[INFO] crate coll 0.1.3 is already in cache
[INFO] extracting crate coll 0.1.3 into work/ex/clippy-test-run/sources/stable/reg/coll/0.1.3
[INFO] extracting crate coll 0.1.3 into work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/coll/0.1.3
[INFO] validating manifest of coll-0.1.3 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 coll-0.1.3 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 coll-0.1.3
[INFO] finished frobbing coll-0.1.3
[INFO] frobbed toml for coll-0.1.3 written to work/ex/clippy-test-run/sources/stable/reg/coll/0.1.3/Cargo.toml
[INFO] started frobbing coll-0.1.3
[INFO] finished frobbing coll-0.1.3
[INFO] frobbed toml for coll-0.1.3 written to work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/coll/0.1.3/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 coll-0.1.3 against stable+rustflags=-Dclippy::into_iter_on_array for clippy-test-run
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/clippy-test-run/worker-0/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/clippy-test-run/sources/stable+rustflags=-Dclippy%3A%3Ainto_iter_on_array/reg/coll/0.1.3:/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 -Dclippy::into_iter_on_array" "-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] a6e56a25f81b40c87fd3319f5f9aaea075e27acbc6c238b2cd769a311e0c9306
[INFO] running `"docker" "start" "-a" "a6e56a25f81b40c87fd3319f5f9aaea075e27acbc6c238b2cd769a311e0c9306"`
[INFO] [stderr]     Checking coll v0.1.3 (/opt/crater/workdir)
[INFO] [stderr] warning: redundant field names in struct initialization
[INFO] [stderr]   --> src/persistent/rbtree.rs:56:16
[INFO] [stderr]    |
[INFO] [stderr] 56 |         Iter { lefts: lefts, len: wrapper.len }
[INFO] [stderr]    |                ^^^^^^^^^^^^ help: replace it with: `lefts`
[INFO] [stderr]    |
[INFO] [stderr] warning: redundant field names in struct initialization
[INFO] [stderr]   --> src/persistent/rbtree.rs:56:16
[INFO] [stderr]    |
[INFO] [stderr] 56 |         Iter { lefts: lefts, len: wrapper.len }
[INFO] [stderr]    |                ^^^^^^^^^^^^ help: replace it with: `lefts`
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::redundant_field_names)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_field_names
[INFO] [stderr] 
[INFO] [stderr] warning: 5th binding whose name is just one char
[INFO] [stderr]    --> src/persistent/rbtree.rs:251:55
[INFO] [stderr]     |
[INFO] [stderr] 251 |                 &Tree::T(ref color, ref l, ref y, ref r) if x < **y => {
[INFO] [stderr]     |                                                       ^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::many_single_char_names)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 5th binding whose name is just one char
[INFO] [stderr]    --> src/persistent/rbtree.rs:257:55
[INFO] [stderr]     |
[INFO] [stderr] 257 |                 &Tree::T(ref color, ref l, ref y, ref r) if x > **y => {
[INFO] [stderr]     |                                                       ^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr]    = note: #[warn(clippy::redundant_field_names)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_field_names
[INFO] [stderr] 
[INFO] [stderr] warning: 5th binding whose name is just one char
[INFO] [stderr]    --> src/persistent/rbtree.rs:251:55
[INFO] [stderr]     |
[INFO] [stderr] 251 |                 &Tree::T(ref color, ref l, ref y, ref r) if x < **y => {
[INFO] [stderr]     |                                                       ^
[INFO] [stderr]     |
[INFO] [stderr]     = note: #[warn(clippy::many_single_char_names)] on by default
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: 5th binding whose name is just one char
[INFO] [stderr]    --> src/persistent/rbtree.rs:257:55
[INFO] [stderr]     |
[INFO] [stderr] 257 |                 &Tree::T(ref color, ref l, ref y, ref r) if x > **y => {
[INFO] [stderr]     |                                                       ^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#many_single_char_names
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/persistent/rbtree.rs:226:9
[INFO] [stderr]     |
[INFO] [stderr] 226 |         return self;
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: remove `return` as shown: `self`
[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] 
[INFO] [stderr] warning: you seem to be trying to use `Box<Vec<T>>`. Consider using just `Vec<T>`
[INFO] [stderr]   --> src/persistent/rbtree.rs:36:12
[INFO] [stderr]    |
[INFO] [stderr] 36 |     lefts: Box<Vec<&'a Tree<T>>>,
[INFO] [stderr]    |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::box_vec)] on by default
[INFO] [stderr]    = help: `Vec<T>` is already on the heap, `Box<Vec<T>>` makes an extra allocation.
