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#![warn(clippy::recursive_format_impl)]
#![allow(
clippy::borrow_deref_ref,
clippy::deref_addrof,
clippy::inherent_to_string_shadow_display,
clippy::to_string_in_format_args,
clippy::uninlined_format_args
)]
use std::fmt;
struct A;
impl A {
fn fmt(&self) {
self.to_string();
}
}
trait B {
fn fmt(&self) {}
}
impl B for A {
fn fmt(&self) {
self.to_string();
}
}
impl fmt::Display for A {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", self.to_string())
}
}
fn fmt(a: A) {
a.to_string();
}
struct C;
impl C {
// Doesn't trigger if to_string defined separately
// i.e. not using ToString trait (from Display)
fn to_string(&self) -> String {
String::from("I am C")
}
}
impl fmt::Display for C {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", self.to_string())
}
}
enum D {
E(String),
F,
}
impl std::fmt::Display for D {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match &self {
Self::E(string) => write!(f, "E {}", string.to_string()),
Self::F => write!(f, "F"),
}
}
}
// Check for use of self as Display, in Display impl
// Triggers on direct use of self
struct G;
impl std::fmt::Display for G {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", self)
}
}
// Triggers on reference to self
struct H;
impl std::fmt::Display for H {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", &self)
}
}
impl std::fmt::Debug for H {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{:?}", &self)
}
}
// Triggers on multiple reference to self
struct H2;
impl std::fmt::Display for H2 {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "{}", &&&self)
}
}
// Doesn't trigger on correct deref
struct I;
impl std::ops::Deref for I {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for I {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", &**self)
}
}
impl std::fmt::Debug for I {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{:?}", &**self)
}
}
// Doesn't trigger on multiple correct deref
struct I2;
impl std::ops::Deref for I2 {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for I2 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", **&&&**self)
}
}
// Doesn't trigger on multiple correct deref
struct I3;
impl std::ops::Deref for I3 {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for I3 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", &&**&&&**self)
}
}
// Does trigger when deref resolves to self
struct J;
impl std::ops::Deref for J {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for J {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", &*self)
}
}
impl std::fmt::Debug for J {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{:?}", &*self)
}
}
struct J2;
impl std::ops::Deref for J2 {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for J2 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", *self)
}
}
struct J3;
impl std::ops::Deref for J3 {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for J3 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", **&&*self)
}
}
struct J4;
impl std::ops::Deref for J4 {
type Target = str;
fn deref(&self) -> &Self::Target {
"test"
}
}
impl std::fmt::Display for J4 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", &&**&&*self)
}
}
// Doesn't trigger on Debug from Display
struct K;
impl std::fmt::Debug for K {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "test")
}
}
impl std::fmt::Display for K {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{:?}", self)
}
}
// Doesn't trigger on Display from Debug
struct K2;
impl std::fmt::Debug for K2 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{}", self)
}
}
impl std::fmt::Display for K2 {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "test")
}
}
// Doesn't trigger on struct fields
struct L {
field1: u32,
field2: i32,
}
impl std::fmt::Display for L {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{},{}", self.field1, self.field2)
}
}
impl std::fmt::Debug for L {
fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
write!(f, "{:?},{:?}", self.field1, self.field2)
}
}
// Doesn't trigger on nested enum matching
enum Tree {
Leaf,
Node(Vec<Tree>),
}
impl std::fmt::Display for Tree {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
Tree::Leaf => write!(f, "*"),
Tree::Node(children) => {
write!(f, "(")?;
for child in children.iter() {
write!(f, "{},", child)?;
}
write!(f, ")")
},
}
}
}
impl std::fmt::Debug for Tree {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
Tree::Leaf => write!(f, "*"),
Tree::Node(children) => {
write!(f, "(")?;
for child in children.iter() {
write!(f, "{:?},", child)?;
}
write!(f, ")")
},
}
}
}
fn main() {
let a = A;
a.to_string();
a.fmt();
fmt(a);
let c = C;
c.to_string();
}
|
