Repository: nushell/nushell
File: crates/nu-protocol/src/errors/shell_error/io.rs (Rust)

Code before:
    }

    fn help<'a>(&'a self) -> Option<Box<dyn std::fmt::Display + 'a>> {
        self.path
            .as_ref()
            .map(|path| format!("The error occurred at '{}'", path.display()))
            .map(|s| Box::new(s) as Box<dyn std::fmt::Display>)
    }

    fn labels(&self) -> Option<Box<dyn Iterator<Item = miette::LabeledSpan> + '_>> {
        let span_is_unknown = self.span == Span::unknown();
        let span = match (span_is_unknown, self.location.as_ref()) {
            (true, None) => return None,
            (false, _) => SourceSpan::from(self.span),
            (true, Some(location)) => SourceSpan::new(0.into(), location.len()),
        };

        let label = LabeledSpan::new_with_span(Some(self.kind.to_string()), span);
        Some(Box::new(std::iter::once(label)))
    }

    fn diagnostic_source(&self) -> Option<&dyn Diagnostic> {
        match &self.additional_context {
            Some(ctx) => Some(ctx as &dyn Diagnostic),
            None => None,
        }
    }

    fn source_code(&self) -> Option<&dyn miette::SourceCode> {
        let span_is_unknown = self.span == Span::unknown();
        match (span_is_unknown, self.location.as_ref()) {
            (true, None) | (false, _) => None,
            (true, Some(location)) => Some(location as &dyn miette::SourceCode),
        }
    }
}

impl From<IoError> for ShellError {
    fn from(value: IoError) -> Self {
        ShellError::Io(value)
    }
}

impl From<IoError> for std::io::Error {
    fn from(value: IoError) -> Self {
        Self::new(value.kind.into(), value)
    }
}

impl From<std::io::ErrorKind> for ErrorKind {
    fn from(value: std::io::ErrorKind) -> Self {

Review comment (suggestion):
At this point, you don't need to match anymore
```suggestion
        self.additional_context.as_ref().map(|ctx| ctx as &dyn Diagnostic)
```

Code after:
            .map(|s| Box::new(s) as Box<dyn std::fmt::Display>)
    }

    fn labels(&self) -> Option<Box<dyn Iterator<Item = miette::LabeledSpan> + '_>> {
        let span_is_unknown = self.span == Span::unknown();
        let span = match (span_is_unknown, self.location.as_ref()) {
            (true, None) => return None,
            (false, _) => SourceSpan::from(self.span),
            (true, Some(location)) => SourceSpan::new(0.into(), location.len()),
        };

        let label = LabeledSpan::new_with_span(Some(self.kind.to_string()), span);
        Some(Box::new(std::iter::once(label)))
    }

    fn diagnostic_source(&self) -> Option<&dyn Diagnostic> {
        self.additional_context
            .as_ref()
            .map(|ctx| ctx as &dyn Diagnostic)
    }

    fn source_code(&self) -> Option<&dyn miette::SourceCode> {
        let span_is_unknown = self.span == Span::unknown();
        match (span_is_unknown, self.location.as_ref()) {
            (true, None) | (false, _) => None,
            (true, Some(location)) => Some(location as &dyn miette::SourceCode),
        }
    }
}

impl From<IoError> for ShellError {
    fn from(value: IoError) -> Self {
        ShellError::Io(value)
    }
}

impl From<IoError> for std::io::Error {
    fn from(value: IoError) -> Self {
        Self::new(value.kind.into(), value)
    }
}

impl From<std::io::ErrorKind> for ErrorKind {
    fn from(value: std::io::ErrorKind) -> Self {
        ErrorKind::Std(value)
    }
}

impl From<ErrorKind> for std::io::ErrorKind {
    fn from(value: ErrorKind) -> Self {
        match value {