31 lines
694 B
Rust
31 lines
694 B
Rust
#![warn(clippy::map_err_ignore)]
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#![allow(clippy::unnecessary_wraps)]
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use std::error::Error;
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use std::fmt;
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#[derive(Debug)]
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enum Errors {
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Ignored,
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}
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impl Error for Errors {}
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impl fmt::Display for Errors {
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fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
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write!(f, "Error")
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}
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}
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fn main() -> Result<(), Errors> {
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let x = u32::try_from(-123_i32);
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println!("{:?}", x.map_err(|_| Errors::Ignored));
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//~^ ERROR: `map_err(|_|...` wildcard pattern discards the original error
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// Should not warn you because you explicitly ignore the parameter
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// using a named wildcard value
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println!("{:?}", x.map_err(|_foo| Errors::Ignored));
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Ok(())
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}
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