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|
// run-rustfix
// aux-build:macro_rules.rs
#![deny(clippy::try_err)]
#![allow(clippy::unnecessary_wraps, clippy::needless_question_mark)]
#[macro_use]
extern crate macro_rules;
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 {
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 {
Err(err)?;
}
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 {
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 {
Err(err)?;
}
Ok(i)
})
.next()
.unwrap();
Ok(res?)
}
fn nested_error() -> Result<i32, i32> {
Ok(1)
}
// Bad suggestion when in macro (see #6242)
macro_rules! try_validation {
($e: expr) => {{
match $e {
Ok(_) => 0,
Err(_) => Err(1)?,
}
}};
}
macro_rules! ret_one {
() => {
1
};
}
macro_rules! try_validation_in_macro {
($e: expr) => {{
match $e {
Ok(_) => 0,
Err(_) => Err(ret_one!())?,
}
}};
}
fn calling_macro() -> Result<i32, i32> {
// macro
try_validation!(Ok::<_, i32>(5));
// `Err` arg is another macro
try_validation_in_macro!(Ok::<_, i32>(5));
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
try_err!();
}
macro_rules! bar {
() => {
String::from("aasdfasdfasdfa")
};
}
macro_rules! foo {
() => {
bar!()
};
}
pub fn macro_inside(fail: bool) -> Result<i32, String> {
if fail {
Err(foo!())?;
}
Ok(0)
}
pub fn poll_write(n: usize) -> Poll<io::Result<usize>> {
if n == 0 {
Err(io::ErrorKind::WriteZero)?
} else if n == 1 {
Err(io::Error::new(io::ErrorKind::InvalidInput, "error"))?
};
Poll::Ready(Ok(n))
}
pub fn poll_next(ready: bool) -> Poll<Option<io::Result<()>>> {
if !ready {
Err(io::ErrorKind::NotFound)?
}
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)
}
|
