blob: b87eef07fd53a94b3d6284497614d201e42ce3be [file] [log] [blame]
use crate::snippet::Style;
use crate::{
CodeSuggestion, DelayedBugKind, DiagnosticBuilder, DiagnosticMessage, EmissionGuarantee,
ErrCode, Level, MultiSpan, SubdiagnosticMessage, Substitution, SubstitutionPart,
SuggestionStyle,
};
use rustc_data_structures::fx::{FxHashMap, FxIndexMap};
use rustc_error_messages::fluent_value_from_str_list_sep_by_and;
use rustc_error_messages::FluentValue;
use rustc_lint_defs::{Applicability, LintExpectationId};
use rustc_span::symbol::Symbol;
use rustc_span::{Span, DUMMY_SP};
use std::borrow::Cow;
use std::fmt::{self, Debug};
use std::hash::{Hash, Hasher};
use std::panic::Location;
/// Error type for `Diagnostic`'s `suggestions` field, indicating that
/// `.disable_suggestions()` was called on the `Diagnostic`.
#[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
pub struct SuggestionsDisabled;
/// Simplified version of `FluentArg` that can implement `Encodable` and `Decodable`. Collection of
/// `DiagnosticArg` are converted to `FluentArgs` (consuming the collection) at the start of
/// diagnostic emission.
pub type DiagnosticArg<'iter> = (&'iter DiagnosticArgName, &'iter DiagnosticArgValue);
/// Name of a diagnostic argument.
pub type DiagnosticArgName = Cow<'static, str>;
/// Simplified version of `FluentValue` that can implement `Encodable` and `Decodable`. Converted
/// to a `FluentValue` by the emitter to be used in diagnostic translation.
#[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
pub enum DiagnosticArgValue {
Str(Cow<'static, str>),
Number(i128),
StrListSepByAnd(Vec<Cow<'static, str>>),
}
/// Converts a value of a type into a `DiagnosticArg` (typically a field of an `IntoDiagnostic`
/// struct). Implemented as a custom trait rather than `From` so that it is implemented on the type
/// being converted rather than on `DiagnosticArgValue`, which enables types from other `rustc_*`
/// crates to implement this.
pub trait IntoDiagnosticArg {
fn into_diagnostic_arg(self) -> DiagnosticArgValue;
}
impl IntoDiagnosticArg for DiagnosticArgValue {
fn into_diagnostic_arg(self) -> DiagnosticArgValue {
self
}
}
impl Into<FluentValue<'static>> for DiagnosticArgValue {
fn into(self) -> FluentValue<'static> {
match self {
DiagnosticArgValue::Str(s) => From::from(s),
DiagnosticArgValue::Number(n) => From::from(n),
DiagnosticArgValue::StrListSepByAnd(l) => fluent_value_from_str_list_sep_by_and(l),
}
}
}
/// Trait implemented by error types. This should not be implemented manually. Instead, use
/// `#[derive(Subdiagnostic)]` -- see [rustc_macros::Subdiagnostic].
#[rustc_diagnostic_item = "AddToDiagnostic"]
pub trait AddToDiagnostic
where
Self: Sized,
{
/// Add a subdiagnostic to an existing diagnostic.
fn add_to_diagnostic(self, diag: &mut Diagnostic) {
self.add_to_diagnostic_with(diag, |_, m| m);
}
/// Add a subdiagnostic to an existing diagnostic where `f` is invoked on every message used
/// (to optionally perform eager translation).
fn add_to_diagnostic_with<F>(self, diag: &mut Diagnostic, f: F)
where
F: Fn(&mut Diagnostic, SubdiagnosticMessage) -> SubdiagnosticMessage;
}
/// Trait implemented by lint types. This should not be implemented manually. Instead, use
/// `#[derive(LintDiagnostic)]` -- see [rustc_macros::LintDiagnostic].
