mirror of https://github.com/rust-lang/rust
201 lines
6.9 KiB
Rust
201 lines
6.9 KiB
Rust
use crate::fmt;
|
|
|
|
/// A struct containing information about the location of a panic.
|
|
///
|
|
/// This structure is created by [`PanicInfo::location()`].
|
|
///
|
|
/// [`PanicInfo::location()`]: crate::panic::PanicInfo::location
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```should_panic
|
|
/// use std::panic;
|
|
///
|
|
/// panic::set_hook(Box::new(|panic_info| {
|
|
/// if let Some(location) = panic_info.location() {
|
|
/// println!("panic occurred in file '{}' at line {}", location.file(), location.line());
|
|
/// } else {
|
|
/// println!("panic occurred but can't get location information...");
|
|
/// }
|
|
/// }));
|
|
///
|
|
/// panic!("Normal panic");
|
|
/// ```
|
|
///
|
|
/// # Comparisons
|
|
///
|
|
/// Comparisons for equality and ordering are made in file, line, then column priority.
|
|
/// Files are compared as strings, not `Path`, which could be unexpected.
|
|
/// See [`Location::file`]'s documentation for more discussion.
|
|
#[lang = "panic_location"]
|
|
#[derive(Copy, Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
|
|
#[stable(feature = "panic_hooks", since = "1.10.0")]
|
|
pub struct Location<'a> {
|
|
file: &'a str,
|
|
line: u32,
|
|
col: u32,
|
|
}
|
|
|
|
impl<'a> Location<'a> {
|
|
/// Returns the source location of the caller of this function. If that function's caller is
|
|
/// annotated then its call location will be returned, and so on up the stack to the first call
|
|
/// within a non-tracked function body.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```
|
|
/// use std::panic::Location;
|
|
///
|
|
/// /// Returns the [`Location`] at which it is called.
|
|
/// #[track_caller]
|
|
/// fn get_caller_location() -> &'static Location<'static> {
|
|
/// Location::caller()
|
|
/// }
|
|
///
|
|
/// /// Returns a [`Location`] from within this function's definition.
|
|
/// fn get_just_one_location() -> &'static Location<'static> {
|
|
/// get_caller_location()
|
|
/// }
|
|
///
|
|
/// let fixed_location = get_just_one_location();
|
|
/// assert_eq!(fixed_location.file(), file!());
|
|
/// assert_eq!(fixed_location.line(), 14);
|
|
/// assert_eq!(fixed_location.column(), 5);
|
|
///
|
|
/// // running the same untracked function in a different location gives us the same result
|
|
/// let second_fixed_location = get_just_one_location();
|
|
/// assert_eq!(fixed_location.file(), second_fixed_location.file());
|
|
/// assert_eq!(fixed_location.line(), second_fixed_location.line());
|
|
/// assert_eq!(fixed_location.column(), second_fixed_location.column());
|
|
///
|
|
/// let this_location = get_caller_location();
|
|
/// assert_eq!(this_location.file(), file!());
|
|
/// assert_eq!(this_location.line(), 28);
|
|
/// assert_eq!(this_location.column(), 21);
|
|
///
|
|
/// // running the tracked function in a different location produces a different value
|
|
/// let another_location = get_caller_location();
|
|
/// assert_eq!(this_location.file(), another_location.file());
|
|
/// assert_ne!(this_location.line(), another_location.line());
|
|
/// assert_ne!(this_location.column(), another_location.column());
|
|
/// ```
|
|
#[must_use]
|
|
#[stable(feature = "track_caller", since = "1.46.0")]
|
|
#[rustc_const_stable(feature = "const_caller_location", since = "1.79.0")]
|
|
#[track_caller]
|
|
#[inline]
|
|
pub const fn caller() -> &'static Location<'static> {
|
|
crate::intrinsics::caller_location()
|
|
}
|
|
|
|
/// Returns the name of the source file from which the panic originated.
