr]     |
[INFO] [stderr] 166 | fn entropy(attribute: &String, data: &Dataset) -> f64 {
[INFO] [stderr]     |                                      ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: called `.get().unwrap()` on a HashMap. Using `[]` is more clear and more concise
[INFO] [stderr]    --> src/lib.rs:242:29
[INFO] [stderr]     |
[INFO] [stderr] 242 |                 let pivot = item.get(attribute).unwrap();
[INFO] [stderr]     |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `&item[attribute]`
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::get_unwrap)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#get_unwrap
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:338:25
[INFO] [stderr]     |
[INFO] [stderr] 338 | fn sample_dataset(data: &Dataset, size: usize) -> Dataset {
[INFO] [stderr]     |                         ^^^^^^^^
[INFO] [stderr] 339 |     let mut rng = rand::thread_rng();
[INFO] [stderr] 340 |     let mut shuffled = data.clone();
[INFO] [stderr]     |                        ------------ help: change `data.clone()` to: `data.to_owned()`
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: writing `&Vec<_>` instead of `&[_]` involves one more reference and cannot be used with non-Vec-based slices.
[INFO] [stderr]    --> src/lib.rs:355:63
[INFO] [stderr]     |
[INFO] [stderr] 355 |     pub fn build(attribute: String, config: TreeConfig, data: &Dataset, num_trees: usize, subsample_size: usize) -> RandomForest {
[INFO] [stderr]     |                                                               ^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_arg
[INFO] [stderr] 
[INFO] [stderr] warning: you seem to be trying to use match for destructuring a single pattern. Consider using `if let`
[INFO] [stderr]    --> src/lib.rs:374:13
[INFO] [stderr]     |
[INFO] [stderr] 374 | /             match value {
[INFO] [stderr] 375 | |                 Some(v) => {
[INFO] [stderr] 376 | |                     let count = results.entry(v).or_insert(0);
[INFO] [stderr] 377 | |                     *count += 1;
[INFO] [stderr] 378 | |                 },
[INFO] [stderr] 379 | |                 None => {}
[INFO] [stderr] 380 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 374 |             if let Some(v) = value {
[INFO] [stderr] 375 |     let count = results.entry(v).or_insert(0);
[INFO] [stderr] 376 |     *count += 1;
[INFO] [stderr] 377 | }
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: called `.get().unwrap()` on a HashMap. Using `[]` is more clear and more concise
[INFO] [stderr]    --> src/lib.rs:453:14
[INFO] [stderr]     |
[INFO] [stderr] 453 |               *unique
[INFO] [stderr]     |  ______________^
[INFO] [stderr] 454 | |                 .get(&Value {
[INFO] [stderr] 455 | |                     data: "rust".to_string()
[INFO] [stderr] 456 | |                 })
[INFO] [stderr] 457 | |                 .unwrap(),
[INFO] [stderr]     | |_________________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#get_unwrap
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 453 |             *&unique[&Value {
[INFO] [stderr] 454 |                     data: "rust".to_string()
[INFO] [stderr] 455 |                 }],
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr] warning: called `.get().unwrap()` on a HashMap. Using `[]` is more clear and more concise
[INFO] [stderr]    --> src/lib.rs:461:14
[INFO] [stderr]     |
[INFO] [stderr] 461 |               *unique
[INFO] [stderr]     |  ______________^
[INFO] [stderr] 462 | |                 .get(&Value {
[INFO] [stderr] 463 | |                     data: "python".to_string()
[INFO] [stderr] 464 | |                 })
[INFO] [stderr] 465 | |                 .unwrap(),
[INFO] [stderr]     | |_________________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#get_unwrap
[INFO] [stderr] help: try this
[INFO] [stderr]     |
[INFO] [stderr] 461 |             *&unique[&Value {
[INFO] [stderr] 462 |                     data: "python".to_string()
[INFO] [stderr] 463 |                 }],
[INFO] [stderr]     |
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.25s
[INFO] running `"docker" "inspect" "74143087a5e324c2369a13745004e9afd7da18f429ce4fc800424d5969e70d93"`
[INFO] running `"docker" "rm" "-f" "74143087a5e324c2369a13745004e9afd7da18f429ce4fc800424d5969e70d93"`
[INFO] [stdout] 74143087a5e324c2369a13745004e9afd7da18f429ce4fc800424d5969e70d93