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#box_vec
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/persistent/rbtree.rs:45:9
[INFO] [stderr]    |
[INFO] [stderr] 45 | /         if let &Tree::T(_, ref l, _, _) = curr {
[INFO] [stderr] 46 | |             curr = l.as_ref();
[INFO] [stderr] 47 | |         }
[INFO] [stderr]    | |_________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::match_ref_pats)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 45 |         if let Tree::T(_, ref l, _, _) = *curr {
[INFO] [stderr]    |                ^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you should consider adding a `Default` implementation for `persistent::rbtree::RbTree<T>`
[INFO] [stderr]   --> src/persistent/rbtree.rs:81:5
[INFO] [stderr]    |
[INFO] [stderr] 81 | /     pub fn new() -> RbTree<T> {
[INFO] [stderr] 82 | |         RbTree {
[INFO] [stderr] 83 | |             tree: Rc::new(Tree::E),
[INFO] [stderr] 84 | |             len: 0
[INFO] [stderr] 85 | |         }
[INFO] [stderr] 86 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::new_without_default)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default
[INFO] [stderr] help: try this
[INFO] [stderr]    |
[INFO] [stderr] 79 | impl Default for persistent::rbtree::RbTree<T> {
[INFO] [stderr] 80 |     fn default() -> Self {
[INFO] [stderr] 81 |         Self::new()
[INFO] [stderr] 82 |     }
[INFO] [stderr] 83 | }
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:190:13
[INFO] [stderr]     |
[INFO] [stderr] 190 | /             if let &Tree::T(Color::Red, ref l2, ref x2, ref r2) = l.as_ref() {
[INFO] [stderr] 191 | | 
[INFO] [stderr] 192 | |                 // Black (Red (Red (l3, x3, r3), x2, r2), x, r)
[INFO] [stderr] 193 | |                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] ...   |
[INFO] [stderr] 205 | | 
[INFO] [stderr] 206 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 190 |             if let Tree::T(Color::Red, ref l2, ref x2, ref r2) = *l.as_ref() {
[INFO] [stderr]     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:193:17
[INFO] [stderr]     |
[INFO] [stderr] 193 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] 194 | |                     let left = Rc::new(Tree::T(Color::Black, l3.clone(), x3.clone(), r3.clone()));
[INFO] [stderr] 195 | |                     let right = Rc::new(Tree::T(Color::Black, r2.clone(), x.clone(), r.clone()));
[INFO] [stderr] 196 | |                     return Tree::T(Color::Red, left, x2.clone(), right);
[INFO] [stderr] 197 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 193 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *l2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:200:17
[INFO] [stderr]     |
[INFO] [stderr] 200 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = r2.as_ref() {
[INFO] [stderr] 201 | |                     let left = Rc::new(Tree::T(Color::Black, l2.clone(), x2.clone(), l3.clone()));
[INFO] [stderr] 202 | |                     let right = Rc::new(Tree::T(Color::Black, r3.clone(), x.clone(), r.clone()));
[INFO] [stderr] 203 | |                     return Tree::T(Color::Red, left, x3.clone(), right);
[INFO] [stderr] 204 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 200 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *r2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:208:13
[INFO] [stderr]     |
[INFO] [stderr] 208 | /             if let &Tree::T(Color::Red, ref l2, ref x2, ref r2) = r.as_ref() {
[INFO] [stderr] 209 | | 
[INFO] [stderr] 210 | |                 // Black (l, x, (Red (Red (l3, x3, r3), x2, r2)))
[INFO] [stderr] 211 | |                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] ...   |
[INFO] [stderr] 222 | |                 }
[INFO] [stderr] 223 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 208 |             if let Tree::T(Color::Red, ref l2, ref x2, ref r2) = *r.as_ref() {
