Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add run-rustfix for len_zero lint #3978

Merged
merged 1 commit into from Apr 18, 2019
Merged
Changes from all commits
Commits
File filter...
Filter file types
Jump to…
Jump to file or symbol
Failed to load files and symbols.
+367 −163
Diff settings

Always

Just for now

@@ -0,0 +1,145 @@
#![warn(clippy::len_without_is_empty)]
#![allow(dead_code, unused)]

pub struct PubOne;

impl PubOne {
pub fn len(self: &Self) -> isize {
1
}
}

impl PubOne {
// A second impl for this struct -- the error span shouldn't mention this.
pub fn irrelevant(self: &Self) -> bool {
false
}
}

// Identical to `PubOne`, but with an `allow` attribute on the impl complaining `len`.
pub struct PubAllowed;

#[allow(clippy::len_without_is_empty)]
impl PubAllowed {
pub fn len(self: &Self) -> isize {
1
}
}

// No `allow` attribute on this impl block, but that doesn't matter -- we only require one on the
// impl containing `len`.
impl PubAllowed {
pub fn irrelevant(self: &Self) -> bool {
false
}
}

pub trait PubTraitsToo {
fn len(self: &Self) -> isize;
}

impl PubTraitsToo for One {
fn len(self: &Self) -> isize {
0
}
}

pub struct HasIsEmpty;

impl HasIsEmpty {
pub fn len(self: &Self) -> isize {
1
}

fn is_empty(self: &Self) -> bool {
false
}
}

pub struct HasWrongIsEmpty;

impl HasWrongIsEmpty {
pub fn len(self: &Self) -> isize {
1
}

pub fn is_empty(self: &Self, x: u32) -> bool {
false
}
}

struct NotPubOne;

impl NotPubOne {
pub fn len(self: &Self) -> isize {
// No error; `len` is pub but `NotPubOne` is not exported anyway.
1
}
}

struct One;

impl One {
fn len(self: &Self) -> isize {
// No error; `len` is private; see issue #1085.
1
}
}

trait TraitsToo {
fn len(self: &Self) -> isize;
// No error; `len` is private; see issue #1085.
}

impl TraitsToo for One {
fn len(self: &Self) -> isize {
0
}
}

struct HasPrivateIsEmpty;

impl HasPrivateIsEmpty {
pub fn len(self: &Self) -> isize {
1
}

fn is_empty(self: &Self) -> bool {
false
}
}

struct Wither;

pub trait WithIsEmpty {
fn len(self: &Self) -> isize;
fn is_empty(self: &Self) -> bool;
}

impl WithIsEmpty for Wither {
fn len(self: &Self) -> isize {
1
}

fn is_empty(self: &Self) -> bool {
false
}
}

pub trait Empty {
fn is_empty(&self) -> bool;
}

pub trait InheritingEmpty: Empty {
// Must not trigger `LEN_WITHOUT_IS_EMPTY`.
fn len(&self) -> isize;
}

// This used to ICE.
pub trait Foo: Sized {}

pub trait DependsOnFoo: Foo {
fn len(&mut self) -> usize;
}

fn main() {}
@@ -0,0 +1,54 @@
error: item `PubOne` has a public `len` method but no corresponding `is_empty` method
--> $DIR/len_without_is_empty.rs:6:1
|
LL | / impl PubOne {
LL | | pub fn len(self: &Self) -> isize {
LL | | 1
LL | | }
LL | | }
| |_^
|
= note: `-D clippy::len-without-is-empty` implied by `-D warnings`

error: trait `PubTraitsToo` has a `len` method but no (possibly inherited) `is_empty` method
--> $DIR/len_without_is_empty.rs:37:1
|
LL | / pub trait PubTraitsToo {
LL | | fn len(self: &Self) -> isize;
LL | | }
| |_^

error: item `HasIsEmpty` has a public `len` method but a private `is_empty` method
--> $DIR/len_without_is_empty.rs:49:1
|
LL | / impl HasIsEmpty {
LL | | pub fn len(self: &Self) -> isize {
LL | | 1
LL | | }
... |
LL | | }
LL | | }
| |_^

