1 #![feature(let_chains)]
3 #![feature(rustc_attrs)]
4 #![feature(type_alias_impl_trait)]
6 use fluent_bundle::FluentResource;
7 use fluent_syntax::parser::ParserError;
8 use rustc_data_structures::sync::Lrc;
9 use rustc_macros::{fluent_messages, Decodable, Encodable};
12 use std::error::Error;
16 use std::path::{Path, PathBuf};
17 use tracing::{instrument, trace};
19 #[cfg(not(parallel_compiler))]
20 use std::cell::LazyCell as Lazy;
21 #[cfg(parallel_compiler)]
22 use std::sync::LazyLock as Lazy;
24 #[cfg(parallel_compiler)]
25 use intl_memoizer::concurrent::IntlLangMemoizer;
26 #[cfg(not(parallel_compiler))]
27 use intl_memoizer::IntlLangMemoizer;
29 pub use fluent_bundle::{FluentArgs, FluentError, FluentValue};
30 pub use unic_langid::{langid, LanguageIdentifier};
32 // Generates `DEFAULT_LOCALE_RESOURCES` static and `fluent_generated` module.
34 parser => "../locales/en-US/parser.ftl",
35 privacy => "../locales/en-US/privacy.ftl",
36 typeck => "../locales/en-US/typeck.ftl",
37 builtin_macros => "../locales/en-US/builtin_macros.ftl",
38 borrowck => "../locales/en-US/borrowck.ftl",
41 pub use fluent_generated::{self as fluent, DEFAULT_LOCALE_RESOURCES};
43 pub type FluentBundle = fluent_bundle::bundle::FluentBundle<FluentResource, IntlLangMemoizer>;
45 #[cfg(parallel_compiler)]
46 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
47 FluentBundle::new_concurrent(locales)
50 #[cfg(not(parallel_compiler))]
51 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
52 FluentBundle::new(locales)
56 pub enum TranslationBundleError {
57 /// Failed to read from `.ftl` file.
59 /// Failed to parse contents of `.ftl` file.
60 ParseFtl(ParserError),
61 /// Failed to add `FluentResource` to `FluentBundle`.
62 AddResource(FluentError),
63 /// `$sysroot/share/locale/$locale` does not exist.
65 /// Cannot read directory entries of `$sysroot/share/locale/$locale`.
66 ReadLocalesDir(io::Error),
67 /// Cannot read directory entry of `$sysroot/share/locale/$locale`.
68 ReadLocalesDirEntry(io::Error),
69 /// `$sysroot/share/locale/$locale` is not a directory.
73 impl fmt::Display for TranslationBundleError {
74 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
76 TranslationBundleError::ReadFtl(e) => write!(f, "could not read ftl file: {}", e),
77 TranslationBundleError::ParseFtl(e) => {
78 write!(f, "could not parse ftl file: {}", e)
80 TranslationBundleError::AddResource(e) => write!(f, "failed to add resource: {}", e),
81 TranslationBundleError::MissingLocale => write!(f, "missing locale directory"),
82 TranslationBundleError::ReadLocalesDir(e) => {
83 write!(f, "could not read locales dir: {}", e)
85 TranslationBundleError::ReadLocalesDirEntry(e) => {
86 write!(f, "could not read locales dir entry: {}", e)
88 TranslationBundleError::LocaleIsNotDir => {
89 write!(f, "`$sysroot/share/locales/$locale` is not a directory")
95 impl Error for TranslationBundleError {
96 fn source(&self) -> Option<&(dyn Error + 'static)> {
98 TranslationBundleError::ReadFtl(e) => Some(e),
99 TranslationBundleError::ParseFtl(e) => Some(e),
100 TranslationBundleError::AddResource(e) => Some(e),
101 TranslationBundleError::MissingLocale => None,
102 TranslationBundleError::ReadLocalesDir(e) => Some(e),
103 TranslationBundleError::ReadLocalesDirEntry(e) => Some(e),
104 TranslationBundleError::LocaleIsNotDir => None,
109 impl From<(FluentResource, Vec<ParserError>)> for TranslationBundleError {
110 fn from((_, mut errs): (FluentResource, Vec<ParserError>)) -> Self {
111 TranslationBundleError::ParseFtl(errs.pop().expect("failed ftl parse with no errors"))
115 impl From<Vec<FluentError>> for TranslationBundleError {
116 fn from(mut errs: Vec<FluentError>) -> Self {
117 TranslationBundleError::AddResource(
118 errs.pop().expect("failed adding resource to bundle with no errors"),
123 /// Returns Fluent bundle with the user's locale resources from
124 /// `$sysroot/share/locale/$requested_locale/*.ftl`.
