localtrace 0.2.0

A local tracing library for Rust
Documentation 
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// SPDX-License-Identifier: MPL-2.0
use core::fmt;

pub type Result<T> = std::result::Result<T, Error>;

#[derive(Debug)]
pub struct Error {
    message: String,
    #[cfg(debug_assertions)]
    backtrace: backtrace::Backtrace,
}

impl Error {
    pub fn new<S>(message: S) -> Self
    where
        S: AsRef<str>,
    {
        Error {
            message: message.as_ref().to_string(),
            #[cfg(debug_assertions)]
            backtrace: backtrace::Backtrace::new(),
        }
    }
}

impl<E> From<E> for Error
where
    E: std::error::Error,
{
    fn from(err: E) -> Self {
        Error::new(err.to_string())
    }
}

impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        writeln!(f, "message: {}", self.message)?;

        #[cfg(debug_assertions)]
        {
            let filter = std::env::var("CARGO_MANIFEST_DIR").unwrap_or_default();
            for frame in self.backtrace.frames() {
                for symbol in frame.symbols() {
                    if let Some(file) = symbol.filename() {
                        {
                            if file.to_string_lossy().starts_with(&filter) {
                                let lineno = symbol.lineno().unwrap_or_default();
                                writeln!(f, "- {}:{}", file.display(), lineno)?;
                            }
                        }
                    }
                }
            }
        }
        Ok(())
    }
}