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use crate::diagnostic::IntoDiagnosticArg;
use crate::{
Diagnostic, DiagnosticId, DiagnosticMessage, DiagnosticStyledString, ErrorGuaranteed,
ExplicitBug, SubdiagnosticMessage,
};
use crate::{Handler, Level, MultiSpan, StashKey};
use rustc_lint_defs::Applicability;
use rustc_span::source_map::Spanned;
use rustc_span::Span;
use std::borrow::Cow;
use std::fmt::{self, Debug};
use std::marker::PhantomData;
use std::ops::{Deref, DerefMut};
use std::panic;
use std::thread::panicking;
/// Trait implemented by error types. This should not be implemented manually. Instead, use
/// `#[derive(Diagnostic)]` -- see [rustc_macros::Diagnostic].
#[rustc_diagnostic_item = "IntoDiagnostic"]
pub trait IntoDiagnostic<'a, T: EmissionGuarantee = ErrorGuaranteed> {
/// Write out as a diagnostic out of `Handler`.
#[must_use]
fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, T>;
}
impl<'a, T, E> IntoDiagnostic<'a, E> for Spanned<T>
where
T: IntoDiagnostic<'a, E>,
E: EmissionGuarantee,
{
fn into_diagnostic(self, handler: &'a Handler) -> DiagnosticBuilder<'a, E> {
let mut diag = self.node.into_diagnostic(handler);
diag.set_span(self.span);
diag
}
}
/// Used for emitting structured error messages and other diagnostic information.
///
/// If there is some state in a downstream crate you would like to
/// access in the methods of `DiagnosticBuilder` here, consider
/// extending `HandlerFlags`, accessed via `self.handler.flags`.
#[must_use]
#[derive(Clone)]
pub struct DiagnosticBuilder<'a, G: EmissionGuarantee> {
inner: DiagnosticBuilderInner<'a>,
_marker: PhantomData<G>,
}
/// This type exists only for `DiagnosticBuilder::forget_guarantee`, because it:
/// 1. lacks the `G` parameter and therefore `DiagnosticBuilder<G1>` can be
/// converted into `DiagnosticBuilder<G2>` while reusing the `inner` field
/// 2. can implement the `Drop` "bomb" instead of `DiagnosticBuilder`, as it
/// contains all of the data (`state` + `diagnostic`) of `DiagnosticBuilder`
///
/// The `diagnostic` field is not `Copy` and can't be moved out of whichever
/// type implements the `Drop` "bomb", but because of the above two facts, that
/// never needs to happen - instead, the whole `inner: DiagnosticBuilderInner`
/// can be moved out of a `DiagnosticBuilder` and into another.
#[must_use]
#[derive(Clone)]
struct DiagnosticBuilderInner<'a> {
state: DiagnosticBuilderState<'a>,
/// `Diagnostic` is a large type, and `DiagnosticBuilder` is often used as a
/// return value, especially within the frequently-used `PResult` type.
/// In theory, return value optimization (RVO) should avoid unnecessary
/// copying. In practice, it does not (at the time of writing).
diagnostic: Box<Diagnostic>,
}
#[derive(Clone)]
enum DiagnosticBuilderState<'a> {
/// Initial state of a `DiagnosticBuilder`, before `.emit()` or `.cancel()`.
///
/// The `Diagnostic` will be emitted through this `Handler`.
Emittable(&'a Handler),
/// State of a `DiagnosticBuilder`, after `.emit()` or *during* `.cancel()`.
///
/// The `Diagnostic` will be ignored when calling `.emit()`, and it can be
/// assumed that `.emit()` was previously called, to end up in this state.
///
/// While this is also used by `.cancel()`, this state is only observed by
/// the `Drop` `impl` of `DiagnosticBuilderInner`, as `.cancel()` takes
/// `self` by-value specifically to prevent any attempts to `.emit()`.
///
// FIXME(eddyb) currently this doesn't prevent extending the `Diagnostic`,
// despite that being potentially lossy, if important information is added
// *after* the original `.emit()` call.