126 /// If `-Z additional-ftl-path` was provided, load that resource and add it to the bundle
127 /// (overriding any conflicting messages).
128 #[instrument(level = "trace")]
129 pub fn fluent_bundle(
130 mut user_provided_sysroot: Option<PathBuf>,
131 mut sysroot_candidates: Vec<PathBuf>,
132 requested_locale: Option<LanguageIdentifier>,
133 additional_ftl_path: Option<&Path>,
134 with_directionality_markers: bool,
135 ) -> Result<Option<Lrc<FluentBundle>>, TranslationBundleError> {
136 if requested_locale.is_none() && additional_ftl_path.is_none() {
140 let fallback_locale = langid!("en-US");
141 let requested_fallback_locale = requested_locale.as_ref() == Some(&fallback_locale);
143 // If there is only `-Z additional-ftl-path`, assume locale is "en-US", otherwise use user
145 let locale = requested_locale.clone().unwrap_or(fallback_locale);
147 let mut bundle = new_bundle(vec![locale]);
149 // Fluent diagnostics can insert directionality isolation markers around interpolated variables
150 // indicating that there may be a shift from right-to-left to left-to-right text (or
151 // vice-versa). These are disabled because they are sometimes visible in the error output, but
152 // may be worth investigating in future (for example: if type names are left-to-right and the
153 // surrounding diagnostic messages are right-to-left, then these might be helpful).
154 bundle.set_use_isolating(with_directionality_markers);
156 // If the user requests the default locale then don't try to load anything.
157 if !requested_fallback_locale && let Some(requested_locale) = requested_locale {
158 let mut found_resources = false;
159 for sysroot in user_provided_sysroot.iter_mut().chain(sysroot_candidates.iter_mut()) {
160 sysroot.push("share");
161 sysroot.push("locale");
162 sysroot.push(requested_locale.to_string());
165 if !sysroot.exists() {
170 if !sysroot.is_dir() {
171 return Err(TranslationBundleError::LocaleIsNotDir);
174 for entry in sysroot.read_dir().map_err(TranslationBundleError::ReadLocalesDir)? {
175 let entry = entry.map_err(TranslationBundleError::ReadLocalesDirEntry)?;
176 let path = entry.path();
178 if path.extension().and_then(|s| s.to_str()) != Some("ftl") {
184 fs::read_to_string(path).map_err(TranslationBundleError::ReadFtl)?;
186 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
188 bundle.add_resource(resource).map_err(TranslationBundleError::from)?;
189 found_resources = true;
193 if !found_resources {
194 return Err(TranslationBundleError::MissingLocale);
198 if let Some(additional_ftl_path) = additional_ftl_path {
200 fs::read_to_string(additional_ftl_path).map_err(TranslationBundleError::ReadFtl)?;
202 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
204 bundle.add_resource_overriding(resource);
207 let bundle = Lrc::new(bundle);
211 /// Type alias for the result of `fallback_fluent_bundle` - a reference-counted pointer to a lazily
212 /// evaluated fluent bundle.
213 pub type LazyFallbackBundle = Lrc<Lazy<FluentBundle, impl FnOnce() -> FluentBundle>>;
215 /// Return the default `FluentBundle` with standard "en-US" diagnostic messages.
216 #[instrument(level = "trace")]
217 pub fn fallback_fluent_bundle(
218 resources: &'static [&'static str],
219 with_directionality_markers: bool,
220 ) -> LazyFallbackBundle {
221 Lrc::new(Lazy::new(move || {
222 let mut fallback_bundle = new_bundle(vec![langid!("en-US")]);
223 // See comment in `fluent_bundle`.
224 fallback_bundle.set_use_isolating(with_directionality_markers);
226 for resource in resources {
227 let resource = FluentResource::try_new(resource.to_string())
228 .expect("failed to parse fallback fluent resource");
230 fallback_bundle.add_resource_overriding(resource);
237 /// Identifier for the Fluent message/attribute corresponding to a diagnostic message.
238 type FluentId = Cow<'static, str>;
240 /// Abstraction over a message in a subdiagnostic (i.e. label, note, help, etc) to support both
241 /// translatable and non-translatable diagnostic messages.
