1 files changed, 51 insertions, 0 deletions
diff --git a/third_party/rust/zerovec/examples/zv_serde.rs b/third_party/rust/zerovec/examples/zv_serde.rs
new file mode 100644
index 0000000000..e4a8ec309b
--- /dev/null
+++ b/third_party/rust/zerovec/examples/zv_serde.rs
@@ -0,0 +1,51 @@
+// 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 ).
+
+// This example demonstrates zero-copy, zero-allocation deserialization of a u32 vector
+// stored in a Bincode buffer.
+
+#![no_main] // https://github.com/unicode-org/icu4x/issues/395
+
+icu_benchmark_macros::static_setup!();
+
+use zerovec::ZeroVec;
+
+#[derive(serde::Serialize, serde::Deserialize)]
+struct DataStruct<'s> {
+    #[serde(borrow)]
+    pub nums: ZeroVec<'s, u16>,
+}
+
+const U16_SLICE: [u16; 16] = [
+    196, 989, 414, 731, 660, 217, 716, 353, 218, 730, 245, 846, 122, 294, 922, 488,
+];
+
+const POSTCARD_BYTES: [u8; 33] = [
+    0x20, 0xc4, 0x0, 0xdd, 0x3, 0x9e, 0x1, 0xdb, 0x2, 0x94, 0x2, 0xd9, 0x0, 0xcc, 0x2, 0x61, 0x1,
+    0xda, 0x0, 0xda, 0x2, 0xf5, 0x0, 0x4e, 0x3, 0x7a, 0x0, 0x26, 0x1, 0x9a, 0x3, 0xe8, 0x1,
+];
+
+#[allow(dead_code)]
+fn serialize() {
+    let data = DataStruct {
+        nums: ZeroVec::from_slice_or_alloc(&U16_SLICE),
+    };
+    let postcard_bytes = postcard::to_stdvec(&data).expect("Serialization should be successful");
+    println!("Postcard bytes: {postcard_bytes:#x?}");
+    println!("ZeroVec bytes: {:#x?}", data.nums.as_bytes());
+}
+
+#[no_mangle]
+fn main(_argc: isize, _argv: *const *const u8) -> isize {
+    icu_benchmark_macros::main_setup!();
+
+    // Un-comment the following line to generate postcard data:
+    // serialize();
+
+    let data: DataStruct = postcard::from_bytes(&POSTCARD_BYTES).expect("Valid bytes");
+    let result = data.nums.iter().sum::<u16>();
+    assert_eq!(8141, result);
+
+    0
+}