AlreadyEmittedOrDuringCancellation,
}
// `DiagnosticBuilderState` should be pointer-sized.
rustc_data_structures::static_assert_size!(
DiagnosticBuilderState<'_>,
std::mem::size_of::<&Handler>()
);
/// Trait for types that `DiagnosticBuilder::emit` can return as a "guarantee"
/// (or "proof") token that the emission happened.
pub trait EmissionGuarantee: Sized {
/// Implementation of `DiagnosticBuilder::emit`, fully controlled by each
/// `impl` of `EmissionGuarantee`, to make it impossible to create a value
/// of `Self` without actually performing the emission.
#[track_caller]
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self;
/// Creates a new `DiagnosticBuilder` that will return this type of guarantee.
#[track_caller]
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self>;
}
impl<'a> DiagnosticBuilder<'a, ErrorGuaranteed> {
/// Convenience function for internal use, clients should use one of the
/// `struct_*` methods on [`Handler`].
#[track_caller]
pub(crate) fn new_guaranteeing_error<M: Into<DiagnosticMessage>>(
handler: &'a Handler,
message: M,
) -> Self {
Self {
inner: DiagnosticBuilderInner {
state: DiagnosticBuilderState::Emittable(handler),
diagnostic: Box::new(Diagnostic::new_with_code(
Level::Error { lint: false },
None,
message,
)),
},
_marker: PhantomData,
}
}
/// Discard the guarantee `.emit()` would return, in favor of having the
/// type `DiagnosticBuilder<'a, ()>`. This may be necessary whenever there
/// is a common codepath handling both errors and warnings.
pub fn forget_guarantee(self) -> DiagnosticBuilder<'a, ()> {
DiagnosticBuilder { inner: self.inner, _marker: PhantomData }
}
}
// FIXME(eddyb) make `ErrorGuaranteed` impossible to create outside `.emit()`.
impl EmissionGuarantee for ErrorGuaranteed {
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self {
match db.inner.state {
// First `.emit()` call, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => {
db.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
let guar = handler.emit_diagnostic(&mut db.inner.diagnostic);
// Only allow a guarantee if the `level` wasn't switched to a
// non-error - the field isn't `pub`, but the whole `Diagnostic`
// can be overwritten with a new one, thanks to `DerefMut`.
assert!(
db.inner.diagnostic.is_error(),
"emitted non-error ({:?}) diagnostic \
from `DiagnosticBuilder<ErrorGuaranteed>`",
db.inner.diagnostic.level,
);
guar.unwrap()
}
// `.emit()` was previously called, disallowed from repeating it,
// but can take advantage of the previous `.emit()`'s guarantee
// still being applicable (i.e. as a form of idempotency).
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {
// Only allow a guarantee if the `level` wasn't switched to a
// non-error - the field isn't `pub`, but the whole `Diagnostic`
// can be overwritten with a new one, thanks to `DerefMut`.
assert!(
db.inner.diagnostic.is_error(),
"`DiagnosticBuilder<ErrorGuaranteed>`'s diagnostic \
became non-error ({:?}), after original `.emit()`",
db.inner.diagnostic.level,
);
#[allow(deprecated)]
ErrorGuaranteed::unchecked_claim_error_was_emitted()
}
}
}
#[track_caller]
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self> {
DiagnosticBuilder::new_guaranteeing_error(handler, msg)
}
}
impl<'a> DiagnosticBuilder<'a, ()> {
/// Convenience function for internal use, clients should use one of the
/// `struct_*` methods on [`Handler`].
#[track_caller]
pub(crate) fn new<M: Into<DiagnosticMessage>>(
handler: &'a Handler,
level: Level,
message: M,
) -> Self {
let diagnostic = Diagnostic::new_with_code(level, None, message);
Self::new_diagnostic(handler, diagnostic)
}
/// Creates a new `DiagnosticBuilder` with an already constructed
/// diagnostic.