#[rustc_diagnostic_item = "DecorateLint"]
pub trait DecorateLint<'a, G: EmissionGuarantee> {
/// Decorate and emit a lint.
fn decorate_lint<'b>(self, diag: &'b mut DiagnosticBuilder<'a, G>);
fn msg(&self) -> DiagnosticMessage;
}
#[must_use]
#[derive(Clone, Debug, Encodable, Decodable)]
pub struct Diagnostic {
// NOTE(eddyb) this is private to disallow arbitrary after-the-fact changes,
// outside of what methods in this crate themselves allow.
pub(crate) level: Level,
pub messages: Vec<(DiagnosticMessage, Style)>,
pub code: Option<ErrCode>,
pub span: MultiSpan,
pub children: Vec<SubDiagnostic>,
pub suggestions: Result<Vec<CodeSuggestion>, SuggestionsDisabled>,
args: FxHashMap<DiagnosticArgName, DiagnosticArgValue>,
/// This is not used for highlighting or rendering any error message. Rather, it can be used
/// as a sort key to sort a buffer of diagnostics. By default, it is the primary span of
/// `span` if there is one. Otherwise, it is `DUMMY_SP`.
pub sort_span: Span,
pub is_lint: Option<IsLint>,
/// With `-Ztrack_diagnostics` enabled,
/// we print where in rustc this error was emitted.
pub emitted_at: DiagnosticLocation,
}
#[derive(Clone, Debug, Encodable, Decodable)]
pub struct DiagnosticLocation {
file: Cow<'static, str>,
line: u32,
col: u32,
}
impl DiagnosticLocation {
#[track_caller]
fn caller() -> Self {
let loc = Location::caller();
DiagnosticLocation { file: loc.file().into(), line: loc.line(), col: loc.column() }
}
}
impl fmt::Display for DiagnosticLocation {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "{}:{}:{}", self.file, self.line, self.col)
}
}
#[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
pub struct IsLint {
/// The lint name.
pub(crate) name: String,
/// Indicates whether this lint should show up in cargo's future breakage report.
has_future_breakage: bool,
}
/// A "sub"-diagnostic attached to a parent diagnostic.
/// For example, a note attached to an error.
#[derive(Clone, Debug, PartialEq, Hash, Encodable, Decodable)]
pub struct SubDiagnostic {
pub level: Level,
pub messages: Vec<(DiagnosticMessage, Style)>,
pub span: MultiSpan,
}
#[derive(Debug, PartialEq, Eq)]
pub struct DiagnosticStyledString(pub Vec<StringPart>);
impl DiagnosticStyledString {
pub fn new() -> DiagnosticStyledString {
DiagnosticStyledString(vec![])
}
pub fn push_normal<S: Into<String>>(&mut self, t: S) {
self.0.push(StringPart::Normal(t.into()));
}
pub fn push_highlighted<S: Into<String>>(&mut self, t: S) {
self.0.push(StringPart::Highlighted(t.into()));
}
pub fn push<S: Into<String>>(&mut self, t: S, highlight: bool) {
if highlight {
self.push_highlighted(t);
} else {
self.push_normal(t);
}
}
pub fn normal<S: Into<String>>(t: S) -> DiagnosticStyledString {
DiagnosticStyledString(vec![StringPart::Normal(t.into())])
}
pub fn highlighted<S: Into<String>>(t: S) -> DiagnosticStyledString {
DiagnosticStyledString(vec![StringPart::Highlighted(t.into())])
}
pub fn content(&self) -> String {
self.0.iter().map(|x| x.content()).collect::<String>()
}
}
#[derive(Debug, PartialEq, Eq)]
pub enum StringPart {
Normal(String),
Highlighted(String),
}
impl StringPart {
pub fn content(&self) -> &str {
match self {
&StringPart::Normal(ref s) | &StringPart::Highlighted(ref s) => s,
}
}
}
// Note: most of these methods are setters that return `&mut Self`. The small
// number of simple getter functions all have `get_` prefixes to distinguish
// them from the setters.
