1 files changed, 111 insertions, 0 deletions
diff --git a/vendor/icu_provider_adapters/src/either.rs b/vendor/icu_provider_adapters/src/either.rs
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index 000000000..b62a9c3fb
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+++ b/vendor/icu_provider_adapters/src/either.rs
@@ -0,0 +1,111 @@
+// This file is part of ICU4X. For terms of use, please see the file
+// called LICENSE at the top level of the ICU4X source tree
+// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
+
+//! Helpers for switching between multiple providers.
+
+use icu_provider::prelude::*;
+
+#[cfg(feature = "datagen")]
+use icu_provider::datagen;
+
+/// A provider that is one of two types determined at runtime.
+///
+/// Data provider traits implemented by both `P0` and `P1` are implemented on
+/// `EitherProvider<P0, P1>`.
+#[allow(clippy::exhaustive_enums)] // this is stable
+pub enum EitherProvider<P0, P1> {
+    /// A value of type `P0`.
+    A(P0),
+    /// A value of type `P1`.
+    B(P1),
+}
+
+impl<P0: AnyProvider, P1: AnyProvider> AnyProvider for EitherProvider<P0, P1> {
+    #[inline]
+    fn load_any(&self, key: DataKey, req: DataRequest) -> Result<AnyResponse, DataError> {
+        use EitherProvider::*;
+        match self {
+            A(p) => p.load_any(key, req),
+            B(p) => p.load_any(key, req),
+        }
+    }
+}
+
+impl<P0: BufferProvider, P1: BufferProvider> BufferProvider for EitherProvider<P0, P1> {
+    #[inline]
+    fn load_buffer(
+        &self,
+        key: DataKey,
+        req: DataRequest,
+    ) -> Result<DataResponse<BufferMarker>, DataError> {
+        use EitherProvider::*;
+        match self {
+            A(p) => p.load_buffer(key, req),
+            B(p) => p.load_buffer(key, req),
+        }
+    }
+}
+
+impl<M: DataMarker, P0: DynamicDataProvider<M>, P1: DynamicDataProvider<M>> DynamicDataProvider<M>
+    for EitherProvider<P0, P1>
+{
+    #[inline]
+    fn load_data(&self, key: DataKey, req: DataRequest) -> Result<DataResponse<M>, DataError> {
+        use EitherProvider::*;
+        match self {
+            A(p) => p.load_data(key, req),
+            B(p) => p.load_data(key, req),
+        }
+    }
+}
+
+impl<M: KeyedDataMarker, P0: DataProvider<M>, P1: DataProvider<M>> DataProvider<M>
+    for EitherProvider<P0, P1>
+{
+    #[inline]
+    fn load(&self, req: DataRequest) -> Result<DataResponse<M>, DataError> {
+        use EitherProvider::*;
+        match self {
+            A(p) => p.load(req),
+            B(p) => p.load(req),
+        }
+    }
+}
+
+#[cfg(feature = "datagen")]
+impl<
+        M: DataMarker,
+        P0: datagen::IterableDynamicDataProvider<M>,
+        P1: datagen::IterableDynamicDataProvider<M>,
+    > datagen::IterableDynamicDataProvider<M> for EitherProvider<P0, P1>
+{
+    #[inline]
+    fn supported_locales_for_key(
+        &self,
+        key: DataKey,
+    ) -> Result<alloc::vec::Vec<DataLocale>, DataError> {
+        use EitherProvider::*;
+        match self {
+            A(p) => p.supported_locales_for_key(key),
+            B(p) => p.supported_locales_for_key(key),
+        }
+    }
+}
+
+#[cfg(feature = "datagen")]
+impl<
+        M: KeyedDataMarker,
+        P0: datagen::IterableDataProvider<M>,
+        P1: datagen::IterableDataProvider<M>,
+    > datagen::IterableDataProvider<M> for EitherProvider<P0, P1>
+{
+    #[inline]
+    fn supported_locales(&self) -> Result<alloc::vec::Vec<DataLocale>, DataError> {
+        use EitherProvider::*;
+        match self {
+            A(p) => p.supported_locales(),
+            B(p) => p.supported_locales(),
+        }
+    }
+}