1 #![feature(let_chains)]
3 #![feature(rustc_attrs)]
4 #![feature(type_alias_impl_trait)]
5 #![deny(rustc::untranslatable_diagnostic)]
6 #![deny(rustc::diagnostic_outside_of_impl)]
8 use fluent_bundle::FluentResource;
9 use fluent_syntax::parser::ParserError;
10 use rustc_data_structures::sync::Lrc;
11 use rustc_macros::{fluent_messages, Decodable, Encodable};
14 use std::error::Error;
18 use std::path::{Path, PathBuf};
19 use tracing::{instrument, trace};
21 #[cfg(not(parallel_compiler))]
22 use std::cell::LazyCell as Lazy;
23 #[cfg(parallel_compiler)]
24 use std::sync::LazyLock as Lazy;
26 #[cfg(parallel_compiler)]
27 use intl_memoizer::concurrent::IntlLangMemoizer;
28 #[cfg(not(parallel_compiler))]
29 use intl_memoizer::IntlLangMemoizer;
31 pub use fluent_bundle::{FluentArgs, FluentError, FluentValue};
32 pub use unic_langid::{langid, LanguageIdentifier};
34 // Generates `DEFAULT_LOCALE_RESOURCES` static and `fluent_generated` module.
36 ast_lowering => "../locales/en-US/ast_lowering.ftl",
37 ast_passes => "../locales/en-US/ast_passes.ftl",
38 attr => "../locales/en-US/attr.ftl",
39 borrowck => "../locales/en-US/borrowck.ftl",
40 builtin_macros => "../locales/en-US/builtin_macros.ftl",
41 const_eval => "../locales/en-US/const_eval.ftl",
42 driver => "../locales/en-US/driver.ftl",
43 expand => "../locales/en-US/expand.ftl",
44 interface => "../locales/en-US/interface.ftl",
45 infer => "../locales/en-US/infer.ftl",
46 lint => "../locales/en-US/lint.ftl",
47 parser => "../locales/en-US/parser.ftl",
48 passes => "../locales/en-US/passes.ftl",
49 plugin_impl => "../locales/en-US/plugin_impl.ftl",
50 privacy => "../locales/en-US/privacy.ftl",
51 save_analysis => "../locales/en-US/save_analysis.ftl",
52 ty_utils => "../locales/en-US/ty_utils.ftl",
53 typeck => "../locales/en-US/typeck.ftl",
54 mir_dataflow => "../locales/en-US/mir_dataflow.ftl",
57 pub use fluent_generated::{self as fluent, DEFAULT_LOCALE_RESOURCES};
59 pub type FluentBundle = fluent_bundle::bundle::FluentBundle<FluentResource, IntlLangMemoizer>;
61 #[cfg(parallel_compiler)]
62 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
63 FluentBundle::new_concurrent(locales)
66 #[cfg(not(parallel_compiler))]
67 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
68 FluentBundle::new(locales)
72 pub enum TranslationBundleError {
73 /// Failed to read from `.ftl` file.
75 /// Failed to parse contents of `.ftl` file.
76 ParseFtl(ParserError),
77 /// Failed to add `FluentResource` to `FluentBundle`.
78 AddResource(FluentError),
79 /// `$sysroot/share/locale/$locale` does not exist.
81 /// Cannot read directory entries of `$sysroot/share/locale/$locale`.
82 ReadLocalesDir(io::Error),
83 /// Cannot read directory entry of `$sysroot/share/locale/$locale`.
84 ReadLocalesDirEntry(io::Error),
85 /// `$sysroot/share/locale/$locale` is not a directory.
89 impl fmt::Display for TranslationBundleError {
90 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
92 TranslationBundleError::ReadFtl(e) => write!(f, "could not read ftl file: {}", e),
93 TranslationBundleError::ParseFtl(e) => {
94 write!(f, "could not parse ftl file: {}", e)
96 TranslationBundleError::AddResource(e) => write!(f, "failed to add resource: {}", e),
97 TranslationBundleError::MissingLocale => write!(f, "missing locale directory"),
98 TranslationBundleError::ReadLocalesDir(e) => {
99 write!(f, "could not read locales dir: {}", e)
101 TranslationBundleError::ReadLocalesDirEntry(e) => {
102 write!(f, "could not read locales dir entry: {}", e)
104 TranslationBundleError::LocaleIsNotDir => {
105 write!(f, "`$sysroot/share/locales/$locale` is not a directory")
111 impl Error for TranslationBundleError {
112 fn source(&self) -> Option<&(dyn Error + 'static)> {
114 TranslationBundleError::ReadFtl(e) => Some(e),
115 TranslationBundleError::ParseFtl(e) => Some(e),
116 TranslationBundleError::AddResource(e) => Some(e),
117 TranslationBundleError::MissingLocale => None,
118 TranslationBundleError::ReadLocalesDir(e) => Some(e),
119 TranslationBundleError::ReadLocalesDirEntry(e) => Some(e),
120 TranslationBundleError::LocaleIsNotDir => None,
125 impl From<(FluentResource, Vec<ParserError>)> for TranslationBundleError {
126 fn from((_, mut errs): (FluentResource, Vec<ParserError>)) -> Self {
127 TranslationBundleError::ParseFtl(errs.pop().expect("failed ftl parse with no errors"))
131 impl From<Vec<FluentError>> for TranslationBundleError {
132 fn from(mut errs: Vec<FluentError>) -> Self {
133 TranslationBundleError::AddResource(
134 errs.pop().expect("failed adding resource to bundle with no errors"),
139 /// Returns Fluent bundle with the user's locale resources from
140 /// `$sysroot/share/locale/$requested_locale/*.ftl`.
