Merging upstream version 1.67.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/vendor/icu_provider_adapters/src/fork/macros.rs b/vendor/icu_provider_adapters/src/fork/macros.rs
new file mode 100644
index 000000000..7c18a9ba3
--- /dev/null
+++ b/vendor/icu_provider_adapters/src/fork/macros.rs
@@ -0,0 +1,71 @@
+// 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 ).
+
+/// Make a forking data provider with an arbitrary number of inner providers
+/// that are known at build time.
+///
+/// # Examples
+///
+/// ```
+/// use icu_provider_adapters::fork::ForkByKeyProvider;
+///
+/// // Some empty example providers:
+/// #[derive(Default, PartialEq, Debug)]
+/// struct Provider1;
+/// #[derive(Default, PartialEq, Debug)]
+/// struct Provider2;
+/// #[derive(Default, PartialEq, Debug)]
+/// struct Provider3;
+///
+/// // Combine them into one:
+/// let forking1 = icu_provider_adapters::make_forking_provider!(
+///     ForkByKeyProvider::new,
+///     [
+///         Provider1::default(),
+///         Provider2::default(),
+///         Provider3::default(),
+///     ]
+/// );
+///
+/// // This is equivalent to:
+/// let forking2 = ForkByKeyProvider::new(
+///     Provider1::default(),
+///     ForkByKeyProvider::new(Provider2::default(), Provider3::default()),
+/// );
+///
+/// assert_eq!(forking1, forking2);
+/// ```
+#[macro_export]
+macro_rules! make_forking_provider {
+    // Base case:
+    ($combo_p:path, [ $a:expr, $b:expr, ]) => {
+        $combo_p($a, $b)
+    };
+    // General list:
+    ($combo_p:path, [ $a:expr, $b:expr, $($c:expr),+, ]) => {
+        $combo_p($a, $crate::make_forking_provider!($combo_p, [ $b, $($c),+, ]))
+    };
+}
+
+#[cfg(test)]
+mod test {
+    #[derive(Default)]
+    struct Provider1;
+    #[derive(Default)]
+    struct Provider2;
+    #[derive(Default)]
+    struct Provider3;
+
+    #[test]
+    fn test_make_forking_provider() {
+        make_forking_provider!(
+            crate::fork::ForkByKeyProvider::new,
+            [
+                Provider1::default(),
+                Provider2::default(),
+                Provider3::default(),
+            ]
+        );
+    }
+}