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 borrowck => "../locales/en-US/borrowck.ftl",
35 builtin_macros => "../locales/en-US/builtin_macros.ftl",
36 lint => "../locales/en-US/lint.ftl",
37 parser => "../locales/en-US/parser.ftl",
38 privacy => "../locales/en-US/privacy.ftl",
39 typeck => "../locales/en-US/typeck.ftl",
40 const_eval => "../locales/en-US/const_eval.ftl",
43 pub use fluent_generated::{self as fluent, DEFAULT_LOCALE_RESOURCES};
45 pub type FluentBundle = fluent_bundle::bundle::FluentBundle<FluentResource, IntlLangMemoizer>;
47 #[cfg(parallel_compiler)]
48 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
49 FluentBundle::new_concurrent(locales)
52 #[cfg(not(parallel_compiler))]
53 fn new_bundle(locales: Vec<LanguageIdentifier>) -> FluentBundle {
54 FluentBundle::new(locales)
58 pub enum TranslationBundleError {
59 /// Failed to read from `.ftl` file.
61 /// Failed to parse contents of `.ftl` file.
62 ParseFtl(ParserError),
63 /// Failed to add `FluentResource` to `FluentBundle`.
64 AddResource(FluentError),
65 /// `$sysroot/share/locale/$locale` does not exist.
67 /// Cannot read directory entries of `$sysroot/share/locale/$locale`.
68 ReadLocalesDir(io::Error),
69 /// Cannot read directory entry of `$sysroot/share/locale/$locale`.
70 ReadLocalesDirEntry(io::Error),
71 /// `$sysroot/share/locale/$locale` is not a directory.
75 impl fmt::Display for TranslationBundleError {
76 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
78 TranslationBundleError::ReadFtl(e) => write!(f, "could not read ftl file: {}", e),
79 TranslationBundleError::ParseFtl(e) => {
80 write!(f, "could not parse ftl file: {}", e)
82 TranslationBundleError::AddResource(e) => write!(f, "failed to add resource: {}", e),
83 TranslationBundleError::MissingLocale => write!(f, "missing locale directory"),
84 TranslationBundleError::ReadLocalesDir(e) => {
85 write!(f, "could not read locales dir: {}", e)
87 TranslationBundleError::ReadLocalesDirEntry(e) => {
88 write!(f, "could not read locales dir entry: {}", e)
90 TranslationBundleError::LocaleIsNotDir => {
91 write!(f, "`$sysroot/share/locales/$locale` is not a directory")
97 impl Error for TranslationBundleError {
98 fn source(&self) -> Option<&(dyn Error + 'static)> {
100 TranslationBundleError::ReadFtl(e) => Some(e),
101 TranslationBundleError::ParseFtl(e) => Some(e),
102 TranslationBundleError::AddResource(e) => Some(e),
103 TranslationBundleError::MissingLocale => None,
104 TranslationBundleError::ReadLocalesDir(e) => Some(e),
105 TranslationBundleError::ReadLocalesDirEntry(e) => Some(e),
106 TranslationBundleError::LocaleIsNotDir => None,
111 impl From<(FluentResource, Vec<ParserError>)> for TranslationBundleError {
112 fn from((_, mut errs): (FluentResource, Vec<ParserError>)) -> Self {
113 TranslationBundleError::ParseFtl(errs.pop().expect("failed ftl parse with no errors"))
117 impl From<Vec<FluentError>> for TranslationBundleError {
118 fn from(mut errs: Vec<FluentError>) -> Self {
119 TranslationBundleError::AddResource(
120 errs.pop().expect("failed adding resource to bundle with no errors"),
125 /// Returns Fluent bundle with the user's locale resources from
126 /// `$sysroot/share/locale/$requested_locale/*.ftl`.
128 /// If `-Z additional-ftl-path` was provided, load that resource and add it to the bundle
129 /// (overriding any conflicting messages).