#[track_caller]
pub(crate) fn new_diagnostic(handler: &'a Handler, diagnostic: Diagnostic) -> Self {
debug!("Created new diagnostic");
Self {
inner: DiagnosticBuilderInner {
state: DiagnosticBuilderState::Emittable(handler),
diagnostic: Box::new(diagnostic),
},
_marker: PhantomData,
}
}
}
// FIXME(eddyb) should there be a `Option<ErrorGuaranteed>` impl as well?
impl EmissionGuarantee for () {
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self {
match db.inner.state {
// First `.emit()` call, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => {
db.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
handler.emit_diagnostic(&mut db.inner.diagnostic);
}
// `.emit()` was previously called, disallowed from repeating it.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {}
}
}
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self> {
DiagnosticBuilder::new(handler, Level::Warning(None), msg)
}
}
/// Marker type which enables implementation of `create_note` and `emit_note` functions for
/// note-without-error struct diagnostics.
#[derive(Copy, Clone)]
pub struct Noted;
impl<'a> DiagnosticBuilder<'a, Noted> {
/// Convenience function for internal use, clients should use one of the
/// `struct_*` methods on [`Handler`].
pub(crate) fn new_note(handler: &'a Handler, message: impl Into<DiagnosticMessage>) -> Self {
let diagnostic = Diagnostic::new_with_code(Level::Note, None, message);
Self::new_diagnostic_note(handler, diagnostic)
}
/// Creates a new `DiagnosticBuilder` with an already constructed
/// diagnostic.
pub(crate) fn new_diagnostic_note(handler: &'a Handler, diagnostic: Diagnostic) -> Self {
debug!("Created new diagnostic");
Self {
inner: DiagnosticBuilderInner {
state: DiagnosticBuilderState::Emittable(handler),
diagnostic: Box::new(diagnostic),
},
_marker: PhantomData,
}
}
}
impl EmissionGuarantee for Noted {
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self {
match db.inner.state {
// First `.emit()` call, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => {
db.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
handler.emit_diagnostic(&mut db.inner.diagnostic);
}
// `.emit()` was previously called, disallowed from repeating it.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {}
}
Noted
}
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self> {
DiagnosticBuilder::new_note(handler, msg)
}
}
/// Marker type which enables implementation of `create_bug` and `emit_bug` functions for
/// bug struct diagnostics.
#[derive(Copy, Clone)]
pub struct Bug;
impl<'a> DiagnosticBuilder<'a, Bug> {
/// Convenience function for internal use, clients should use one of the
/// `struct_*` methods on [`Handler`].
#[track_caller]
pub(crate) fn new_bug(handler: &'a Handler, message: impl Into<DiagnosticMessage>) -> Self {
let diagnostic = Diagnostic::new_with_code(Level::Bug, None, message);
Self::new_diagnostic_bug(handler, diagnostic)
}
/// Creates a new `DiagnosticBuilder` with an already constructed
/// diagnostic.
pub(crate) fn new_diagnostic_bug(handler: &'a Handler, diagnostic: Diagnostic) -> Self {
debug!("Created new diagnostic bug");
Self {
inner: DiagnosticBuilderInner {
state: DiagnosticBuilderState::Emittable(handler),
diagnostic: Box::new(diagnostic),
},
_marker: PhantomData,
}
}
}
impl EmissionGuarantee for Bug {
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self {
match db.inner.state {
// First `.emit()` call, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => {
db.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
handler.emit_diagnostic(&mut db.inner.diagnostic);
}
// `.emit()` was previously called, disallowed from repeating it.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {}
}
// Then panic. No need to return the marker type.
panic::panic_any(ExplicitBug);
}
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self> {
DiagnosticBuilder::new_bug(handler, msg)
}
}
impl<'a> DiagnosticBuilder<'a, !> {
/// Convenience function for internal use, clients should use one of the
/// `struct_*` methods on [`Handler`].
