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 session => "../locales/en-US/session.ftl",
45 interface => "../locales/en-US/interface.ftl",
46 infer => "../locales/en-US/infer.ftl",
47 lint => "../locales/en-US/lint.ftl",
48 monomorphize => "../locales/en-US/monomorphize.ftl",
49 parser => "../locales/en-US/parser.ftl",
50 passes => "../locales/en-US/passes.ftl",
51 plugin_impl => "../locales/en-US/plugin_impl.ftl",
52 privacy => "../locales/en-US/privacy.ftl",
53 save_analysis => "../locales/en-US/save_analysis.ftl",
54 ty_utils => "../locales/en-US/ty_utils.ftl",
55 typeck => "../locales/en-US/typeck.ftl",
56 mir_dataflow => "../locales/en-US/mir_dataflow.ftl",
59 pub use fluent_generated::{self as fluent, DEFAULT_LOCALE_RESOURCES};
61 pub type FluentBundle = fluent_bundle::bundle::FluentBundle<FluentResource, IntlLangMemoizer>;
63 #[cfg(parallel_compiler)]
64 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
65 FluentBundle::new_concurrent(locales)
68 #[cfg(not(parallel_compiler))]
69 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
70 FluentBundle::new(locales)
74 pub enum TranslationBundleError {
75 /// Failed to read from `.ftl` file.
77 /// Failed to parse contents of `.ftl` file.
78 ParseFtl(ParserError),
79 /// Failed to add `FluentResource` to `FluentBundle`.
80 AddResource(FluentError),
81 /// `$sysroot/share/locale/$locale` does not exist.
83 /// Cannot read directory entries of `$sysroot/share/locale/$locale`.
84 ReadLocalesDir(io::Error),
85 /// Cannot read directory entry of `$sysroot/share/locale/$locale`.
86 ReadLocalesDirEntry(io::Error),
87 /// `$sysroot/share/locale/$locale` is not a directory.
91 impl fmt::Display for TranslationBundleError {
92 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
94 TranslationBundleError::ReadFtl(e) => write!(f, "could not read ftl file: {}", e),
95 TranslationBundleError::ParseFtl(e) => {
96 write!(f, "could not parse ftl file: {}", e)
98 TranslationBundleError::AddResource(e) => write!(f, "failed to add resource: {}", e),
99 TranslationBundleError::MissingLocale => write!(f, "missing locale directory"),
100 TranslationBundleError::ReadLocalesDir(e) => {
101 write!(f, "could not read locales dir: {}", e)
103 TranslationBundleError::ReadLocalesDirEntry(e) => {
104 write!(f, "could not read locales dir entry: {}", e)
106 TranslationBundleError::LocaleIsNotDir => {
107 write!(f, "`$sysroot/share/locales/$locale` is not a directory")
113 impl Error for TranslationBundleError {
114 fn source(&self) -> Option<&(dyn Error + 'static)> {
116 TranslationBundleError::ReadFtl(e) => Some(e),
117 TranslationBundleError::ParseFtl(e) => Some(e),
118 TranslationBundleError::AddResource(e) => Some(e),
119 TranslationBundleError::MissingLocale => None,
120 TranslationBundleError::ReadLocalesDir(e) => Some(e),
121 TranslationBundleError::ReadLocalesDirEntry(e) => Some(e),
122 TranslationBundleError::LocaleIsNotDir => None,
127 impl From<(FluentResource, Vec<ParserError>)> for TranslationBundleError {
128 fn from((_, mut errs): (FluentResource, Vec<ParserError>)) -> Self {
129 TranslationBundleError::ParseFtl(errs.pop().expect("failed ftl parse with no errors"))
133 impl From<Vec<FluentError>> for TranslationBundleError {
134 fn from(mut errs: Vec<FluentError>) -> Self {
135 TranslationBundleError::AddResource(
136 errs.pop().expect("failed adding resource to bundle with no errors"),
141 /// Returns Fluent bundle with the user's locale resources from
142 /// `$sysroot/share/locale/$requested_locale/*.ftl`.
144 /// If `-Z additional-ftl-path` was provided, load that resource and add it to the bundle
145 /// (overriding any conflicting messages).