130 #[instrument(level = "trace")]
131 pub fn fluent_bundle(
132 mut user_provided_sysroot: Option<PathBuf>,
133 mut sysroot_candidates: Vec<PathBuf>,
134 requested_locale: Option<LanguageIdentifier>,
135 additional_ftl_path: Option<&Path>,
136 with_directionality_markers: bool,
137 ) -> Result<Option<Lrc<FluentBundle>>, TranslationBundleError> {
138 if requested_locale.is_none() && additional_ftl_path.is_none() {
142 let fallback_locale = langid!("en-US");
143 let requested_fallback_locale = requested_locale.as_ref() == Some(&fallback_locale);
145 // If there is only `-Z additional-ftl-path`, assume locale is "en-US", otherwise use user
147 let locale = requested_locale.clone().unwrap_or(fallback_locale);
149 let mut bundle = new_bundle(vec![locale]);
151 // Fluent diagnostics can insert directionality isolation markers around interpolated variables
152 // indicating that there may be a shift from right-to-left to left-to-right text (or
153 // vice-versa). These are disabled because they are sometimes visible in the error output, but
154 // may be worth investigating in future (for example: if type names are left-to-right and the
155 // surrounding diagnostic messages are right-to-left, then these might be helpful).
156 bundle.set_use_isolating(with_directionality_markers);
158 // If the user requests the default locale then don't try to load anything.
159 if !requested_fallback_locale && let Some(requested_locale) = requested_locale {
160 let mut found_resources = false;
161 for sysroot in user_provided_sysroot.iter_mut().chain(sysroot_candidates.iter_mut()) {
162 sysroot.push("share");
163 sysroot.push("locale");
164 sysroot.push(requested_locale.to_string());
167 if !sysroot.exists() {
172 if !sysroot.is_dir() {
173 return Err(TranslationBundleError::LocaleIsNotDir);
176 for entry in sysroot.read_dir().map_err(TranslationBundleError::ReadLocalesDir)? {
177 let entry = entry.map_err(TranslationBundleError::ReadLocalesDirEntry)?;
178 let path = entry.path();
180 if path.extension().and_then(|s| s.to_str()) != Some("ftl") {
186 fs::read_to_string(path).map_err(TranslationBundleError::ReadFtl)?;
188 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
190 bundle.add_resource(resource).map_err(TranslationBundleError::from)?;
191 found_resources = true;
195 if !found_resources {
196 return Err(TranslationBundleError::MissingLocale);
200 if let Some(additional_ftl_path) = additional_ftl_path {
202 fs::read_to_string(additional_ftl_path).map_err(TranslationBundleError::ReadFtl)?;
204 FluentResource::try_new(resource_str).map_err(TranslationBundleError::from)?;
206 bundle.add_resource_overriding(resource);
209 let bundle = Lrc::new(bundle);
213 /// Type alias for the result of `fallback_fluent_bundle` - a reference-counted pointer to a lazily
214 /// evaluated fluent bundle.
215 pub type LazyFallbackBundle = Lrc<Lazy<FluentBundle, impl FnOnce() -> FluentBundle>>;
217 /// Return the default `FluentBundle` with standard "en-US" diagnostic messages.
218 #[instrument(level = "trace")]
219 pub fn fallback_fluent_bundle(
220 resources: &'static [&'static str],
221 with_directionality_markers: bool,
222 ) -> LazyFallbackBundle {
223 Lrc::new(Lazy::new(move || {
224 let mut fallback_bundle = new_bundle(vec![langid!("en-US")]);
225 // See comment in `fluent_bundle`.
226 fallback_bundle.set_use_isolating(with_directionality_markers);
228 for resource in resources {
229 let resource = FluentResource::try_new(resource.to_string())
230 .expect("failed to parse fallback fluent resource");
232 fallback_bundle.add_resource_overriding(resource);
239 /// Identifier for the Fluent message/attribute corresponding to a diagnostic message.
240 type FluentId = Cow<'static, str>;
242 /// Abstraction over a message in a subdiagnostic (i.e. label, note, help, etc) to support both
243 /// translatable and non-translatable diagnostic messages.
245 /// Translatable messages for subdiagnostics are typically attributes attached to a larger Fluent
246 /// message so messages of this type must be combined with a `DiagnosticMessage` (using
247 /// `DiagnosticMessage::with_subdiagnostic_message`) before rendering. However, subdiagnostics from
248 /// the `SessionSubdiagnostic` derive refer to Fluent identifiers directly.
249 #[rustc_diagnostic_item = "SubdiagnosticMessage"]
250 pub enum SubdiagnosticMessage {
251 /// Non-translatable diagnostic message.