142 /// If `-Z additional-ftl-path` was provided, load that resource and add it to the bundle
143 /// (overriding any conflicting messages).
144 #[instrument(level = "trace")]
145 pub fn fluent_bundle(
146 mut user_provided_sysroot: Option<PathBuf>,
147 mut sysroot_candidates: Vec<PathBuf>,
148 requested_locale: Option<LanguageIdentifier>,
149 additional_ftl_path: Option<&Path>,
150 with_directionality_markers: bool,
151 ) -> Result<Option<Lrc<FluentBundle>>, TranslationBundleError> {
152 if requested_locale.is_none() && additional_ftl_path.is_none() {
156 let fallback_locale = langid!("en-US");
157 let requested_fallback_locale = requested_locale.as_ref() == Some(&fallback_locale);
159 // If there is only `-Z additional-ftl-path`, assume locale is "en-US", otherwise use user
161 let locale = requested_locale.clone().unwrap_or(fallback_locale);
163 let mut bundle = new_bundle(vec![locale]);
165 // Fluent diagnostics can insert directionality isolation markers around interpolated variables
166 // indicating that there may be a shift from right-to-left to left-to-right text (or
167 // vice-versa). These are disabled because they are sometimes visible in the error output, but
168 // may be worth investigating in future (for example: if type names are left-to-right and the
169 // surrounding diagnostic messages are right-to-left, then these might be helpful).
170 bundle.set_use_isolating(with_directionality_markers);
172 // If the user requests the default locale then don't try to load anything.
173 if !requested_fallback_locale && let Some(requested_locale) = requested_locale {
174 let mut found_resources = false;
175 for sysroot in user_provided_sysroot.iter_mut().chain(sysroot_candidates.iter_mut()) {
176 sysroot.push("share");
177 sysroot.push("locale");
178 sysroot.push(requested_locale.to_string());
181 if !sysroot.exists() {
186 if !sysroot.is_dir() {
187 return Err(TranslationBundleError::LocaleIsNotDir);
190 for entry in sysroot.read_dir().map_err(TranslationBundleError::ReadLocalesDir)? {
191 let entry = entry.map_err(TranslationBundleError::ReadLocalesDirEntry)?;
192 let path = entry.path();
194 if path.extension().and_then(|s| s.to_str()) != Some("ftl") {
200 fs::read_to_string(path).map_err(TranslationBundleError::ReadFtl)?;
202 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
204 bundle.add_resource(resource).map_err(TranslationBundleError::from)?;
205 found_resources = true;
209 if !found_resources {
210 return Err(TranslationBundleError::MissingLocale);
214 if let Some(additional_ftl_path) = additional_ftl_path {
216 fs::read_to_string(additional_ftl_path).map_err(TranslationBundleError::ReadFtl)?;
218 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
220 bundle.add_resource_overriding(resource);
223 let bundle = Lrc::new(bundle);
227 /// Type alias for the result of `fallback_fluent_bundle` - a reference-counted pointer to a lazily
228 /// evaluated fluent bundle.
229 pub type LazyFallbackBundle = Lrc<Lazy<FluentBundle, impl FnOnce() -> FluentBundle>>;
231 /// Return the default `FluentBundle` with standard "en-US" diagnostic messages.
232 #[instrument(level = "trace")]
233 pub fn fallback_fluent_bundle(
234 resources: &'static [&'static str],
235 with_directionality_markers: bool,
236 ) -> LazyFallbackBundle {
237 Lrc::new(Lazy::new(move || {
238 let mut fallback_bundle = new_bundle(vec![langid!("en-US")]);
239 // See comment in `fluent_bundle`.