146 #[instrument(level = "trace")]
147 pub fn fluent_bundle(
148 mut user_provided_sysroot: Option<PathBuf>,
149 mut sysroot_candidates: Vec<PathBuf>,
150 requested_locale: Option<LanguageIdentifier>,
151 additional_ftl_path: Option<&Path>,
152 with_directionality_markers: bool,
153 ) -> Result<Option<Lrc<FluentBundle>>, TranslationBundleError> {
154 if requested_locale.is_none() && additional_ftl_path.is_none() {
158 let fallback_locale = langid!("en-US");
159 let requested_fallback_locale = requested_locale.as_ref() == Some(&fallback_locale);
161 // If there is only `-Z additional-ftl-path`, assume locale is "en-US", otherwise use user
163 let locale = requested_locale.clone().unwrap_or(fallback_locale);
165 let mut bundle = new_bundle(vec![locale]);
167 // Fluent diagnostics can insert directionality isolation markers around interpolated variables
168 // indicating that there may be a shift from right-to-left to left-to-right text (or
169 // vice-versa). These are disabled because they are sometimes visible in the error output, but
170 // may be worth investigating in future (for example: if type names are left-to-right and the
171 // surrounding diagnostic messages are right-to-left, then these might be helpful).
172 bundle.set_use_isolating(with_directionality_markers);
174 // If the user requests the default locale then don't try to load anything.
175 if !requested_fallback_locale && let Some(requested_locale) = requested_locale {
176 let mut found_resources = false;
177 for sysroot in user_provided_sysroot.iter_mut().chain(sysroot_candidates.iter_mut()) {
178 sysroot.push("share");
179 sysroot.push("locale");
180 sysroot.push(requested_locale.to_string());
183 if !sysroot.exists() {
188 if !sysroot.is_dir() {
189 return Err(TranslationBundleError::LocaleIsNotDir);
192 for entry in sysroot.read_dir().map_err(TranslationBundleError::ReadLocalesDir)? {
193 let entry = entry.map_err(TranslationBundleError::ReadLocalesDirEntry)?;
194 let path = entry.path();
196 if path.extension().and_then(|s| s.to_str()) != Some("ftl") {
202 fs::read_to_string(path).map_err(TranslationBundleError::ReadFtl)?;
204 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
206 bundle.add_resource(resource).map_err(TranslationBundleError::from)?;
207 found_resources = true;
211 if !found_resources {
212 return Err(TranslationBundleError::MissingLocale);
216 if let Some(additional_ftl_path) = additional_ftl_path {
218 fs::read_to_string(additional_ftl_path).map_err(TranslationBundleError::ReadFtl)?;
220 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
222 bundle.add_resource_overriding(resource);
225 let bundle = Lrc::new(bundle);
229 /// Type alias for the result of `fallback_fluent_bundle` - a reference-counted pointer to a lazily
230 /// evaluated fluent bundle.
231 pub type LazyFallbackBundle = Lrc<Lazy<FluentBundle, impl FnOnce() -> FluentBundle>>;
233 /// Return the default `FluentBundle` with standard "en-US" diagnostic messages.
234 #[instrument(level = "trace")]
235 pub fn fallback_fluent_bundle(
236 resources: &'static [&'static str],
237 with_directionality_markers: bool,
238 ) -> LazyFallbackBundle {
239 Lrc::new(Lazy::new(move || {
240 let mut fallback_bundle = new_bundle(vec![langid!("en-US")]);
241 // See comment in `fluent_bundle`.
242 fallback_bundle.set_use_isolating(with_directionality_markers);
244 for resource in resources {
245 let resource = FluentResource::try_new(resource.to_string())
246 .expect("failed to parse fallback fluent resource");
248 fallback_bundle.add_resource_overriding(resource);
255 /// Identifier for the Fluent message/attribute corresponding to a diagnostic message.
256 type FluentId = Cow<'static, str>;
258 /// Abstraction over a message in a subdiagnostic (i.e. label, note, help, etc) to support both
259 /// translatable and non-translatable diagnostic messages.
261 /// Translatable messages for subdiagnostics are typically attributes attached to a larger Fluent
262 /// message so messages of this type must be combined with a `DiagnosticMessage` (using
263 /// `DiagnosticMessage::with_subdiagnostic_message`) before rendering. However, subdiagnostics from
264 /// the `SessionSubdiagnostic` derive refer to Fluent identifiers directly.
