Vendor things

third-party/vendor/zerocopy-derive/tests/struct_from_bytes.rs

@@ -0,0 +1,79 @@
+// Copyright 2019 The Fuchsia Authors
+//
+// Licensed under a BSD-style license <LICENSE-BSD>, Apache License, Version 2.0
+// <LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0>, or the MIT
+// license <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your option.
+// This file may not be copied, modified, or distributed except according to
+// those terms.
+
+#![allow(warnings)]
+
+mod util;
+
+use std::{marker::PhantomData, option::IntoIter};
+
+use {
+    static_assertions::assert_impl_all,
+    zerocopy::{FromBytes, FromZeroes},
+};
+
+use crate::util::AU16;
+
+// A struct is `FromBytes` if:
+// - all fields are `FromBytes`
+
+#[derive(FromZeroes, FromBytes)]
+struct Zst;
+
+assert_impl_all!(Zst: FromBytes);
+
+#[derive(FromZeroes, FromBytes)]
+struct One {
+    a: u8,
+}
+
+assert_impl_all!(One: FromBytes);
+
+#[derive(FromZeroes, FromBytes)]
+struct Two {
+    a: u8,
+    b: Zst,
+}
+
+assert_impl_all!(Two: FromBytes);
+
+#[derive(FromZeroes, FromBytes)]
+struct Unsized {
+    a: [u8],
+}
+
+assert_impl_all!(Unsized: FromBytes);
+
+#[derive(FromZeroes, FromBytes)]
+struct TypeParams<'a, T: ?Sized, I: Iterator> {
+    a: I::Item,
+    b: u8,
+    c: PhantomData<&'a [u8]>,
+    d: PhantomData<&'static str>,
+    e: PhantomData<String>,
+    f: T,
+}
+
+assert_impl_all!(TypeParams<'static, (), IntoIter<()>>: FromBytes);
+assert_impl_all!(TypeParams<'static, AU16, IntoIter<()>>: FromBytes);
+assert_impl_all!(TypeParams<'static, [AU16], IntoIter<()>>: FromBytes);
+
+// Deriving `FromBytes` should work if the struct has bounded parameters.
+
+#[derive(FromZeroes, FromBytes)]
+#[repr(transparent)]
+struct WithParams<'a: 'b, 'b: 'a, const N: usize, T: 'a + 'b + FromBytes>(
+    [T; N],
+    PhantomData<&'a &'b ()>,
+)
+where
+    'a: 'b,
+    'b: 'a,
+    T: 'a + 'b + FromBytes;
+
+assert_impl_all!(WithParams<'static, 'static, 42, u8>: FromBytes);