252 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
254 /// Identifier of a Fluent message. Instances of this variant are generated by the
255 /// `SessionSubdiagnostic` derive.
256 FluentIdentifier(FluentId),
257 /// Attribute of a Fluent message. Needs to be combined with a Fluent identifier to produce an
258 /// actual translated message. Instances of this variant are generated by the `fluent_messages`
261 /// <https://projectfluent.org/fluent/guide/attributes.html>
262 FluentAttr(FluentId),
265 /// `From` impl that enables existing diagnostic calls to functions which now take
266 /// `impl Into<SubdiagnosticMessage>` to continue to work as before.
267 impl<S: Into<String>> From<S> for SubdiagnosticMessage {
268 fn from(s: S) -> Self {
269 SubdiagnosticMessage::Str(s.into())
273 /// Abstraction over a message in a diagnostic to support both translatable and non-translatable
274 /// diagnostic messages.
276 /// Intended to be removed once diagnostics are entirely translatable.
277 #[derive(Clone, Debug, PartialEq, Eq, Hash, Encodable, Decodable)]
278 #[rustc_diagnostic_item = "DiagnosticMessage"]
279 pub enum DiagnosticMessage {
280 /// Non-translatable diagnostic message.
281 // FIXME(davidtwco): can a `Cow<'static, str>` be used here?
283 /// Identifier for a Fluent message (with optional attribute) corresponding to the diagnostic
286 /// <https://projectfluent.org/fluent/guide/hello.html>
287 /// <https://projectfluent.org/fluent/guide/attributes.html>
288 FluentIdentifier(FluentId, Option<FluentId>),
291 impl DiagnosticMessage {
292 /// Given a `SubdiagnosticMessage` which may contain a Fluent attribute, create a new
293 /// `DiagnosticMessage` that combines that attribute with the Fluent identifier of `self`.
295 /// - If the `SubdiagnosticMessage` is non-translatable then return the message as a
296 /// `DiagnosticMessage`.
297 /// - If `self` is non-translatable then return `self`'s message.
298 pub fn with_subdiagnostic_message(&self, sub: SubdiagnosticMessage) -> Self {
299 let attr = match sub {
300 SubdiagnosticMessage::Str(s) => return DiagnosticMessage::Str(s.clone()),
301 SubdiagnosticMessage::FluentIdentifier(id) => {
302 return DiagnosticMessage::FluentIdentifier(id, None);
304 SubdiagnosticMessage::FluentAttr(attr) => attr,
308 DiagnosticMessage::Str(s) => DiagnosticMessage::Str(s.clone()),
309 DiagnosticMessage::FluentIdentifier(id, _) => {
310 DiagnosticMessage::FluentIdentifier(id.clone(), Some(attr))
315 /// Returns the `String` contained within the `DiagnosticMessage::Str` variant, assuming that
316 /// this diagnostic message is of the legacy, non-translatable variety. Panics if this
317 /// assumption does not hold.
319 /// Don't use this - it exists to support some places that do comparison with diagnostic
321 pub fn expect_str(&self) -> &str {
323 DiagnosticMessage::Str(s) => s,
324 _ => panic!("expected non-translatable diagnostic message"),
329 /// `From` impl that enables existing diagnostic calls to functions which now take
330 /// `impl Into<DiagnosticMessage>` to continue to work as before.
331 impl<S: Into<String>> From<S> for DiagnosticMessage {
332 fn from(s: S) -> Self {
333 DiagnosticMessage::Str(s.into())
337 /// Translating *into* a subdiagnostic message from a diagnostic message is a little strange - but
338 /// the subdiagnostic functions (e.g. `span_label`) take a `SubdiagnosticMessage` and the
339 /// subdiagnostic derive refers to typed identifiers that are `DiagnosticMessage`s, so need to be
340 /// able to convert between these, as much as they'll be converted back into `DiagnosticMessage`
341 /// using `with_subdiagnostic_message` eventually. Don't use this other than for the derive.
342 impl Into<SubdiagnosticMessage> for DiagnosticMessage {
343 fn into(self) -> SubdiagnosticMessage {
345 DiagnosticMessage::Str(s) => SubdiagnosticMessage::Str(s),
346 DiagnosticMessage::FluentIdentifier(id, None) => {
347 SubdiagnosticMessage::FluentIdentifier(id)
349 // There isn't really a sensible behaviour for this because it loses information but
350 // this is the most sensible of the behaviours.