243 /// Translatable messages for subdiagnostics are typically attributes attached to a larger Fluent
244 /// message so messages of this type must be combined with a `DiagnosticMessage` (using
245 /// `DiagnosticMessage::with_subdiagnostic_message`) before rendering. However, subdiagnostics from
246 /// the `SessionSubdiagnostic` derive refer to Fluent identifiers directly.
247 #[rustc_diagnostic_item = "SubdiagnosticMessage"]
248 pub enum SubdiagnosticMessage {
249 /// Non-translatable diagnostic message.
250 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
252 /// Identifier of a Fluent message. Instances of this variant are generated by the
253 /// `SessionSubdiagnostic` derive.
254 FluentIdentifier(FluentId),
255 /// Attribute of a Fluent message. Needs to be combined with a Fluent identifier to produce an
256 /// actual translated message. Instances of this variant are generated by the `fluent_messages`
259 /// <https://projectfluent.org/fluent/guide/attributes.html>
260 FluentAttr(FluentId),
263 /// `From` impl that enables existing diagnostic calls to functions which now take
264 /// `impl Into<SubdiagnosticMessage>` to continue to work as before.
265 impl<S: Into<String>> From<S> for SubdiagnosticMessage {
266 fn from(s: S) -> Self {
267 SubdiagnosticMessage::Str(s.into())
271 /// Abstraction over a message in a diagnostic to support both translatable and non-translatable
272 /// diagnostic messages.
274 /// Intended to be removed once diagnostics are entirely translatable.
275 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
276 #[rustc_diagnostic_item = "DiagnosticMessage"]
277 pub enum DiagnosticMessage {
278 /// Non-translatable diagnostic message.
279 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
281 /// Identifier for a Fluent message (with optional attribute) corresponding to the diagnostic
284 /// <https://projectfluent.org/fluent/guide/hello.html>
285 /// <https://projectfluent.org/fluent/guide/attributes.html>
286 FluentIdentifier(FluentId, Option<FluentId>),
289 impl DiagnosticMessage {
290 /// Given a `SubdiagnosticMessage` which may contain a Fluent attribute, create a new
291 /// `DiagnosticMessage` that combines that attribute with the Fluent identifier of `self`.
293 /// - If the `SubdiagnosticMessage` is non-translatable then return the message as a
294 /// `DiagnosticMessage`.
295 /// - If `self` is non-translatable then return `self`'s message.
296 pub fn with_subdiagnostic_message(&self, sub: SubdiagnosticMessage) -> Self {
297 let attr = match sub {
298 SubdiagnosticMessage::Str(s) => return DiagnosticMessage::Str(s.clone()),
299 SubdiagnosticMessage::FluentIdentifier(id) => {
300 return DiagnosticMessage::FluentIdentifier(id, None);
302 SubdiagnosticMessage::FluentAttr(attr) => attr,
306 DiagnosticMessage::Str(s) => DiagnosticMessage::Str(s.clone()),
307 DiagnosticMessage::FluentIdentifier(id, _) => {
308 DiagnosticMessage::FluentIdentifier(id.clone(), Some(attr))
313 /// Returns the `String` contained within the `DiagnosticMessage::Str` variant, assuming that
314 /// this diagnostic message is of the legacy, non-translatable variety. Panics if this
315 /// assumption does not hold.
317 /// Don't use this - it exists to support some places that do comparison with diagnostic
319 pub fn expect_str(&self) -> &str {
321 DiagnosticMessage::Str(s) => s,
322 _ => panic!("expected non-translatable diagnostic message"),
327 /// `From` impl that enables existing diagnostic calls to functions which now take
328 /// `impl Into<DiagnosticMessage>` to continue to work as before.
329 impl<S: Into<String>> From<S> for DiagnosticMessage {
330 fn from(s: S) -> Self {
331 DiagnosticMessage::Str(s.into())
335 /// Translating *into* a subdiagnostic message from a diagnostic message is a little strange - but
336 /// the subdiagnostic functions (e.g. `span_label`) take a `SubdiagnosticMessage` and the
337 /// subdiagnostic derive refers to typed identifiers that are `DiagnosticMessage`s, so need to be
338 /// able to convert between these, as much as they'll be converted back into `DiagnosticMessage`
339 /// using `with_subdiagnostic_message` eventually. Don't use this other than for the derive.