[INFO] [stderr]     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:211:17
[INFO] [stderr]     |
[INFO] [stderr] 211 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] 212 | |                     let left = Rc::new(Tree::T(Color::Black, l.clone(), x.clone(), l3.clone()));
[INFO] [stderr] 213 | |                     let right = Rc::new(Tree::T(Color::Black, r3.clone(), x2.clone(), r2.clone()));
[INFO] [stderr] 214 | |                     return Tree::T(Color::Red, left, x3.clone(), right);
[INFO] [stderr] 215 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 211 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *l2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:218:17
[INFO] [stderr]     |
[INFO] [stderr] 218 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = r2.as_ref() {
[INFO] [stderr] 219 | |                     let left = Rc::new(Tree::T(Color::Black, l.clone(), x.clone(), l2.clone()));
[INFO] [stderr] 220 | |                     let right = Rc::new(Tree::T(Color::Black, l3.clone(), x3.clone(), r3.clone()));
[INFO] [stderr] 221 | |                     return Tree::T(Color::Red, left, x2.clone(), right);
[INFO] [stderr] 222 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 218 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *r2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:230:9
[INFO] [stderr]     |
[INFO] [stderr] 230 | /         match self {
[INFO] [stderr] 231 | |             &Tree::T(_, ref left, ref y, ref right) => {
[INFO] [stderr] 232 | |                 if x < **y {
[INFO] [stderr] 233 | |                     left.contains(x)
[INFO] [stderr] ...   |
[INFO] [stderr] 240 | |             &Tree::E => false,
[INFO] [stderr] 241 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 230 |         match *self {
[INFO] [stderr] 231 |             Tree::T(_, ref left, ref y, ref right) => {
[INFO] [stderr] 232 |                 if x < **y {
[INFO] [stderr] 233 |                     left.contains(x)
[INFO] [stderr] 234 |                 } else if x > **y {
[INFO] [stderr] 235 |                     right.contains(x)
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:248:13
[INFO] [stderr]     |
[INFO] [stderr] 248 | /             match t {
[INFO] [stderr] 249 | |                 &Tree::E => Tree::T(Color::Red, empty.clone(), Rc::new(x), empty.clone()),
[INFO] [stderr] 250 | | 
[INFO] [stderr] 251 | |                 &Tree::T(ref color, ref l, ref y, ref r) if x < **y => {
[INFO] [stderr] ...   |
[INFO] [stderr] 265 | |                 }
[INFO] [stderr] 266 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 248 |             match *t {
[INFO] [stderr] 249 |                 Tree::E => Tree::T(Color::Red, empty.clone(), Rc::new(x), empty.clone()),
[INFO] [stderr] 250 | 
[INFO] [stderr] 251 |                 Tree::T(ref color, ref l, ref y, ref r) if x < **y => {
[INFO] [stderr] 252 |                     let left = Rc::new(ins(l, x));
[INFO] [stderr] 253 |                     let result = Tree::T(color.clone(), left, y.clone(), r.clone());
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: unneeded return statement
[INFO] [stderr]    --> src/persistent/rbtree.rs:226:9
[INFO] [stderr]     |
[INFO] [stderr] 226 |         return self;
[INFO] [stderr]     |         ^^^^^^^^^^^^ help: remove `return` as shown: `self`
[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] 
[INFO] [stderr] warning: you seem to be trying to use `Box<Vec<T>>`. Consider using just `Vec<T>`
[INFO] [stderr]   --> src/persistent/rbtree.rs:36:12
[INFO] [stderr]    |
[INFO] [stderr] 36 |     lefts: Box<Vec<&'a Tree<T>>>,
[INFO] [stderr]    |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::box_vec)] on by default
[INFO] [stderr]    = help: `Vec<T>` is already on the heap, `Box<Vec<T>>` makes an extra allocation.
