typst/src/diag.rs
2020-10-05 15:45:45 +02:00

94 lines
2.6 KiB
Rust

//! Diagnostics for source code.
//!
//! There are no fatal errors. The document will always compile and yield a
//! layout on a best effort process, but diagnostics are nevertheless generated
//! for incorrect things.
use std::fmt::{self, Display, Formatter};
/// A diagnostic that arose in parsing or layouting.
#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
#[cfg_attr(feature = "serialize", derive(serde::Serialize))]
pub struct Diag {
/// How severe / important the diagnostic is.
pub level: Level,
/// A message describing the diagnostic.
pub message: String,
}
/// How severe / important a diagnostic is.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
#[cfg_attr(feature = "serialize", derive(serde::Serialize))]
#[cfg_attr(feature = "serialize", serde(rename_all = "camelCase"))]
pub enum Level {
Warning,
Error,
}
impl Diag {
/// Create a new diagnostic from message and level.
pub fn new(level: Level, message: impl Into<String>) -> Self {
Self { level, message: message.into() }
}
}
impl Display for Level {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
f.pad(match self {
Self::Warning => "warning",
Self::Error => "error",
})
}
}
/// Construct a diagnostic with [`Error`] level.
///
/// ```
/// # use typstc::error;
/// # use typstc::syntax::Span;
/// # let span = Span::ZERO;
/// # let name = "";
/// // Create formatted error values.
/// let error = error!("expected {}", name);
///
/// // Create spanned errors.
/// let spanned = error!(span, "there is an error here");
/// ```
///
/// [`Error`]: diagnostic/enum.Level.html#variant.Error
#[macro_export]
macro_rules! error {
($($tts:tt)*) => {
$crate::__impl_diagnostic!($crate::diag::Level::Error; $($tts)*)
};
}
/// Construct a diagnostic with [`Warning`] level.
///
/// This works exactly like `error!`. See its documentation for more
/// information.
///
/// [`Warning`]: diagnostic/enum.Level.html#variant.Warning
#[macro_export]
macro_rules! warning {
($($tts:tt)*) => {
$crate::__impl_diagnostic!($crate::diag::Level::Warning; $($tts)*)
};
}
/// Backs the `error!` and `warning!` macros.
#[macro_export]
#[doc(hidden)]
macro_rules! __impl_diagnostic {
($level:expr; $fmt:literal $($tts:tt)*) => {
$crate::diag::Diag::new($level, format!($fmt $($tts)*))
};
($level:expr; $span:expr, $fmt:literal $($tts:tt)*) => {
$crate::syntax::Spanned::new(
$crate::__impl_diagnostic!($level; $fmt $($tts)*),
$span,
)
};
}