340 impl Into<SubdiagnosticMessage> for DiagnosticMessage {
341 fn into(self) -> SubdiagnosticMessage {
343 DiagnosticMessage::Str(s) => SubdiagnosticMessage::Str(s),
344 DiagnosticMessage::FluentIdentifier(id, None) => {
345 SubdiagnosticMessage::FluentIdentifier(id)
347 // There isn't really a sensible behaviour for this because it loses information but
348 // this is the most sensible of the behaviours.
349 DiagnosticMessage::FluentIdentifier(_, Some(attr)) => {
350 SubdiagnosticMessage::FluentAttr(attr)
356 /// A span together with some additional data.
357 #[derive(Clone, Debug)]
358 pub struct SpanLabel {
359 /// The span we are going to include in the final snippet.
362 /// Is this a primary span? This is the "locus" of the message,
363 /// and is indicated with a `^^^^` underline, versus `----`.
364 pub is_primary: bool,
366 /// What label should we attach to this span (if any)?
367 pub label: Option<DiagnosticMessage>,
370 /// A collection of `Span`s.
372 /// Spans have two orthogonal attributes:
374 /// - They can be *primary spans*. In this case they are the locus of
375 /// the error, and would be rendered with `^^^`.
376 /// - They can have a *label*. In this case, the label is written next
377 /// to the mark in the snippet when we render.
378 #[derive(Clone, Debug, Hash, PartialEq, Eq, Encodable, Decodable)]
379 pub struct MultiSpan {
380 primary_spans: Vec<Span>,
381 span_labels: Vec<(Span, DiagnosticMessage)>,
386 pub fn new() -> MultiSpan {
387 MultiSpan { primary_spans: vec![], span_labels: vec![] }
390 pub fn from_span(primary_span: Span) -> MultiSpan {
391 MultiSpan { primary_spans: vec![primary_span], span_labels: vec![] }
394 pub fn from_spans(mut vec: Vec<Span>) -> MultiSpan {
396 MultiSpan { primary_spans: vec, span_labels: vec![] }
399 pub fn push_span_label(&mut self, span: Span, label: impl Into<DiagnosticMessage>) {
400 self.span_labels.push((span, label.into()));
403 /// Selects the first primary span (if any).
404 pub fn primary_span(&self) -> Option<Span> {
405 self.primary_spans.first().cloned()
408 /// Returns all primary spans.
409 pub fn primary_spans(&self) -> &[Span] {
413 /// Returns `true` if any of the primary spans are displayable.
414 pub fn has_primary_spans(&self) -> bool {
418 /// Returns `true` if this contains only a dummy primary span with any hygienic context.
419 pub fn is_dummy(&self) -> bool {
420 self.primary_spans.iter().all(|sp| sp.is_dummy())
423 /// Replaces all occurrences of one Span with another. Used to move `Span`s in areas that don't
424 /// display well (like std macros). Returns whether replacements occurred.
425 pub fn replace(&mut self, before: Span, after: Span) -> bool {
426 let mut replacements_occurred = false;
427 for primary_span in &mut self.primary_spans {
428 if *primary_span == before {
429 *primary_span = after;
430 replacements_occurred = true;
433 for span_label in &mut self.span_labels {
434 if span_label.0 == before {
435 span_label.0 = after;
436 replacements_occurred = true;
439 replacements_occurred
442 /// Returns the strings to highlight. We always ensure that there
443 /// is an entry for each of the primary spans -- for each primary
444 /// span `P`, if there is at least one label with span `P`, we return
445 /// those labels (marked as primary). But otherwise we return
446 /// `SpanLabel` instances with empty labels.
447 pub fn span_labels(&self) -> Vec<SpanLabel> {
448 let is_primary = |span| self.primary_spans.contains(&span);
450 let mut span_labels = self
453 .map(|&(span, ref label)| SpanLabel {
455 is_primary: is_primary(span),
456 label: Some(label.clone()),
458 .collect::<Vec<_>>();
460 for &span in &self.primary_spans {
461 if !span_labels.iter().any(|sl| sl.span == span) {
462 span_labels.push(SpanLabel { span, is_primary: true, label: None });
469 /// Returns `true` if any of the span labels is displayable.
470 pub fn has_span_labels(&self) -> bool {
471 self.span_labels.iter().any(|(sp, _)| !sp.is_dummy())
475 impl From<Span> for MultiSpan {
476 fn from(span: Span) -> MultiSpan {
477 MultiSpan::from_span(span)
481 impl From<Vec<Span>> for MultiSpan {
482 fn from(spans: Vec<Span>) -> MultiSpan {
483 MultiSpan::from_spans(spans)