265 #[rustc_diagnostic_item = "SubdiagnosticMessage"]
266 pub enum SubdiagnosticMessage {
267 /// Non-translatable diagnostic message.
268 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
270 /// Identifier of a Fluent message. Instances of this variant are generated by the
271 /// `SessionSubdiagnostic` derive.
272 FluentIdentifier(FluentId),
273 /// Attribute of a Fluent message. Needs to be combined with a Fluent identifier to produce an
274 /// actual translated message. Instances of this variant are generated by the `fluent_messages`
277 /// <https://projectfluent.org/fluent/guide/attributes.html>
278 FluentAttr(FluentId),
281 /// `From` impl that enables existing diagnostic calls to functions which now take
282 /// `impl Into<SubdiagnosticMessage>` to continue to work as before.
283 impl<S: Into<String>> From<S> for SubdiagnosticMessage {
284 fn from(s: S) -> Self {
285 SubdiagnosticMessage::Str(s.into())
289 /// Abstraction over a message in a diagnostic to support both translatable and non-translatable
290 /// diagnostic messages.
292 /// Intended to be removed once diagnostics are entirely translatable.
293 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
294 #[rustc_diagnostic_item = "DiagnosticMessage"]
295 pub enum DiagnosticMessage {
296 /// Non-translatable diagnostic message.
297 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
299 /// Identifier for a Fluent message (with optional attribute) corresponding to the diagnostic
302 /// <https://projectfluent.org/fluent/guide/hello.html>
303 /// <https://projectfluent.org/fluent/guide/attributes.html>
304 FluentIdentifier(FluentId, Option<FluentId>),
307 impl DiagnosticMessage {
308 /// Given a `SubdiagnosticMessage` which may contain a Fluent attribute, create a new
309 /// `DiagnosticMessage` that combines that attribute with the Fluent identifier of `self`.
311 /// - If the `SubdiagnosticMessage` is non-translatable then return the message as a
312 /// `DiagnosticMessage`.
313 /// - If `self` is non-translatable then return `self`'s message.
314 pub fn with_subdiagnostic_message(&self, sub: SubdiagnosticMessage) -> Self {
315 let attr = match sub {
316 SubdiagnosticMessage::Str(s) => return DiagnosticMessage::Str(s),
317 SubdiagnosticMessage::FluentIdentifier(id) => {
318 return DiagnosticMessage::FluentIdentifier(id, None);
320 SubdiagnosticMessage::FluentAttr(attr) => attr,
324 DiagnosticMessage::Str(s) => DiagnosticMessage::Str(s.clone()),
325 DiagnosticMessage::FluentIdentifier(id, _) => {
326 DiagnosticMessage::FluentIdentifier(id.clone(), Some(attr))
331 /// Returns the `String` contained within the `DiagnosticMessage::Str` variant, assuming that
332 /// this diagnostic message is of the legacy, non-translatable variety. Panics if this
333 /// assumption does not hold.
335 /// Don't use this - it exists to support some places that do comparison with diagnostic
337 pub fn expect_str(&self) -> &str {
339 DiagnosticMessage::Str(s) => s,
340 _ => panic!("expected non-translatable diagnostic message"),
345 /// `From` impl that enables existing diagnostic calls to functions which now take
346 /// `impl Into<DiagnosticMessage>` to continue to work as before.
347 impl<S: Into<String>> From<S> for DiagnosticMessage {
348 fn from(s: S) -> Self {
349 DiagnosticMessage::Str(s.into())
353 /// Translating *into* a subdiagnostic message from a diagnostic message is a little strange - but
354 /// the subdiagnostic functions (e.g. `span_label`) take a `SubdiagnosticMessage` and the
355 /// subdiagnostic derive refers to typed identifiers that are `DiagnosticMessage`s, so need to be
356 /// able to convert between these, as much as they'll be converted back into `DiagnosticMessage`
357 /// using `with_subdiagnostic_message` eventually. Don't use this other than for the derive.
358 impl Into<SubdiagnosticMessage> for DiagnosticMessage {
359 fn into(self) -> SubdiagnosticMessage {
361 DiagnosticMessage::Str(s) => SubdiagnosticMessage::Str(s),
362 DiagnosticMessage::FluentIdentifier(id, None) => {
363 SubdiagnosticMessage::FluentIdentifier(id)
365 // There isn't really a sensible behaviour for this because it loses information but
366 // this is the most sensible of the behaviours.