240 fallback_bundle.set_use_isolating(with_directionality_markers);
242 for resource in resources {
243 let resource = FluentResource::try_new(resource.to_string())
244 .expect("failed to parse fallback fluent resource");
246 fallback_bundle.add_resource_overriding(resource);
253 /// Identifier for the Fluent message/attribute corresponding to a diagnostic message.
254 type FluentId = Cow<'static, str>;
256 /// Abstraction over a message in a subdiagnostic (i.e. label, note, help, etc) to support both
257 /// translatable and non-translatable diagnostic messages.
259 /// Translatable messages for subdiagnostics are typically attributes attached to a larger Fluent
260 /// message so messages of this type must be combined with a `DiagnosticMessage` (using
261 /// `DiagnosticMessage::with_subdiagnostic_message`) before rendering. However, subdiagnostics from
262 /// the `SessionSubdiagnostic` derive refer to Fluent identifiers directly.
263 #[rustc_diagnostic_item = "SubdiagnosticMessage"]
264 pub enum SubdiagnosticMessage {
265 /// Non-translatable diagnostic message.
266 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
268 /// Identifier of a Fluent message. Instances of this variant are generated by the
269 /// `SessionSubdiagnostic` derive.
270 FluentIdentifier(FluentId),
271 /// Attribute of a Fluent message. Needs to be combined with a Fluent identifier to produce an
272 /// actual translated message. Instances of this variant are generated by the `fluent_messages`
275 /// <https://projectfluent.org/fluent/guide/attributes.html>
276 FluentAttr(FluentId),
279 /// `From` impl that enables existing diagnostic calls to functions which now take
280 /// `impl Into<SubdiagnosticMessage>` to continue to work as before.
281 impl<S: Into<String>> From<S> for SubdiagnosticMessage {
282 fn from(s: S) -> Self {
283 SubdiagnosticMessage::Str(s.into())
287 /// Abstraction over a message in a diagnostic to support both translatable and non-translatable
288 /// diagnostic messages.
290 /// Intended to be removed once diagnostics are entirely translatable.
291 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
292 #[rustc_diagnostic_item = "DiagnosticMessage"]
293 pub enum DiagnosticMessage {
294 /// Non-translatable diagnostic message.
295 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
297 /// Identifier for a Fluent message (with optional attribute) corresponding to the diagnostic
300 /// <https://projectfluent.org/fluent/guide/hello.html>
301 /// <https://projectfluent.org/fluent/guide/attributes.html>
302 FluentIdentifier(FluentId, Option<FluentId>),
305 impl DiagnosticMessage {
306 /// Given a `SubdiagnosticMessage` which may contain a Fluent attribute, create a new
307 /// `DiagnosticMessage` that combines that attribute with the Fluent identifier of `self`.
309 /// - If the `SubdiagnosticMessage` is non-translatable then return the message as a
310 /// `DiagnosticMessage`.
311 /// - If `self` is non-translatable then return `self`'s message.
312 pub fn with_subdiagnostic_message(&self, sub: SubdiagnosticMessage) -> Self {
313 let attr = match sub {
314 SubdiagnosticMessage::Str(s) => return DiagnosticMessage::Str(s),
315 SubdiagnosticMessage::FluentIdentifier(id) => {
316 return DiagnosticMessage::FluentIdentifier(id, None);
318 SubdiagnosticMessage::FluentAttr(attr) => attr,
322 DiagnosticMessage::Str(s) => DiagnosticMessage::Str(s.clone()),
323 DiagnosticMessage::FluentIdentifier(id, _) => {
324 DiagnosticMessage::FluentIdentifier(id.clone(), Some(attr))
329 /// Returns the `String` contained within the `DiagnosticMessage::Str` variant, assuming that
330 /// this diagnostic message is of the legacy, non-translatable variety. Panics if this
331 /// assumption does not hold.
333 /// Don't use this - it exists to support some places that do comparison with diagnostic
335 pub fn expect_str(&self) -> &str {
337 DiagnosticMessage::Str(s) => s,
338 _ => panic!("expected non-translatable diagnostic message"),
343 /// `From` impl that enables existing diagnostic calls to functions which now take
344 /// `impl Into<DiagnosticMessage>` to continue to work as before.
345 impl<S: Into<String>> From<S> for DiagnosticMessage {
346 fn from(s: S) -> Self {
347 DiagnosticMessage::Str(s.into())
351 /// Translating *into* a subdiagnostic message from a diagnostic message is a little strange - but
352 /// the subdiagnostic functions (e.g. `span_label`) take a `SubdiagnosticMessage` and the
353 /// subdiagnostic derive refers to typed identifiers that are `DiagnosticMessage`s, so need to be
354 /// able to convert between these, as much as they'll be converted back into `DiagnosticMessage`
355 /// using `with_subdiagnostic_message` eventually. Don't use this other than for the derive.