351 DiagnosticMessage::FluentIdentifier(_, Some(attr)) => {
352 SubdiagnosticMessage::FluentAttr(attr)
358 /// A span together with some additional data.
359 #[derive(Clone, Debug)]
360 pub struct SpanLabel {
361 /// The span we are going to include in the final snippet.
364 /// Is this a primary span? This is the "locus" of the message,
365 /// and is indicated with a `^^^^` underline, versus `----`.
366 pub is_primary: bool,
368 /// What label should we attach to this span (if any)?
369 pub label: Option<DiagnosticMessage>,
372 /// A collection of `Span`s.
374 /// Spans have two orthogonal attributes:
376 /// - They can be *primary spans*. In this case they are the locus of
377 /// the error, and would be rendered with `^^^`.
378 /// - They can have a *label*. In this case, the label is written next
379 /// to the mark in the snippet when we render.
380 #[derive(Clone, Debug, Hash, PartialEq, Eq, Encodable, Decodable)]
381 pub struct MultiSpan {
382 primary_spans: Vec<Span>,
383 span_labels: Vec<(Span, DiagnosticMessage)>,
388 pub fn new() -> MultiSpan {
389 MultiSpan { primary_spans: vec![], span_labels: vec![] }
392 pub fn from_span(primary_span: Span) -> MultiSpan {
393 MultiSpan { primary_spans: vec![primary_span], span_labels: vec![] }
396 pub fn from_spans(mut vec: Vec<Span>) -> MultiSpan {
398 MultiSpan { primary_spans: vec, span_labels: vec![] }
401 pub fn push_span_label(&mut self, span: Span, label: impl Into<DiagnosticMessage>) {
402 self.span_labels.push((span, label.into()));
405 /// Selects the first primary span (if any).
406 pub fn primary_span(&self) -> Option<Span> {
407 self.primary_spans.first().cloned()
410 /// Returns all primary spans.
411 pub fn primary_spans(&self) -> &[Span] {
415 /// Returns `true` if any of the primary spans are displayable.
416 pub fn has_primary_spans(&self) -> bool {
420 /// Returns `true` if this contains only a dummy primary span with any hygienic context.
421 pub fn is_dummy(&self) -> bool {
422 self.primary_spans.iter().all(|sp| sp.is_dummy())
425 /// Replaces all occurrences of one Span with another. Used to move `Span`s in areas that don't
426 /// display well (like std macros). Returns whether replacements occurred.
427 pub fn replace(&mut self, before: Span, after: Span) -> bool {
428 let mut replacements_occurred = false;
429 for primary_span in &mut self.primary_spans {
430 if *primary_span == before {
431 *primary_span = after;
432 replacements_occurred = true;
435 for span_label in &mut self.span_labels {
436 if span_label.0 == before {
437 span_label.0 = after;
438 replacements_occurred = true;
441 replacements_occurred
444 /// Returns the strings to highlight. We always ensure that there
445 /// is an entry for each of the primary spans -- for each primary
446 /// span `P`, if there is at least one label with span `P`, we return
447 /// those labels (marked as primary). But otherwise we return
448 /// `SpanLabel` instances with empty labels.
449 pub fn span_labels(&self) -> Vec<SpanLabel> {
450 let is_primary = |span| self.primary_spans.contains(&span);
452 let mut span_labels = self
455 .map(|&(span, ref label)| SpanLabel {
457 is_primary: is_primary(span),
458 label: Some(label.clone()),
460 .collect::<Vec<_>>();
462 for &span in &self.primary_spans {
463 if !span_labels.iter().any(|sl| sl.span == span) {
464 span_labels.push(SpanLabel { span, is_primary: true, label: None });
471 /// Returns `true` if any of the span labels is displayable.
472 pub fn has_span_labels(&self) -> bool {
473 self.span_labels.iter().any(|(sp, _)| !sp.is_dummy())
477 impl From<Span> for MultiSpan {
478 fn from(span: Span) -> MultiSpan {
479 MultiSpan::from_span(span)
483 impl From<Vec<Span>> for MultiSpan {
484 fn from(spans: Vec<Span>) -> MultiSpan {
485 MultiSpan::from_spans(spans)