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// run-rustfix
// aux-build:proc_macros.rs
#![deny(clippy::try_err)]
#![allow(clippy::unnecessary_wraps, clippy::needless_question_mark)]
extern crate proc_macros;
use proc_macros::{external, inline_macros};
use std::io;
use std::task::Poll;
// Tests that a simple case works
// Should flag `Err(err)?`
pub fn basic_test() -> Result<i32, i32> {
let err: i32 = 1;
// To avoid warnings during rustfix
if true {
return Err(err);
}
Ok(0)
}
// Tests that `.into()` is added when appropriate
pub fn into_test() -> Result<i32, i32> {
let err: u8 = 1;
// To avoid warnings during rustfix
if true {
return Err(err.into());
}
Ok(0)
}
// Tests that tries in general don't trigger the error
pub fn negative_test() -> Result<i32, i32> {
Ok(nested_error()? + 1)
}
// Tests that `.into()` isn't added when the error type
// matches the surrounding closure's return type, even
// when it doesn't match the surrounding function's.
pub fn closure_matches_test() -> Result<i32, i32> {
let res: Result<i32, i8> = Some(1)
.into_iter()
.map(|i| {
let err: i8 = 1;
// To avoid warnings during rustfix
if true {
return Err(err);
}
Ok(i)
})
.next()
.unwrap();
Ok(res?)
}
// Tests that `.into()` isn't added when the error type
// doesn't match the surrounding closure's return type.
pub fn closure_into_test() -> Result<i32, i32> {
let res: Result<i32, i16> = Some(1)
.into_iter()
.map(|i| {
let err: i8 = 1;
// To avoid warnings during rustfix
if true {
return Err(err.into());
}
Ok(i)
})
.next()
.unwrap();
Ok(res?)
}
fn nested_error() -> Result<i32, i32> {
Ok(1)
}
#[inline_macros]
fn calling_macro() -> Result<i32, i32> {
// macro
inline!(
match $(Ok::<_, i32>(5)) {
Ok(_) => 0,
Err(_) => return Err(1),
}
);
// `Err` arg is another macro
inline!(
match $(Ok::<_, i32>(5)) {
Ok(_) => 0,
Err(_) => return Err(inline!(1)),
}
);
Ok(5)
}
fn main() {
basic_test().unwrap();
into_test().unwrap();
negative_test().unwrap();
closure_matches_test().unwrap();
closure_into_test().unwrap();
calling_macro().unwrap();
// We don't want to lint in external macros
external! {
pub fn try_err_fn() -> Result<i32, i32> {
let err: i32 = 1;
// To avoid warnings during rustfix
if true { Err(err)? } else { Ok(2) }
}
}
}
#[inline_macros]
pub fn macro_inside(fail: bool) -> Result<i32, String> {
if fail {
return Err(inline!(inline!(String::from("aasdfasdfasdfa"))));
}
Ok(0)
}
pub fn poll_write(n: usize) -> Poll<io::Result<usize>> {
if n == 0 {
return Poll::Ready(Err(io::ErrorKind::WriteZero.into()))
} else if n == 1 {
return Poll::Ready(Err(io::Error::new(io::ErrorKind::InvalidInput, "error")))
};
Poll::Ready(Ok(n))
}
pub fn poll_next(ready: bool) -> Poll<Option<io::Result<()>>> {
if !ready {
return Poll::Ready(Some(Err(io::ErrorKind::NotFound.into())))
}
Poll::Ready(None)
}
// Tests that `return` is not duplicated
pub fn try_return(x: bool) -> Result<i32, i32> {
if x {
return Err(42);
}
Ok(0)
}
|