356 impl Into<SubdiagnosticMessage> for DiagnosticMessage {
357 fn into(self) -> SubdiagnosticMessage {
359 DiagnosticMessage::Str(s) => SubdiagnosticMessage::Str(s),
360 DiagnosticMessage::FluentIdentifier(id, None) => {
361 SubdiagnosticMessage::FluentIdentifier(id)
363 // There isn't really a sensible behaviour for this because it loses information but
364 // this is the most sensible of the behaviours.
365 DiagnosticMessage::FluentIdentifier(_, Some(attr)) => {
366 SubdiagnosticMessage::FluentAttr(attr)
372 /// A span together with some additional data.
373 #[derive(Clone, Debug)]
374 pub struct SpanLabel {
375 /// The span we are going to include in the final snippet.
378 /// Is this a primary span? This is the "locus" of the message,
379 /// and is indicated with a `^^^^` underline, versus `----`.
380 pub is_primary: bool,
382 /// What label should we attach to this span (if any)?
383 pub label: Option<DiagnosticMessage>,
386 /// A collection of `Span`s.
388 /// Spans have two orthogonal attributes:
390 /// - They can be *primary spans*. In this case they are the locus of
391 /// the error, and would be rendered with `^^^`.
392 /// - They can have a *label*. In this case, the label is written next
393 /// to the mark in the snippet when we render.
394 #[derive(Clone, Debug, Hash, PartialEq, Eq, Encodable, Decodable)]
395 pub struct MultiSpan {
396 primary_spans: Vec<Span>,
397 span_labels: Vec<(Span, DiagnosticMessage)>,
402 pub fn new() -> MultiSpan {
403 MultiSpan { primary_spans: vec![], span_labels: vec![] }
406 pub fn from_span(primary_span: Span) -> MultiSpan {
407 MultiSpan { primary_spans: vec![primary_span], span_labels: vec![] }
410 pub fn from_spans(mut vec: Vec<Span>) -> MultiSpan {
412 MultiSpan { primary_spans: vec, span_labels: vec![] }
415 pub fn push_span_label(&mut self, span: Span, label: impl Into<DiagnosticMessage>) {
416 self.span_labels.push((span, label.into()));
419 /// Selects the first primary span (if any).
420 pub fn primary_span(&self) -> Option<Span> {
421 self.primary_spans.first().cloned()
424 /// Returns all primary spans.
425 pub fn primary_spans(&self) -> &[Span] {
429 /// Returns `true` if any of the primary spans are displayable.
430 pub fn has_primary_spans(&self) -> bool {
434 /// Returns `true` if this contains only a dummy primary span with any hygienic context.
435 pub fn is_dummy(&self) -> bool {
436 self.primary_spans.iter().all(|sp| sp.is_dummy())
439 /// Replaces all occurrences of one Span with another. Used to move `Span`s in areas that don't
440 /// display well (like std macros). Returns whether replacements occurred.
441 pub fn replace(&mut self, before: Span, after: Span) -> bool {
442 let mut replacements_occurred = false;
443 for primary_span in &mut self.primary_spans {
444 if *primary_span == before {
445 *primary_span = after;
446 replacements_occurred = true;
449 for span_label in &mut self.span_labels {
450 if span_label.0 == before {
451 span_label.0 = after;
452 replacements_occurred = true;
455 replacements_occurred
458 /// Returns the strings to highlight. We always ensure that there
459 /// is an entry for each of the primary spans -- for each primary
460 /// span `P`, if there is at least one label with span `P`, we return
461 /// those labels (marked as primary). But otherwise we return
462 /// `SpanLabel` instances with empty labels.
463 pub fn span_labels(&self) -> Vec<SpanLabel> {
464 let is_primary = |span| self.primary_spans.contains(&span);
466 let mut span_labels = self
469 .map(|&(span, ref label)| SpanLabel {
471 is_primary: is_primary(span),
472 label: Some(label.clone()),
474 .collect::<Vec<_>>();
476 for &span in &self.primary_spans {
477 if !span_labels.iter().any(|sl| sl.span == span) {
478 span_labels.push(SpanLabel { span, is_primary: true, label: None });
485 /// Returns `true` if any of the span labels is displayable.
486 pub fn has_span_labels(&self) -> bool {
487 self.span_labels.iter().any(|(sp, _)| !sp.is_dummy())
491 impl From<Span> for MultiSpan {
492 fn from(span: Span) -> MultiSpan {
493 MultiSpan::from_span(span)
497 impl From<Vec<Span>> for MultiSpan {
498 fn from(spans: Vec<Span>) -> MultiSpan {
499 MultiSpan::from_spans(spans)