#[track_caller]
pub(crate) fn new_fatal(handler: &'a Handler, message: impl Into<DiagnosticMessage>) -> Self {
let diagnostic = Diagnostic::new_with_code(Level::Fatal, None, message);
Self::new_diagnostic_fatal(handler, diagnostic)
}
/// Creates a new `DiagnosticBuilder` with an already constructed
/// diagnostic.
pub(crate) fn new_diagnostic_fatal(handler: &'a Handler, diagnostic: Diagnostic) -> Self {
debug!("Created new diagnostic");
Self {
inner: DiagnosticBuilderInner {
state: DiagnosticBuilderState::Emittable(handler),
diagnostic: Box::new(diagnostic),
},
_marker: PhantomData,
}
}
}
impl EmissionGuarantee for ! {
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self {
match db.inner.state {
// First `.emit()` call, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => {
db.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
handler.emit_diagnostic(&mut db.inner.diagnostic);
}
// `.emit()` was previously called, disallowed from repeating it.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {}
}
// Then fatally error, returning `!`
crate::FatalError.raise()
}
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self> {
DiagnosticBuilder::new_fatal(handler, msg)
}
}
impl<'a> DiagnosticBuilder<'a, rustc_span::fatal_error::FatalError> {
/// Convenience function for internal use, clients should use one of the
/// `struct_*` methods on [`Handler`].
#[track_caller]
pub(crate) fn new_almost_fatal(
handler: &'a Handler,
message: impl Into<DiagnosticMessage>,
) -> Self {
let diagnostic = Diagnostic::new_with_code(Level::Fatal, None, message);
Self::new_diagnostic_almost_fatal(handler, diagnostic)
}
/// Creates a new `DiagnosticBuilder` with an already constructed
/// diagnostic.
pub(crate) fn new_diagnostic_almost_fatal(
handler: &'a Handler,
diagnostic: Diagnostic,
) -> Self {
debug!("Created new diagnostic");
Self {
inner: DiagnosticBuilderInner {
state: DiagnosticBuilderState::Emittable(handler),
diagnostic: Box::new(diagnostic),
},
_marker: PhantomData,
}
}
}
impl EmissionGuarantee for rustc_span::fatal_error::FatalError {
fn diagnostic_builder_emit_producing_guarantee(db: &mut DiagnosticBuilder<'_, Self>) -> Self {
match db.inner.state {
// First `.emit()` call, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => {
db.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
handler.emit_diagnostic(&mut db.inner.diagnostic);
}
// `.emit()` was previously called, disallowed from repeating it.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {}
}
// Then fatally error..
rustc_span::fatal_error::FatalError
}
fn make_diagnostic_builder(
handler: &Handler,
msg: impl Into<DiagnosticMessage>,
) -> DiagnosticBuilder<'_, Self> {
DiagnosticBuilder::new_almost_fatal(handler, msg)
}
}
/// In general, the `DiagnosticBuilder` uses deref to allow access to
/// the fields and methods of the embedded `diagnostic` in a
/// transparent way. *However,* many of the methods are intended to
/// be used in a chained way, and hence ought to return `self`. In
/// that case, we can't just naively forward to the method on the
/// `diagnostic`, because the return type would be a `&Diagnostic`
/// instead of a `&DiagnosticBuilder<'a>`. This `forward!` macro makes
/// it easy to declare such methods on the builder.
macro_rules! forward {
// Forward pattern for &mut self -> &mut Self
(
$(#[$attrs:meta])*
pub fn $n:ident(&mut self, $($name:ident: $ty:ty),* $(,)?) -> &mut Self
) => {
$(#[$attrs])*
#[doc = concat!("See [`Diagnostic::", stringify!($n), "()`].")]
pub fn $n(&mut self, $($name: $ty),*) -> &mut Self {
self.inner.diagnostic.$n($($name),*);
self
}
};
}
impl<G: EmissionGuarantee> Deref for DiagnosticBuilder<'_, G> {
type Target = Diagnostic;
fn deref(&self) -> &Diagnostic {
&self.inner.diagnostic
}
}
impl<G: EmissionGuarantee> DerefMut for DiagnosticBuilder<'_, G> {
fn deref_mut(&mut self) -> &mut Diagnostic {
&mut self.inner.diagnostic
}
}
impl<'a, G: EmissionGuarantee> DiagnosticBuilder<'a, G> {
/// Emit the diagnostic.
#[track_caller]
pub fn emit(&mut self) -> G {
G::diagnostic_builder_emit_producing_guarantee(self)
}
/// Emit the diagnostic unless `delay` is true,
/// in which case the emission will be delayed as a bug.
///
/// See `emit` and `delay_as_bug` for details.
