1 files changed, 59 insertions, 0 deletions
diff --git a/third_party/rust/fluent-bundle/src/concurrent.rs b/third_party/rust/fluent-bundle/src/concurrent.rs
new file mode 100644
index 0000000000..b87225efee
--- /dev/null
+++ b/third_party/rust/fluent-bundle/src/concurrent.rs
@@ -0,0 +1,59 @@
+use intl_memoizer::{concurrent::IntlLangMemoizer, Memoizable};
+use rustc_hash::FxHashMap;
+use unic_langid::LanguageIdentifier;
+
+use crate::bundle::FluentBundle;
+use crate::memoizer::MemoizerKind;
+use crate::types::FluentType;
+
+impl<R> FluentBundle<R, IntlLangMemoizer> {
+    /// A constructor analogous to [`FluentBundle::new`] but operating
+    /// on a concurrent version of [`IntlLangMemoizer`] over [`Mutex`](std::sync::Mutex).
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use fluent_bundle::bundle::FluentBundle;
+    /// use fluent_bundle::FluentResource;
+    /// use unic_langid::langid;
+    ///
+    /// let langid_en = langid!("en-US");
+    /// let mut bundle: FluentBundle<FluentResource, _> =
+    ///     FluentBundle::new_concurrent(vec![langid_en]);
+    /// ```
+    pub fn new_concurrent(locales: Vec<LanguageIdentifier>) -> Self {
+        let first_locale = locales.get(0).cloned().unwrap_or_default();
+        Self {
+            locales,
+            resources: vec![],
+            entries: FxHashMap::default(),
+            intls: IntlLangMemoizer::new(first_locale),
+            use_isolating: true,
+            transform: None,
+            formatter: None,
+        }
+    }
+}
+
+impl MemoizerKind for IntlLangMemoizer {
+    fn new(lang: LanguageIdentifier) -> Self
+    where
+        Self: Sized,
+    {
+        Self::new(lang)
+    }
+
+    fn with_try_get_threadsafe<I, R, U>(&self, args: I::Args, cb: U) -> Result<R, I::Error>
+    where
+        Self: Sized,
+        I: Memoizable + Send + Sync + 'static,
+        I::Args: Send + Sync + 'static,
+        U: FnOnce(&I) -> R,
+    {
+        self.with_try_get(args, cb)
+    }
+
+    fn stringify_value(&self, value: &dyn FluentType) -> std::borrow::Cow<'static, str> {
+        value.as_string_threadsafe(self)
+    }
+}