impl Diagnostic {
#[track_caller]
pub fn new<M: Into<DiagnosticMessage>>(level: Level, message: M) -> Self {
Diagnostic::new_with_messages(level, vec![(message.into(), Style::NoStyle)])
}
#[track_caller]
pub fn new_with_messages(level: Level, messages: Vec<(DiagnosticMessage, Style)>) -> Self {
Diagnostic {
level,
messages,
code: None,
span: MultiSpan::new(),
children: vec![],
suggestions: Ok(vec![]),
args: Default::default(),
sort_span: DUMMY_SP,
is_lint: None,
emitted_at: DiagnosticLocation::caller(),
}
}
#[inline(always)]
pub fn level(&self) -> Level {
self.level
}
pub fn is_error(&self) -> bool {
match self.level {
Level::Bug
| Level::DelayedBug(DelayedBugKind::Normal)
| Level::Fatal
| Level::Error
| Level::FailureNote => true,
Level::ForceWarning(_)
| Level::Warning
| Level::DelayedBug(DelayedBugKind::GoodPath)
| Level::Note
| Level::OnceNote
| Level::Help
| Level::OnceHelp
| Level::Allow
| Level::Expect(_) => false,
}
}
pub(crate) fn update_unstable_expectation_id(
&mut self,
unstable_to_stable: &FxIndexMap<LintExpectationId, LintExpectationId>,
) {
if let Level::Expect(expectation_id) | Level::ForceWarning(Some(expectation_id)) =
&mut self.level
{
if expectation_id.is_stable() {
return;
}
// The unstable to stable map only maps the unstable `AttrId` to a stable `HirId` with an attribute index.
// The lint index inside the attribute is manually transferred here.
let lint_index = expectation_id.get_lint_index();
expectation_id.set_lint_index(None);
let mut stable_id = unstable_to_stable
.get(expectation_id)
.expect("each unstable `LintExpectationId` must have a matching stable id")
.normalize();
stable_id.set_lint_index(lint_index);
*expectation_id = stable_id;
}
}
/// Indicates whether this diagnostic should show up in cargo's future breakage report.
pub(crate) fn has_future_breakage(&self) -> bool {
matches!(self.is_lint, Some(IsLint { has_future_breakage: true, .. }))
}
pub(crate) fn is_force_warn(&self) -> bool {
match self.level {
Level::ForceWarning(_) => {
assert!(self.is_lint.is_some());
true
}
_ => false,
}
}
/// 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 downgrade_to_delayed_bug(&mut self) {
assert!(
self.is_error(),
"downgrade_to_delayed_bug: cannot downgrade {:?} to DelayedBug: not an error",
self.level
);
self.level = Level::DelayedBug(DelayedBugKind::Normal);
}
/// 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.
#[rustc_lint_diagnostics]
pub fn span_label(&mut self, span: Span, label: impl Into<SubdiagnosticMessage>) -> &mut Self {
self.span.push_span_label(span, self.subdiagnostic_message_to_diagnostic_message(label));
self
}
/// Labels all the given spans with the provided label.
/// See [`Self::span_label()`] for more information.
pub fn span_labels(&mut self, spans: impl IntoIterator<Item = Span>, label: &str) -> &mut Self {
for span in spans {
self.span_label(span, label.to_string());
}
self
}
pub fn replace_span_with(&mut self, after: Span, keep_label: bool) -> &mut Self {
let before = self.span.clone();
self.span(after);
for span_label in before.span_labels() {
if let Some(label) = span_label.label {
if span_label.is_primary && keep_label {
self.span.push_span_label(after, label);
} else {
self.span.push_span_label(span_label.span, label);
}
}
}
self
}
pub fn note_expected_found(
&mut self,
expected_label: &dyn fmt::Display,
expected: DiagnosticStyledString,
found_label: &dyn fmt::Display,
found: DiagnosticStyledString,
) -> &mut Self {
self.note_expected_found_extra(expected_label, expected, found_label, found, &"", &"")
}
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 {
let expected_label = expected_label.to_string();
let expected_label = if expected_label.is_empty() {
"expected".to_string()
} else {
format!("expected {expected_label}")
};
let found_label = found_label.to_string();
let found_label = if found_label.is_empty() {
"found".to_string()
} else {
format!("found {found_label}")
};
let (found_padding, expected_padding) = if expected_label.len() > found_label.len() {
(expected_label.len() - found_label.len(), 0)
} else {
(0, found_label.len() - expected_label.len())
};
let mut msg: Vec<_> =
vec![(format!("{}{} `", " ".repeat(expected_padding), expected_label), Style::NoStyle)];
msg.extend(expected.0.iter().map(|x| match *x {
StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
}));
msg.push((format!("`{expected_extra}\n"), Style::NoStyle));
msg.push((format!("{}{} `", " ".repeat(found_padding), found_label), Style::NoStyle));
msg.extend(found.0.iter().map(|x| match *x {
StringPart::Normal(ref s) => (s.to_owned(), Style::NoStyle),
StringPart::Highlighted(ref s) => (s.to_owned(), Style::Highlight),
}));
msg.push((format!("`{found_extra}"), Style::NoStyle));
// For now, just attach these as notes.
