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#![allow(unused)]
#![warn(clippy::impossible_comparisons)]
#![warn(clippy::redundant_comparisons)]
#![allow(clippy::no_effect)]
#![allow(clippy::short_circuit_statement)]
#![allow(clippy::manual_range_contains)]
const STATUS_BAD_REQUEST: u16 = 400;
const STATUS_SERVER_ERROR: u16 = 500;
struct Status {
code: u16,
}
impl PartialEq<u16> for Status {
fn eq(&self, other: &u16) -> bool {
self.code == *other
}
}
impl PartialOrd<u16> for Status {
fn partial_cmp(&self, other: &u16) -> Option<std::cmp::Ordering> {
self.code.partial_cmp(other)
}
}
impl PartialEq<Status> for u16 {
fn eq(&self, other: &Status) -> bool {
*self == other.code
}
}
impl PartialOrd<Status> for u16 {
fn partial_cmp(&self, other: &Status) -> Option<std::cmp::Ordering> {
self.partial_cmp(&other.code)
}
}
fn main() {
let status_code = 500; // Value doesn't matter for the lint
let status = Status { code: status_code };
// Correct
status_code >= 400 && status_code < 500;
status_code <= 400 && status_code > 500;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `400` < `500`, the expression evaluates to false for any value of `st
status_code > 500 && status_code < 400;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `500` > `400`, the expression evaluates to false for any value of `st
status_code < 500 && status_code > 500;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: `status_code` cannot simultaneously be greater than and less than `500`
// More complex expressions
status_code < { 400 } && status_code > { 500 };
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `{ 400 }` < `{ 500 }`, the expression evaluates to false for any valu
status_code < STATUS_BAD_REQUEST && status_code > STATUS_SERVER_ERROR;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `STATUS_BAD_REQUEST` < `STATUS_SERVER_ERROR`, the expression evaluate
status_code <= u16::MIN + 1 && status_code > STATUS_SERVER_ERROR;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `u16::MIN + 1` < `STATUS_SERVER_ERROR`, the expression evaluates to f
status_code < STATUS_SERVER_ERROR && status_code > STATUS_SERVER_ERROR;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: `status_code` cannot simultaneously be greater than and less than `STATUS_S
// Comparing two different types, via the `impl PartialOrd<u16> for Status`
status < { 400 } && status > { 500 };
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `{ 400 }` < `{ 500 }`, the expression evaluates to false for any valu
status < STATUS_BAD_REQUEST && status > STATUS_SERVER_ERROR;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `STATUS_BAD_REQUEST` < `STATUS_SERVER_ERROR`, the expression evaluate
status <= u16::MIN + 1 && status > STATUS_SERVER_ERROR;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `u16::MIN + 1` < `STATUS_SERVER_ERROR`, the expression evaluates to f
status < STATUS_SERVER_ERROR && status > STATUS_SERVER_ERROR;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: `status` cannot simultaneously be greater than and less than `STATUS_SERVER
// Yoda conditions
// Correct
500 <= status_code && 600 > status_code;
// Correct
500 <= status_code && status_code <= 600;
// Incorrect
500 >= status_code && 600 < status_code;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `500` < `600`, the expression evaluates to false for any value of `st
// Incorrect
500 >= status_code && status_code > 600;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `500` < `600`, the expression evaluates to false for any value of `st
// Yoda conditions, comparing two different types
// Correct
500 <= status && 600 > status;
// Correct
500 <= status && status <= 600;
// Incorrect
500 >= status && 600 < status;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `500` < `600`, the expression evaluates to false for any value of `st
// Incorrect
500 >= status && status > 600;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `500` < `600`, the expression evaluates to false for any value of `st
// Expressions where one of the sides has no effect
status_code < 200 && status_code <= 299;
//~^ ERROR: right-hand side of `&&` operator has no effect
status_code > 200 && status_code >= 299;
//~^ ERROR: left-hand side of `&&` operator has no effect
// Useless left
status_code >= 500 && status_code > 500;
//~^ ERROR: left-hand side of `&&` operator has no effect
// Useless right
status_code > 500 && status_code >= 500;
//~^ ERROR: right-hand side of `&&` operator has no effect
// Useless left
status_code <= 500 && status_code < 500;
//~^ ERROR: left-hand side of `&&` operator has no effect
// Useless right
status_code < 500 && status_code <= 500;
//~^ ERROR: right-hand side of `&&` operator has no effect
// Other types
let name = "Steve";
name < "Jennifer" && name > "Shannon";
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `"Jennifer"` < `"Shannon"`, the expression evaluates to false for any
let numbers = [1, 2];
numbers < [3, 4] && numbers > [5, 6];
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `[3, 4]` < `[5, 6]`, the expression evaluates to false for any value
let letter = 'a';
letter < 'b' && letter > 'c';
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `'b'` < `'c'`, the expression evaluates to false for any value of `le
let area = 42.0;
area < std::f32::consts::E && area > std::f32::consts::PI;
//~^ ERROR: boolean expression will never evaluate to 'true'
//~| NOTE: since `std::f32::consts::E` < `std::f32::consts::PI`, the expression evalua
}
|