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#box_vec
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]   --> src/persistent/rbtree.rs:45:9
[INFO] [stderr]    |
[INFO] [stderr] 45 | /         if let &Tree::T(_, ref l, _, _) = curr {
[INFO] [stderr] 46 | |             curr = l.as_ref();
[INFO] [stderr] 47 | |         }
[INFO] [stderr]    | |_________^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::match_ref_pats)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]    |
[INFO] [stderr] 45 |         if let Tree::T(_, ref l, _, _) = *curr {
[INFO] [stderr]    |                ^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you should consider adding a `Default` implementation for `persistent::rbtree::RbTree<T>`
[INFO] [stderr]   --> src/persistent/rbtree.rs:81:5
[INFO] [stderr]    |
[INFO] [stderr] 81 | /     pub fn new() -> RbTree<T> {
[INFO] [stderr] 82 | |         RbTree {
[INFO] [stderr] 83 | |             tree: Rc::new(Tree::E),
[INFO] [stderr] 84 | |             len: 0
[INFO] [stderr] 85 | |         }
[INFO] [stderr] 86 | |     }
[INFO] [stderr]    | |_____^
[INFO] [stderr]    |
[INFO] [stderr]    = note: #[warn(clippy::new_without_default)] on by default
[INFO] [stderr]    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default
[INFO] [stderr] help: try this
[INFO] [stderr]    |
[INFO] [stderr] 79 | impl Default for persistent::rbtree::RbTree<T> {
[INFO] [stderr] 80 |     fn default() -> Self {
[INFO] [stderr] 81 |         Self::new()
[INFO] [stderr] 82 |     }
[INFO] [stderr] 83 | }
[INFO] [stderr]    |
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:190:13
[INFO] [stderr]     |
[INFO] [stderr] 190 | /             if let &Tree::T(Color::Red, ref l2, ref x2, ref r2) = l.as_ref() {
[INFO] [stderr] 191 | | 
[INFO] [stderr] 192 | |                 // Black (Red (Red (l3, x3, r3), x2, r2), x, r)
[INFO] [stderr] 193 | |                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] ...   |
[INFO] [stderr] 205 | | 
[INFO] [stderr] 206 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 190 |             if let Tree::T(Color::Red, ref l2, ref x2, ref r2) = *l.as_ref() {
[INFO] [stderr]     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:193:17
[INFO] [stderr]     |
[INFO] [stderr] 193 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] 194 | |                     let left = Rc::new(Tree::T(Color::Black, l3.clone(), x3.clone(), r3.clone()));
[INFO] [stderr] 195 | |                     let right = Rc::new(Tree::T(Color::Black, r2.clone(), x.clone(), r.clone()));
[INFO] [stderr] 196 | |                     return Tree::T(Color::Red, left, x2.clone(), right);
[INFO] [stderr] 197 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 193 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *l2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:200:17
[INFO] [stderr]     |
[INFO] [stderr] 200 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = r2.as_ref() {
[INFO] [stderr] 201 | |                     let left = Rc::new(Tree::T(Color::Black, l2.clone(), x2.clone(), l3.clone()));
[INFO] [stderr] 202 | |                     let right = Rc::new(Tree::T(Color::Black, r3.clone(), x.clone(), r.clone()));
[INFO] [stderr] 203 | |                     return Tree::T(Color::Red, left, x3.clone(), right);
[INFO] [stderr] 204 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 200 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *r2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:208:13
[INFO] [stderr]     |
[INFO] [stderr] 208 | /             if let &Tree::T(Color::Red, ref l2, ref x2, ref r2) = r.as_ref() {
[INFO] [stderr] 209 | | 
[INFO] [stderr] 210 | |                 // Black (l, x, (Red (Red (l3, x3, r3), x2, r2)))
[INFO] [stderr] 211 | |                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] ...   |
[INFO] [stderr] 222 | |                 }
[INFO] [stderr] 223 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 208 |             if let Tree::T(Color::Red, ref l2, ref x2, ref r2) = *r.as_ref() {