self.highlighted_note(msg);
self
}
pub fn note_trait_signature(&mut self, name: Symbol, signature: String) -> &mut Self {
self.highlighted_note(vec![
(format!("`{name}` from trait: `"), Style::NoStyle),
(signature, Style::Highlight),
("`".to_string(), Style::NoStyle),
]);
self
}
/// Add a note attached to this diagnostic.
#[rustc_lint_diagnostics]
pub fn note(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self {
self.sub(Level::Note, msg, MultiSpan::new());
self
}
fn highlighted_note<M: Into<SubdiagnosticMessage>>(
&mut self,
msg: Vec<(M, Style)>,
) -> &mut Self {
self.sub_with_highlights(Level::Note, msg, MultiSpan::new());
self
}
/// Prints the span with a note above it.
/// This is like [`Diagnostic::note()`], but it gets its own span.
pub fn note_once(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self {
self.sub(Level::OnceNote, msg, MultiSpan::new());
self
}
/// Prints the span with a note above it.
/// This is like [`Diagnostic::note()`], but it gets its own span.
#[rustc_lint_diagnostics]
pub fn span_note<S: Into<MultiSpan>>(
&mut self,
sp: S,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self {
self.sub(Level::Note, msg, sp.into());
self
}
/// Prints the span with a note above it.
/// This is like [`Diagnostic::note()`], but it gets its own span.
pub fn span_note_once<S: Into<MultiSpan>>(
&mut self,
sp: S,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self {
self.sub(Level::OnceNote, msg, sp.into());
self
}
/// Add a warning attached to this diagnostic.
#[rustc_lint_diagnostics]
pub fn warn(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self {
self.sub(Level::Warning, msg, MultiSpan::new());
self
}
/// Prints the span with a warning above it.
/// This is like [`Diagnostic::warn()`], but it gets its own span.
#[rustc_lint_diagnostics]
pub fn span_warn<S: Into<MultiSpan>>(
&mut self,
sp: S,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self {
self.sub(Level::Warning, msg, sp.into());
self
}
/// Add a help message attached to this diagnostic.
#[rustc_lint_diagnostics]
pub fn help(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self {
self.sub(Level::Help, msg, MultiSpan::new());
self
}
/// Prints the span with a help above it.
/// This is like [`Diagnostic::help()`], but it gets its own span.
pub fn help_once(&mut self, msg: impl Into<SubdiagnosticMessage>) -> &mut Self {
self.sub(Level::OnceHelp, msg, MultiSpan::new());
self
}
/// Add a help message attached to this diagnostic with a customizable highlighted message.
pub fn highlighted_help(&mut self, msg: Vec<(String, Style)>) -> &mut Self {
self.sub_with_highlights(Level::Help, msg, MultiSpan::new());
self
}
/// Prints the span with some help above it.
/// This is like [`Diagnostic::help()`], but it gets its own span.
#[rustc_lint_diagnostics]
pub fn span_help<S: Into<MultiSpan>>(
&mut self,
sp: S,
msg: impl Into<SubdiagnosticMessage>,
) -> &mut Self {
self.sub(Level::Help, msg, sp.into());
self
}
/// Disallow attaching suggestions this diagnostic.
/// Any suggestions attached e.g. with the `span_suggestion_*` methods
/// (before and after the call to `disable_suggestions`) will be ignored.
pub fn disable_suggestions(&mut self) -> &mut Self {
self.suggestions = Err(SuggestionsDisabled);
self
}
/// Helper for pushing to `self.suggestions`, if available (not disable).
fn push_suggestion(&mut self, suggestion: CodeSuggestion) {
if let Ok(suggestions) = &mut self.suggestions {
suggestions.push(suggestion);
}
}
/// Show a suggestion that has multiple parts to it.