|
|
///
|
|
/// # `&str`, not `&Path`
|
|
///
|
|
/// The returned name refers to a source path on the compiling system, but it isn't valid to
|
|
/// represent this directly as a `&Path`. The compiled code may run on a different system with
|
|
/// a different `Path` implementation than the system providing the contents and this library
|
|
/// does not currently have a different "host path" type.
|
|
///
|
|
/// The most surprising behavior occurs when "the same" file is reachable via multiple paths in
|
|
/// the module system (usually using the `#[path = "..."]` attribute or similar), which can
|
|
/// cause what appears to be identical code to return differing values from this function.
|
|
///
|
|
/// # Cross-compilation
|
|
///
|
|
/// This value is not suitable for passing to `Path::new` or similar constructors when the host
|
|
/// platform and target platform differ.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```should_panic
|
|
/// use std::panic;
|
|
///
|
|
/// panic::set_hook(Box::new(|panic_info| {
|
|
/// if let Some(location) = panic_info.location() {
|
|
/// println!("panic occurred in file '{}'", location.file());
|
|
/// } else {
|
|
/// println!("panic occurred but can't get location information...");
|
|
/// }
|
|
/// }));
|
|
///
|
|
/// panic!("Normal panic");
|
|
/// ```
|
|
#[must_use]
|
|
#[stable(feature = "panic_hooks", since = "1.10.0")]
|
|
#[rustc_const_stable(feature = "const_location_fields", since = "1.79.0")]
|
|
#[inline]
|
|
pub const fn file(&self) -> &str {
|
|
self.file
|
|
}
|
|
|
|
/// Returns the line number from which the panic originated.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```should_panic
|
|
/// use std::panic;
|
|
///
|
|
/// panic::set_hook(Box::new(|panic_info| {
|
|
/// if let Some(location) = panic_info.location() {
|
|
/// println!("panic occurred at line {}", location.line());
|
|
/// } else {
|
|
/// println!("panic occurred but can't get location information...");
|
|
/// }
|
|
/// }));
|
|
///
|
|
/// panic!("Normal panic");
|
|
/// ```
|
|
#[must_use]
|
|
#[stable(feature = "panic_hooks", since = "1.10.0")]
|
|
#[rustc_const_stable(feature = "const_location_fields", since = "1.79.0")]
|
|
#[inline]
|
|
pub const fn line(&self) -> u32 {
|
|
self.line
|
|
}
|
|
|
|
/// Returns the column from which the panic originated.
|
|
///
|
|
/// # Examples
|
|
///
|
|
/// ```should_panic
|
|
/// use std::panic;
|
|
///
|
|
/// panic::set_hook(Box::new(|panic_info| {
|
|
/// if let Some(location) = panic_info.location() {
|
|
/// println!("panic occurred at column {}", location.column());
|
|
/// } else {
|
|
/// println!("panic occurred but can't get location information...");
|
|
/// }
|
|
/// }));
|
|
///
|
|
/// panic!("Normal panic");
|
|
/// ```
|
|
#[must_use]
|
|
#[stable(feature = "panic_col", since = "1.25.0")]
|
|
#[rustc_const_stable(feature = "const_location_fields", since = "1.79.0")]
|
|
#[inline]
|
|
pub const fn column(&self) -> u32 {
|
|
self.col
|
|
}
|
|
}
|
|
|
|
#[unstable(
|
|
feature = "panic_internals",
|
|
reason = "internal details of the implementation of the `panic!` and related macros",
|
|
issue = "none"
|
|
)]
|
|
impl<'a> Location<'a> {
|
|
#[doc(hidden)]
|
|
pub const fn internal_constructor(file: &'a str, line: u32, col: u32) -> Self {
|
|
Location { file, line, col }
|
|
}
|
|
}
|
|
|
|
#[stable(feature = "panic_hook_display", since = "1.26.0")]
|
|
impl fmt::Display for Location<'_> {
|
|
fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
|
|
write!(formatter, "{}:{}:{}", self.file, self.line, self.col)
|
|
}
|
|
}
|