1 files changed, 177 insertions, 0 deletions
diff --git a/third_party/rust/bytes/tests/test_chain.rs b/third_party/rust/bytes/tests/test_chain.rs
new file mode 100644
index 0000000000..cfda6b8dc7
--- /dev/null
+++ b/third_party/rust/bytes/tests/test_chain.rs
@@ -0,0 +1,177 @@
+#![warn(rust_2018_idioms)]
+
+use bytes::{Buf, BufMut, Bytes};
+#[cfg(feature = "std")]
+use std::io::IoSlice;
+
+#[test]
+fn collect_two_bufs() {
+    let a = Bytes::from(&b"hello"[..]);
+    let b = Bytes::from(&b"world"[..]);
+
+    let res = a.chain(b).copy_to_bytes(10);
+    assert_eq!(res, &b"helloworld"[..]);
+}
+
+#[test]
+fn writing_chained() {
+    let mut a = [0u8; 64];
+    let mut b = [0u8; 64];
+
+    {
+        let mut buf = (&mut a[..]).chain_mut(&mut b[..]);
+
+        for i in 0u8..128 {
+            buf.put_u8(i);
+        }
+    }
+
+    for i in 0..64 {
+        let expect = i as u8;
+        assert_eq!(expect, a[i]);
+        assert_eq!(expect + 64, b[i]);
+    }
+}
+
+#[test]
+fn iterating_two_bufs() {
+    let a = Bytes::from(&b"hello"[..]);
+    let b = Bytes::from(&b"world"[..]);
+
+    let res: Vec<u8> = a.chain(b).into_iter().collect();
+    assert_eq!(res, &b"helloworld"[..]);
+}
+
+#[cfg(feature = "std")]
+#[test]
+fn vectored_read() {
+    let a = Bytes::from(&b"hello"[..]);
+    let b = Bytes::from(&b"world"[..]);
+
+    let mut buf = a.chain(b);
+
+    {
+        let b1: &[u8] = &mut [];
+        let b2: &[u8] = &mut [];
+        let b3: &[u8] = &mut [];
+        let b4: &[u8] = &mut [];
+        let mut iovecs = [
+            IoSlice::new(b1),
+            IoSlice::new(b2),
+            IoSlice::new(b3),
+            IoSlice::new(b4),
+        ];
+
+        assert_eq!(2, buf.chunks_vectored(&mut iovecs));
+        assert_eq!(iovecs[0][..], b"hello"[..]);
+        assert_eq!(iovecs[1][..], b"world"[..]);
+        assert_eq!(iovecs[2][..], b""[..]);
+        assert_eq!(iovecs[3][..], b""[..]);
+    }
+
+    buf.advance(2);
+
+    {
+        let b1: &[u8] = &mut [];
+        let b2: &[u8] = &mut [];
+        let b3: &[u8] = &mut [];
+        let b4: &[u8] = &mut [];
+        let mut iovecs = [
+            IoSlice::new(b1),
+            IoSlice::new(b2),
+            IoSlice::new(b3),
+            IoSlice::new(b4),
+        ];
+
+        assert_eq!(2, buf.chunks_vectored(&mut iovecs));
+        assert_eq!(iovecs[0][..], b"llo"[..]);
+        assert_eq!(iovecs[1][..], b"world"[..]);
+        assert_eq!(iovecs[2][..], b""[..]);
+        assert_eq!(iovecs[3][..], b""[..]);
+    }
+
+    buf.advance(3);
+
+    {
+        let b1: &[u8] = &mut [];
+        let b2: &[u8] = &mut [];
+        let b3: &[u8] = &mut [];
+        let b4: &[u8] = &mut [];
+        let mut iovecs = [
+            IoSlice::new(b1),
+            IoSlice::new(b2),
+            IoSlice::new(b3),
+            IoSlice::new(b4),
+        ];
+
+        assert_eq!(1, buf.chunks_vectored(&mut iovecs));
+        assert_eq!(iovecs[0][..], b"world"[..]);
+        assert_eq!(iovecs[1][..], b""[..]);
+        assert_eq!(iovecs[2][..], b""[..]);
+        assert_eq!(iovecs[3][..], b""[..]);
+    }
+
+    buf.advance(3);
+
+    {
+        let b1: &[u8] = &mut [];
+        let b2: &[u8] = &mut [];
+        let b3: &[u8] = &mut [];
+        let b4: &[u8] = &mut [];
+        let mut iovecs = [
+            IoSlice::new(b1),
+            IoSlice::new(b2),
+            IoSlice::new(b3),
+            IoSlice::new(b4),
+        ];
+
+        assert_eq!(1, buf.chunks_vectored(&mut iovecs));
+        assert_eq!(iovecs[0][..], b"ld"[..]);
+        assert_eq!(iovecs[1][..], b""[..]);
+        assert_eq!(iovecs[2][..], b""[..]);
+        assert_eq!(iovecs[3][..], b""[..]);
+    }
+}
+
+#[test]
+fn chain_growing_buffer() {
+    let mut buff = [' ' as u8; 10];
+    let mut vec = b"wassup".to_vec();
+
+    let mut chained = (&mut buff[..]).chain_mut(&mut vec).chain_mut(Vec::new()); // Required for potential overflow because remaining_mut for Vec is isize::MAX - vec.len(), but for chain_mut is usize::MAX
+
+    chained.put_slice(b"hey there123123");
+
+    assert_eq!(&buff, b"hey there1");
+    assert_eq!(&vec, b"wassup23123");
+}
+
+#[test]
+fn chain_overflow_remaining_mut() {
+    let mut chained = Vec::<u8>::new().chain_mut(Vec::new()).chain_mut(Vec::new());
+
+    assert_eq!(chained.remaining_mut(), usize::MAX);
+    chained.put_slice(&[0; 256]);
+    assert_eq!(chained.remaining_mut(), usize::MAX);
+}
+
+#[test]
+fn chain_get_bytes() {
+    let mut ab = Bytes::copy_from_slice(b"ab");
+    let mut cd = Bytes::copy_from_slice(b"cd");
+    let ab_ptr = ab.as_ptr();
+    let cd_ptr = cd.as_ptr();
+    let mut chain = (&mut ab).chain(&mut cd);
+    let a = chain.copy_to_bytes(1);
+    let bc = chain.copy_to_bytes(2);
+    let d = chain.copy_to_bytes(1);
+
+    assert_eq!(Bytes::copy_from_slice(b"a"), a);
+    assert_eq!(Bytes::copy_from_slice(b"bc"), bc);
+    assert_eq!(Bytes::copy_from_slice(b"d"), d);
+
+    // assert `get_bytes` did not allocate
+    assert_eq!(ab_ptr, a.as_ptr());
+    // assert `get_bytes` did not allocate
+    assert_eq!(cd_ptr.wrapping_offset(1), d.as_ptr());
+}