/// In other words, multiple changes need to be applied as part of this suggestion.
pub fn multipart_suggestion(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestion: Vec<(Span, String)>,
applicability: Applicability,
) -> &mut Self {
self.multipart_suggestion_with_style(
msg,
suggestion,
applicability,
SuggestionStyle::ShowCode,
)
}
/// Show a suggestion that has multiple parts to it, always as it's own subdiagnostic.
/// In other words, multiple changes need to be applied as part of this suggestion.
pub fn multipart_suggestion_verbose(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestion: Vec<(Span, String)>,
applicability: Applicability,
) -> &mut Self {
self.multipart_suggestion_with_style(
msg,
suggestion,
applicability,
SuggestionStyle::ShowAlways,
)
}
/// [`Diagnostic::multipart_suggestion()`] but you can set the [`SuggestionStyle`].
pub fn multipart_suggestion_with_style(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
mut suggestion: Vec<(Span, String)>,
applicability: Applicability,
style: SuggestionStyle,
) -> &mut Self {
suggestion.sort_unstable();
suggestion.dedup();
let parts = suggestion
.into_iter()
.map(|(span, snippet)| SubstitutionPart { snippet, span })
.collect::<Vec<_>>();
assert!(!parts.is_empty());
debug_assert_eq!(
parts.iter().find(|part| part.span.is_empty() && part.snippet.is_empty()),
None,
"Span must not be empty and have no suggestion",
);
debug_assert_eq!(
parts.array_windows().find(|[a, b]| a.span.overlaps(b.span)),
None,
"suggestion must not have overlapping parts",
);
self.push_suggestion(CodeSuggestion {
substitutions: vec![Substitution { parts }],
msg: self.subdiagnostic_message_to_diagnostic_message(msg),
style,
applicability,
});
self
}
/// Prints out a message with for a multipart suggestion without showing the suggested code.
///
/// This is intended to be used for suggestions that are obvious in what the changes need to
/// be from the message, showing the span label inline would be visually unpleasant
/// (marginally overlapping spans or multiline spans) and showing the snippet window wouldn't
/// improve understandability.
pub fn tool_only_multipart_suggestion(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestion: Vec<(Span, String)>,
applicability: Applicability,
) -> &mut Self {
self.multipart_suggestion_with_style(
msg,
suggestion,
applicability,
SuggestionStyle::CompletelyHidden,
)
}
/// Prints out a message with a suggested edit of the code.
///
/// In case of short messages and a simple suggestion, rustc displays it as a label:
///
/// ```text
/// try adding parentheses: `(tup.0).1`
/// ```
///
/// The message
///
/// * should not end in any punctuation (a `:` is added automatically)
/// * should not be a question (avoid language like "did you mean")
/// * should not contain any phrases like "the following", "as shown", etc.
/// * may look like "to do xyz, use" or "to do xyz, use abc"
/// * may contain a name of a function, variable, or type, but not whole expressions
///
/// See `CodeSuggestion` for more information.
pub fn span_suggestion(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self {
self.span_suggestion_with_style(
sp,
msg,
suggestion,
applicability,
SuggestionStyle::ShowCode,
);
self
}
/// [`Diagnostic::span_suggestion()`] but you can set the [`SuggestionStyle`].
pub fn span_suggestion_with_style(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
style: SuggestionStyle,
) -> &mut Self {
debug_assert!(
!(sp.is_empty() && suggestion.to_string().is_empty()),
"Span must not be empty and have no suggestion"
);
self.push_suggestion(CodeSuggestion {
substitutions: vec![Substitution {
parts: vec![SubstitutionPart { snippet: suggestion.to_string(), span: sp }],
}],
msg: self.subdiagnostic_message_to_diagnostic_message(msg),
style,
applicability,
});
self
}
/// Always show the suggested change.
pub fn span_suggestion_verbose(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self {
self.span_suggestion_with_style(
sp,
msg,
suggestion,
applicability,
SuggestionStyle::ShowAlways,
);
self
}
/// Prints out a message with multiple suggested edits of the code.