367 DiagnosticMessage::FluentIdentifier(_, Some(attr)) => {
368 SubdiagnosticMessage::FluentAttr(attr)
374 /// A span together with some additional data.
375 #[derive(Clone, Debug)]
376 pub struct SpanLabel {
377 /// The span we are going to include in the final snippet.
380 /// Is this a primary span? This is the "locus" of the message,
381 /// and is indicated with a `^^^^` underline, versus `----`.
382 pub is_primary: bool,
384 /// What label should we attach to this span (if any)?
385 pub label: Option<DiagnosticMessage>,
388 /// A collection of `Span`s.
390 /// Spans have two orthogonal attributes:
392 /// - They can be *primary spans*. In this case they are the locus of
393 /// the error, and would be rendered with `^^^`.
394 /// - They can have a *label*. In this case, the label is written next
395 /// to the mark in the snippet when we render.
396 #[derive(Clone, Debug, Hash, PartialEq, Eq, Encodable, Decodable)]
397 pub struct MultiSpan {
398 primary_spans: Vec<Span>,
399 span_labels: Vec<(Span, DiagnosticMessage)>,
404 pub fn new() -> MultiSpan {
405 MultiSpan { primary_spans: vec![], span_labels: vec![] }
408 pub fn from_span(primary_span: Span) -> MultiSpan {
409 MultiSpan { primary_spans: vec![primary_span], span_labels: vec![] }
412 pub fn from_spans(mut vec: Vec<Span>) -> MultiSpan {
414 MultiSpan { primary_spans: vec, span_labels: vec![] }
417 pub fn push_span_label(&mut self, span: Span, label: impl Into<DiagnosticMessage>) {
418 self.span_labels.push((span, label.into()));
421 /// Selects the first primary span (if any).
422 pub fn primary_span(&self) -> Option<Span> {
423 self.primary_spans.first().cloned()
426 /// Returns all primary spans.
427 pub fn primary_spans(&self) -> &[Span] {
431 /// Returns `true` if any of the primary spans are displayable.
432 pub fn has_primary_spans(&self) -> bool {
436 /// Returns `true` if this contains only a dummy primary span with any hygienic context.
437 pub fn is_dummy(&self) -> bool {
438 self.primary_spans.iter().all(|sp| sp.is_dummy())
441 /// Replaces all occurrences of one Span with another. Used to move `Span`s in areas that don't
442 /// display well (like std macros). Returns whether replacements occurred.
443 pub fn replace(&mut self, before: Span, after: Span) -> bool {
444 let mut replacements_occurred = false;
445 for primary_span in &mut self.primary_spans {
446 if *primary_span == before {
447 *primary_span = after;
448 replacements_occurred = true;
451 for span_label in &mut self.span_labels {
452 if span_label.0 == before {
453 span_label.0 = after;
454 replacements_occurred = true;
457 replacements_occurred
460 /// Returns the strings to highlight. We always ensure that there
461 /// is an entry for each of the primary spans -- for each primary
462 /// span `P`, if there is at least one label with span `P`, we return
463 /// those labels (marked as primary). But otherwise we return
464 /// `SpanLabel` instances with empty labels.
465 pub fn span_labels(&self) -> Vec<SpanLabel> {
466 let is_primary = |span| self.primary_spans.contains(&span);
468 let mut span_labels = self
471 .map(|&(span, ref label)| SpanLabel {
473 is_primary: is_primary(span),
474 label: Some(label.clone()),
476 .collect::<Vec<_>>();
478 for &span in &self.primary_spans {
479 if !span_labels.iter().any(|sl| sl.span == span) {
480 span_labels.push(SpanLabel { span, is_primary: true, label: None });
487 /// Returns `true` if any of the span labels is displayable.
488 pub fn has_span_labels(&self) -> bool {
489 self.span_labels.iter().any(|(sp, _)| !sp.is_dummy())
493 impl From<Span> for MultiSpan {
494 fn from(span: Span) -> MultiSpan {
495 MultiSpan::from_span(span)
499 impl From<Vec<Span>> for MultiSpan {
500 fn from(spans: Vec<Span>) -> MultiSpan {
501 MultiSpan::from_spans(spans)