error: struct `PubOne` has a public `len` method, but no `is_empty` method
  --> tests/ui/len_without_is_empty.rs:7:5
   |
LL |     pub fn len(&self) -> isize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `-D clippy::len-without-is-empty` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::len_without_is_empty)]`

error: trait `PubTraitsToo` has a `len` method but no (possibly inherited) `is_empty` method
  --> tests/ui/len_without_is_empty.rs:57:1
   |
LL | / pub trait PubTraitsToo {
LL | |
LL | |     fn len(&self) -> isize;
LL | | }
   | |_^

error: struct `HasIsEmpty` has a public `len` method, but a private `is_empty` method
  --> tests/ui/len_without_is_empty.rs:71:5
   |
LL |     pub fn len(&self) -> isize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: `is_empty` defined here
  --> tests/ui/len_without_is_empty.rs:76:5
   |
LL |     fn is_empty(&self) -> bool {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^

error: struct `HasWrongIsEmpty` has a public `len` method, but the `is_empty` method has an unexpected signature
  --> tests/ui/len_without_is_empty.rs:84:5
   |
LL |     pub fn len(&self) -> isize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: `is_empty` defined here
  --> tests/ui/len_without_is_empty.rs:89:5
   |
LL |     pub fn is_empty(&self, x: u32) -> bool {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: expected signature: `(&self) -> bool`

error: struct `MismatchedSelf` has a public `len` method, but the `is_empty` method has an unexpected signature
  --> tests/ui/len_without_is_empty.rs:97:5
   |
LL |     pub fn len(self) -> isize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: `is_empty` defined here
  --> tests/ui/len_without_is_empty.rs:102:5
   |
LL |     pub fn is_empty(&self) -> bool {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: expected signature: `(self) -> bool`

error: trait `DependsOnFoo` has a `len` method but no (possibly inherited) `is_empty` method
  --> tests/ui/len_without_is_empty.rs:177:1
   |
LL | / pub trait DependsOnFoo: Foo {
LL | |
LL | |     fn len(&mut self) -> usize;
LL | | }
   | |_^

error: struct `OptionalLen3` has a public `len` method, but the `is_empty` method has an unexpected signature
  --> tests/ui/len_without_is_empty.rs:223:5
   |
LL |     pub fn len(&self) -> usize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: `is_empty` defined here
  --> tests/ui/len_without_is_empty.rs:229:5
   |
LL |     pub fn is_empty(&self) -> Option<bool> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: expected signature: `(&self) -> bool`

error: struct `ResultLen` has a public `len` method, but the `is_empty` method has an unexpected signature
  --> tests/ui/len_without_is_empty.rs:236:5
   |
LL |     pub fn len(&self) -> Result<usize, ()> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: `is_empty` defined here
  --> tests/ui/len_without_is_empty.rs:243:5
   |
LL |     pub fn is_empty(&self) -> Option<bool> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   = note: expected signature: `(&self) -> bool` or `(&self) -> Result<bool>

error: this returns a `Result<_, ()>`
  --> tests/ui/len_without_is_empty.rs:236:5
   |
LL |     pub fn len(&self) -> Result<usize, ()> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: use a custom `Error` type instead
   = note: `-D clippy::result-unit-err` implied by `-D warnings`
   = help: to override `-D warnings` add `#[allow(clippy::result_unit_err)]`

error: this returns a `Result<_, ()>`
  --> tests/ui/len_without_is_empty.rs:250:5
   |
LL |     pub fn len(&self) -> Result<usize, ()> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: use a custom `Error` type instead

error: this returns a `Result<_, ()>`
  --> tests/ui/len_without_is_empty.rs:255:5
   |
LL |     pub fn is_empty(&self) -> Result<bool, ()> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: use a custom `Error` type instead

error: this returns a `Result<_, ()>`
  --> tests/ui/len_without_is_empty.rs:263:5
   |
LL |     pub fn len(&self) -> Result<usize, ()> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = help: use a custom `Error` type instead

error: struct `AsyncLenWithoutIsEmpty` has a public `len` method, but no `is_empty` method
  --> tests/ui/len_without_is_empty.rs:305:5
   |
LL |     pub async fn len(&self) -> usize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: struct `AsyncOptionLenWithoutIsEmpty` has a public `len` method, but no `is_empty` method
  --> tests/ui/len_without_is_empty.rs:318:5
   |
LL |     pub async fn len(&self) -> Option<usize> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: struct `AsyncResultLenWithoutIsEmpty` has a public `len` method, but no `is_empty` method
  --> tests/ui/len_without_is_empty.rs:340:5
   |
LL |     pub async fn len(&self) -> Result<usize, ()> {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: type `Alias2` has a public `len` method, but no `is_empty` method
  --> tests/ui/len_without_is_empty.rs:456:5
   |
LL |     pub fn len(&self) -> usize {
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^

error: aborting due to 16 previous errors