/// See also [`Diagnostic::span_suggestion()`].
pub fn span_suggestions(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestions: impl IntoIterator<Item = String>,
applicability: Applicability,
) -> &mut Self {
self.span_suggestions_with_style(
sp,
msg,
suggestions,
applicability,
SuggestionStyle::ShowCode,
)
}
/// [`Diagnostic::span_suggestions()`] but you can set the [`SuggestionStyle`].
pub fn span_suggestions_with_style(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestions: impl IntoIterator<Item = String>,
applicability: Applicability,
style: SuggestionStyle,
) -> &mut Self {
let substitutions = suggestions
.into_iter()
.map(|snippet| {
debug_assert!(
!(sp.is_empty() && snippet.is_empty()),
"Span must not be empty and have no suggestion"
);
Substitution { parts: vec![SubstitutionPart { snippet, span: sp }] }
})
.collect();
self.push_suggestion(CodeSuggestion {
substitutions,
msg: self.subdiagnostic_message_to_diagnostic_message(msg),
style,
applicability,
});
self
}
/// Prints out a message with multiple suggested edits of the code, where each edit consists of
/// multiple parts.
/// See also [`Diagnostic::multipart_suggestion()`].
pub fn multipart_suggestions(
&mut self,
msg: impl Into<SubdiagnosticMessage>,
suggestions: impl IntoIterator<Item = Vec<(Span, String)>>,
applicability: Applicability,
) -> &mut Self {
let substitutions = suggestions
.into_iter()
.map(|sugg| {
let mut parts = sugg
.into_iter()
.map(|(span, snippet)| SubstitutionPart { snippet, span })
.collect::<Vec<_>>();
parts.sort_unstable_by_key(|part| part.span);
assert!(!parts.is_empty());
debug_assert_eq!(
parts.iter().find(|part| part.span.is_empty() && part.snippet.is_empty()),
None,
"Span must not be empty and have no suggestion",
);
debug_assert_eq!(
parts.array_windows().find(|[a, b]| a.span.overlaps(b.span)),
None,
"suggestion must not have overlapping parts",
);
Substitution { parts }
})
.collect();
self.push_suggestion(CodeSuggestion {
substitutions,
msg: self.subdiagnostic_message_to_diagnostic_message(msg),
style: SuggestionStyle::ShowCode,
applicability,
});
self
}
/// Prints out a message with a suggested edit of the code. If the suggestion is presented
/// inline, it will only show the message and not the suggestion.
///
/// See `CodeSuggestion` for more information.
pub fn span_suggestion_short(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self {
self.span_suggestion_with_style(
sp,
msg,
suggestion,
applicability,
SuggestionStyle::HideCodeInline,
);
self
}
/// Prints out a message for a suggestion without showing the suggested code.
///
/// This is intended to be used for suggestions that are obvious in what the changes need to
/// be from the message, showing the span label inline would be visually unpleasant
/// (marginally overlapping spans or multiline spans) and showing the snippet window wouldn't
/// improve understandability.
pub fn span_suggestion_hidden(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self {
self.span_suggestion_with_style(
sp,
msg,
suggestion,
applicability,
SuggestionStyle::HideCodeAlways,
);
self
}
/// Adds a suggestion to the JSON output that will not be shown in the CLI.
///
/// This is intended to be used for suggestions that are *very* obvious in what the changes
/// need to be from the message, but we still want other tools to be able to apply them.
#[rustc_lint_diagnostics]
pub fn tool_only_span_suggestion(
&mut self,
sp: Span,
msg: impl Into<SubdiagnosticMessage>,
suggestion: impl ToString,
applicability: Applicability,
) -> &mut Self {
self.span_suggestion_with_style(
sp,
msg,
suggestion,
applicability,
SuggestionStyle::CompletelyHidden,
);
self
}
/// Add a subdiagnostic from a type that implements `Subdiagnostic` (see
/// [rustc_macros::Subdiagnostic]).
pub fn subdiagnostic(&mut self, subdiagnostic: impl AddToDiagnostic) -> &mut Self {
subdiagnostic.add_to_diagnostic(self);
self
}
/// Add a subdiagnostic from a type that implements `Subdiagnostic` (see
/// [rustc_macros::Subdiagnostic]). Performs eager translation of any translatable messages
/// used in the subdiagnostic, so suitable for use with repeated messages (i.e. re-use of
/// interpolated variables).