[INFO] [stderr]     |                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:211:17
[INFO] [stderr]     |
[INFO] [stderr] 211 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = l2.as_ref() {
[INFO] [stderr] 212 | |                     let left = Rc::new(Tree::T(Color::Black, l.clone(), x.clone(), l3.clone()));
[INFO] [stderr] 213 | |                     let right = Rc::new(Tree::T(Color::Black, r3.clone(), x2.clone(), r2.clone()));
[INFO] [stderr] 214 | |                     return Tree::T(Color::Red, left, x3.clone(), right);
[INFO] [stderr] 215 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 211 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *l2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:218:17
[INFO] [stderr]     |
[INFO] [stderr] 218 | /                 if let &Tree::T(Color::Red, ref l3, ref x3, ref r3) = r2.as_ref() {
[INFO] [stderr] 219 | |                     let left = Rc::new(Tree::T(Color::Black, l.clone(), x.clone(), l2.clone()));
[INFO] [stderr] 220 | |                     let right = Rc::new(Tree::T(Color::Black, l3.clone(), x3.clone(), r3.clone()));
[INFO] [stderr] 221 | |                     return Tree::T(Color::Red, left, x2.clone(), right);
[INFO] [stderr] 222 | |                 }
[INFO] [stderr]     | |_________________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 218 |                 if let Tree::T(Color::Red, ref l3, ref x3, ref r3) = *r2.as_ref() {
[INFO] [stderr]     |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^   ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:230:9
[INFO] [stderr]     |
[INFO] [stderr] 230 | /         match self {
[INFO] [stderr] 231 | |             &Tree::T(_, ref left, ref y, ref right) => {
[INFO] [stderr] 232 | |                 if x < **y {
[INFO] [stderr] 233 | |                     left.contains(x)
[INFO] [stderr] ...   |
[INFO] [stderr] 240 | |             &Tree::E => false,
[INFO] [stderr] 241 | |         }
[INFO] [stderr]     | |_________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 230 |         match *self {
[INFO] [stderr] 231 |             Tree::T(_, ref left, ref y, ref right) => {
[INFO] [stderr] 232 |                 if x < **y {
[INFO] [stderr] 233 |                     left.contains(x)
[INFO] [stderr] 234 |                 } else if x > **y {
[INFO] [stderr] 235 |                     right.contains(x)
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr] warning: you don't need to add `&` to all patterns
[INFO] [stderr]    --> src/persistent/rbtree.rs:248:13
[INFO] [stderr]     |
[INFO] [stderr] 248 | /             match t {
[INFO] [stderr] 249 | |                 &Tree::E => Tree::T(Color::Red, empty.clone(), Rc::new(x), empty.clone()),
[INFO] [stderr] 250 | | 
[INFO] [stderr] 251 | |                 &Tree::T(ref color, ref l, ref y, ref r) if x < **y => {
[INFO] [stderr] ...   |
[INFO] [stderr] 265 | |                 }
[INFO] [stderr] 266 | |             }
[INFO] [stderr]     | |_____________^
[INFO] [stderr]     |
[INFO] [stderr]     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#match_ref_pats
[INFO] [stderr] help: instead of prefixing all patterns with `&`, you can dereference the expression
[INFO] [stderr]     |
[INFO] [stderr] 248 |             match *t {
[INFO] [stderr] 249 |                 Tree::E => Tree::T(Color::Red, empty.clone(), Rc::new(x), empty.clone()),
[INFO] [stderr] 250 | 
[INFO] [stderr] 251 |                 Tree::T(ref color, ref l, ref y, ref r) if x < **y => {
[INFO] [stderr] 252 |                     let left = Rc::new(ins(l, x));
[INFO] [stderr] 253 |                     let result = Tree::T(color.clone(), left, y.clone(), r.clone());
[INFO] [stderr]   ...
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.78s
[INFO] running `"docker" "inspect" "a6e56a25f81b40c87fd3319f5f9aaea075e27acbc6c238b2cd769a311e0c9306"`
[INFO] running `"docker" "rm" "-f" "a6e56a25f81b40c87fd3319f5f9aaea075e27acbc6c238b2cd769a311e0c9306"`
[INFO] [stdout] a6e56a25f81b40c87fd3319f5f9aaea075e27acbc6c238b2cd769a311e0c9306