#[track_caller]
pub fn emit_unless(&mut self, delay: bool) -> G {
if delay {
self.downgrade_to_delayed_bug();
}
self.emit()
}
/// Cancel the diagnostic (a structured diagnostic must either be emitted or
/// cancelled or it will panic when dropped).
///
/// This method takes `self` by-value to disallow calling `.emit()` on it,
/// which may be expected to *guarantee* the emission of an error, either
/// at the time of the call, or through a prior `.emit()` call.
pub fn cancel(mut self) {
self.inner.state = DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation;
drop(self);
}
/// Stashes diagnostic for possible later improvement in a different,
/// later stage of the compiler. The diagnostic can be accessed with
/// the provided `span` and `key` through [`Handler::steal_diagnostic()`].
///
/// As with `buffer`, this is unless the handler has disabled such buffering.
pub fn stash(self, span: Span, key: StashKey) {
if let Some((diag, handler)) = self.into_diagnostic() {
handler.stash_diagnostic(span, key, diag);
}
}
/// Converts the builder to a `Diagnostic` for later emission,
/// unless handler has disabled such buffering, or `.emit()` was called.
pub fn into_diagnostic(mut self) -> Option<(Diagnostic, &'a Handler)> {
let handler = match self.inner.state {
// No `.emit()` calls, the `&Handler` is still available.
DiagnosticBuilderState::Emittable(handler) => handler,
// `.emit()` was previously called, nothing we can do.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {
return None;
}
};
if handler.inner.lock().flags.dont_buffer_diagnostics
|| handler.inner.lock().flags.treat_err_as_bug.is_some()
{
self.emit();
return None;
}
// Take the `Diagnostic` by replacing it with a dummy.
let dummy = Diagnostic::new(Level::Allow, DiagnosticMessage::from(""));
let diagnostic = std::mem::replace(&mut *self.inner.diagnostic, dummy);
// Disable the ICE on `Drop`.
self.cancel();
// Logging here is useful to help track down where in logs an error was
// actually emitted.
debug!("buffer: diagnostic={:?}", diagnostic);
Some((diagnostic, handler))
}
/// Retrieves the [`Handler`] if available
pub fn handler(&self) -> Option<&Handler> {
match self.inner.state {
DiagnosticBuilderState::Emittable(handler) => Some(handler),
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => None,
}
}
/// Buffers the diagnostic for later emission,
/// unless handler has disabled such buffering.
pub fn buffer(self, buffered_diagnostics: &mut Vec<Diagnostic>) {
buffered_diagnostics.extend(self.into_diagnostic().map(|(diag, _)| diag));
}
/// Delay emission of this diagnostic as a bug.
///
/// This can be useful in contexts where an error indicates a bug but
/// typically this only happens when other compilation errors have already
/// happened. In those cases this can be used to defer emission of this
/// diagnostic as a bug in the compiler only if no other errors have been
/// emitted.
///
/// In the meantime, though, callsites are required to deal with the "bug"
/// locally in whichever way makes the most sense.
#[track_caller]
pub fn delay_as_bug(&mut self) -> G {
self.downgrade_to_delayed_bug();
self.emit()
}
forward!(
#[track_caller]
pub fn downgrade_to_delayed_bug(&mut self,) -> &mut Self
);
forward!(
/// Appends a labeled span to the diagnostic.
///
/// Labels are used to convey additional context for the diagnostic's primary span. They will
/// be shown together with the original diagnostic's span, *not* with spans added by
/// `span_note`, `span_help`, etc. Therefore, if the primary span is not displayable (because
/// the span is `DUMMY_SP` or the source code isn't found), labels will not be displayed
/// either.
///
/// Implementation-wise, the label span is pushed onto the [`MultiSpan`] that was created when
/// the diagnostic was constructed. However, the label span is *not* considered a
/// ["primary span"][`MultiSpan`]; only the `Span` supplied when creating the diagnostic is
/// primary.
pub fn span_label(&mut self, span: Span, label: impl Into<SubdiagnosticMessage>) -> &mut Self);
forward!(
/// Labels all the given spans with the provided label.