error: item `HasWrongIsEmpty` has a public `len` method but no corresponding `is_empty` method
--> $DIR/len_without_is_empty.rs:61:1
|
LL | / impl HasWrongIsEmpty {
LL | | pub fn len(self: &Self) -> isize {
LL | | 1
LL | | }
... |
LL | | }
LL | | }
| |_^

error: trait `DependsOnFoo` has a `len` method but no (possibly inherited) `is_empty` method
--> $DIR/len_without_is_empty.rs:141:1
|
LL | / pub trait DependsOnFoo: Foo {
LL | | fn len(&mut self) -> usize;
LL | | }
| |_^

error: aborting due to 5 previous errors

@@ -0,0 +1,143 @@
// run-rustfix

#![warn(clippy::len_zero)]
#![allow(dead_code, unused, clippy::len_without_is_empty)]

pub struct One;
struct Wither;

trait TraitsToo {
fn len(self: &Self) -> isize;
// No error; `len` is private; see issue #1085.
}

impl TraitsToo for One {
fn len(self: &Self) -> isize {
0
}
}

pub struct HasIsEmpty;

impl HasIsEmpty {
pub fn len(self: &Self) -> isize {
1
}

fn is_empty(self: &Self) -> bool {
false
}
}

pub struct HasWrongIsEmpty;

impl HasWrongIsEmpty {
pub fn len(self: &Self) -> isize {
1
}

pub fn is_empty(self: &Self, x: u32) -> bool {
false
}
}

pub trait WithIsEmpty {
fn len(self: &Self) -> isize;
fn is_empty(self: &Self) -> bool;
}

impl WithIsEmpty for Wither {
fn len(self: &Self) -> isize {
1
}

fn is_empty(self: &Self) -> bool {
false
}
}

fn main() {
let x = [1, 2];
if x.is_empty() {
println!("This should not happen!");
}

if "".is_empty() {}

let y = One;
if y.len() == 0 {
// No error; `One` does not have `.is_empty()`.
println!("This should not happen either!");
}

let z: &TraitsToo = &y;
if z.len() > 0 {
// No error; `TraitsToo` has no `.is_empty()` method.
println!("Nor should this!");
}

let has_is_empty = HasIsEmpty;
if has_is_empty.is_empty() {
println!("Or this!");
}
if !has_is_empty.is_empty() {
println!("Or this!");
}
if !has_is_empty.is_empty() {
println!("Or this!");
}
if has_is_empty.is_empty() {
println!("Or this!");
}
if !has_is_empty.is_empty() {
println!("Or this!");
}
if has_is_empty.len() > 1 {
// No error.
println!("This can happen.");
}
if has_is_empty.len() <= 1 {
// No error.
println!("This can happen.");
}
if has_is_empty.is_empty() {
println!("Or this!");
}
if !has_is_empty.is_empty() {
println!("Or this!");
}
if !has_is_empty.is_empty() {
println!("Or this!");
}
if !has_is_empty.is_empty() {
println!("Or this!");
}
if has_is_empty.is_empty() {
println!("Or this!");
}
if 1 < has_is_empty.len() {
// No error.
println!("This can happen.");
}
if 1 >= has_is_empty.len() {
// No error.
println!("This can happen.");
}
assert!(!has_is_empty.is_empty());

let with_is_empty: &WithIsEmpty = &Wither;
if with_is_empty.is_empty() {
println!("Or this!");
}
assert!(!with_is_empty.is_empty());

let has_wrong_is_empty = HasWrongIsEmpty;
if has_wrong_is_empty.len() == 0 {
// No error; `HasWrongIsEmpty` does not have `.is_empty()`.
println!("Or this!");
}
}

fn test_slice(b: &[u8]) {
if !b.is_empty() {}
}
Oops, something went wrong.
ProTip! Use n and p to navigate between commits in a pull request.
You can’t perform that action at this time.