pub fn eager_subdiagnostic(
&mut self,
dcx: &crate::DiagCtxt,
subdiagnostic: impl AddToDiagnostic,
) -> &mut Self {
subdiagnostic.add_to_diagnostic_with(self, |diag, msg| {
let args = diag.args();
let msg = diag.subdiagnostic_message_to_diagnostic_message(msg);
dcx.eagerly_translate(msg, args)
});
self
}
pub fn span<S: Into<MultiSpan>>(&mut self, sp: S) -> &mut Self {
self.span = sp.into();
if let Some(span) = self.span.primary_span() {
self.sort_span = span;
}
self
}
pub fn is_lint(&mut self, name: String, has_future_breakage: bool) -> &mut Self {
self.is_lint = Some(IsLint { name, has_future_breakage });
self
}
pub fn code(&mut self, code: ErrCode) -> &mut Self {
self.code = Some(code);
self
}
pub fn clear_code(&mut self) -> &mut Self {
self.code = None;
self
}
pub fn get_code(&self) -> Option<ErrCode> {
self.code
}
pub fn primary_message(&mut self, msg: impl Into<DiagnosticMessage>) -> &mut Self {
self.messages[0] = (msg.into(), Style::NoStyle);
self
}
// Exact iteration order of diagnostic arguments shouldn't make a difference to output because
// they're only used in interpolation.
#[allow(rustc::potential_query_instability)]
pub fn args(&self) -> impl Iterator<Item = DiagnosticArg<'_>> {
self.args.iter()
}
pub fn arg(
&mut self,
name: impl Into<Cow<'static, str>>,
arg: impl IntoDiagnosticArg,
) -> &mut Self {
self.args.insert(name.into(), arg.into_diagnostic_arg());
self
}
pub fn replace_args(&mut self, args: FxHashMap<DiagnosticArgName, DiagnosticArgValue>) {
self.args = args;
}
pub fn messages(&self) -> &[(DiagnosticMessage, Style)] {
&self.messages
}
/// Helper function that takes a `SubdiagnosticMessage` and returns a `DiagnosticMessage` by
/// combining it with the primary message of the diagnostic (if translatable, otherwise it just
/// passes the user's string along).
fn subdiagnostic_message_to_diagnostic_message(
&self,
attr: impl Into<SubdiagnosticMessage>,
) -> DiagnosticMessage {
let msg =
self.messages.iter().map(|(msg, _)| msg).next().expect("diagnostic with no messages");
msg.with_subdiagnostic_message(attr.into())
}
/// Convenience function for internal use, clients should use one of the
/// public methods above.
///
/// Used by `proc_macro_server` for implementing `server::Diagnostic`.
pub fn sub(&mut self, level: Level, message: impl Into<SubdiagnosticMessage>, span: MultiSpan) {
let sub = SubDiagnostic {
level,
messages: vec![(
self.subdiagnostic_message_to_diagnostic_message(message),
Style::NoStyle,
)],
span,
};
self.children.push(sub);
}
/// Convenience function for internal use, clients should use one of the
/// public methods above.
fn sub_with_highlights<M: Into<SubdiagnosticMessage>>(
&mut self,
level: Level,
messages: Vec<(M, Style)>,
span: MultiSpan,
) {
let messages = messages
.into_iter()
.map(|m| (self.subdiagnostic_message_to_diagnostic_message(m.0), m.1))
.collect();
let sub = SubDiagnostic { level, messages, span };
self.children.push(sub);
}
/// Fields used for Hash, and PartialEq trait
fn keys(
&self,
) -> (
&Level,
&[(DiagnosticMessage, Style)],
&Option<ErrCode>,
&MultiSpan,
&[SubDiagnostic],
&Result<Vec<CodeSuggestion>, SuggestionsDisabled>,
Vec<(&DiagnosticArgName, &DiagnosticArgValue)>,
&Option<IsLint>,
) {
(
&self.level,
&self.messages,
&self.code,
&self.span,
&self.children,
&self.suggestions,
self.args().collect(),
// omit self.sort_span
&self.is_lint,
// omit self.emitted_at
)
}
}
impl Hash for Diagnostic {
fn hash<H>(&self, state: &mut H)
where
H: Hasher,
{
self.keys().hash(state);
}
}
impl PartialEq for Diagnostic {
fn eq(&self, other: &Self) -> bool {
self.keys() == other.keys()
}
}