/// See [`Diagnostic::span_label()`] for more information.
pub fn span_labels(
&mut self,
spans: impl IntoIterator<Item = Span>,
label: &str,
) -> &mut Self);
forward!(pub fn note_expected_found(
&mut self,
expected_label: &dyn fmt::Display,
expected: DiagnosticStyledString,
found_label: &dyn fmt::Display,
found: DiagnosticStyledString,
) -> &mut Self);
forward!(pub fn note_expected_found_extra(
&mut self,
expected_label: &dyn fmt::Display,
expected: DiagnosticStyledString,
found_label: &dyn fmt::Display,
found: DiagnosticStyledString,
expected_extra: &dyn fmt::Display,
found_extra: &dyn fmt::Display,
) -> &mut Self);
forward!(pub fn note_unsuccessful_coercion(
&mut self,
expected: DiagnosticStyledString,
found: DiagnosticStyledString,
) -> &mut Self);
forward!(pub fn note(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self);
forward!(pub fn note_once(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self);
forward!(pub fn span_note(
&mut self,
sp: impl Into<MultiSpan>,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self);
forward!(pub fn span_note_once(
&mut self,
sp: impl Into<MultiSpan>,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self);
forward!(pub fn warn(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self);
forward!(pub fn span_warn(
&mut self,
sp: impl Into<MultiSpan>,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self);
forward!(pub fn help(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self);
forward!(pub fn span_help(
&mut self,
sp: impl Into<MultiSpan>,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self);
forward!(pub fn set_is_lint(&mut self,) -> &mut Self);
forward!(pub fn disable_suggestions(&mut self,) -> &mut Self);
forward!(pub fn clear_suggestions(&mut self,) -> &mut Self);
forward!(pub fn multipart_suggestion(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestion: Vec<(Span, String)>,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn multipart_suggestion_verbose(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestion: Vec<(Span, String)>,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn tool_only_multipart_suggestion(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestion: Vec<(Span, String)>,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn span_suggestion(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn span_suggestions(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestions: impl IntoIterator<Item = String>,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn multipart_suggestions(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestions: impl IntoIterator<Item = Vec<(Span, String)>>,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn span_suggestion_short(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn span_suggestion_verbose(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn span_suggestion_hidden(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn tool_only_span_suggestion(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self);
forward!(pub fn set_primary_message(&mut self, msg: impl Into<DiagnosticMessage>) -> &mut Self);
forward!(pub fn set_span(&mut self, sp: impl Into<MultiSpan>) -> &mut Self);
forward!(pub fn code(&mut self, s: DiagnosticId) -> &mut Self);
forward!(pub fn set_arg(
&mut self,
name: impl Into<Cow<'static, str>>,
arg: impl IntoDiagnosticArg,
) -> &mut Self);
forward!(pub fn subdiagnostic(
&mut self,
subdiagnostic: impl crate::AddToDiagnostic
) -> &mut Self);
}
impl<G: EmissionGuarantee> Debug for DiagnosticBuilder<'_, G> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.inner.diagnostic.fmt(f)
}
}
/// Destructor bomb - a `DiagnosticBuilder` must be either emitted or cancelled
/// or we emit a bug.
impl Drop for DiagnosticBuilderInner<'_> {
fn drop(&mut self) {
match self.state {
// No `.emit()` or `.cancel()` calls.
DiagnosticBuilderState::Emittable(handler) => {
if !panicking() {
handler.emit_diagnostic(&mut Diagnostic::new(
Level::Bug,
DiagnosticMessage::from(
"the following error was constructed but not emitted",
),
));
handler.emit_diagnostic(&mut self.diagnostic);
panic!("error was constructed but not emitted");
}
}
// `.emit()` was previously called, or maybe we're during `.cancel()`.
DiagnosticBuilderState::AlreadyEmittedOrDuringCancellation => {}
}
}
}
#[macro_export]
macro_rules! struct_span_err {
($session:expr, $span:expr, $code:ident, $($message:tt)*) => ({
$session.struct_span_err_with_code(
$span,
format!($($message)*),
$crate::error_code!($code),
)
})
}
#[macro_export]
macro_rules! error_code {
($code:ident) => {{ $crate::DiagnosticId::Error(stringify!($code).to_owned()) }};
}