1 files changed, 74 insertions, 0 deletions
diff --git a/third_party/rust/tokio/tests/io_read_until.rs b/third_party/rust/tokio/tests/io_read_until.rs
new file mode 100644
index 0000000000..61800a0d9c
--- /dev/null
+++ b/third_party/rust/tokio/tests/io_read_until.rs
@@ -0,0 +1,74 @@
+#![warn(rust_2018_idioms)]
+#![cfg(feature = "full")]
+
+use std::io::ErrorKind;
+use tokio::io::{AsyncBufReadExt, BufReader, Error};
+use tokio_test::{assert_ok, io::Builder};
+
+#[tokio::test]
+async fn read_until() {
+    let mut buf = vec![];
+    let mut rd: &[u8] = b"hello world";
+
+    let n = assert_ok!(rd.read_until(b' ', &mut buf).await);
+    assert_eq!(n, 6);
+    assert_eq!(buf, b"hello ");
+    buf.clear();
+    let n = assert_ok!(rd.read_until(b' ', &mut buf).await);
+    assert_eq!(n, 5);
+    assert_eq!(buf, b"world");
+    buf.clear();
+    let n = assert_ok!(rd.read_until(b' ', &mut buf).await);
+    assert_eq!(n, 0);
+    assert_eq!(buf, []);
+}
+
+#[tokio::test]
+async fn read_until_not_all_ready() {
+    let mock = Builder::new()
+        .read(b"Hello Wor")
+        .read(b"ld#Fizz\xffBuz")
+        .read(b"z#1#2")
+        .build();
+
+    let mut read = BufReader::new(mock);
+
+    let mut chunk = b"We say ".to_vec();
+    let bytes = read.read_until(b'#', &mut chunk).await.unwrap();
+    assert_eq!(bytes, b"Hello World#".len());
+    assert_eq!(chunk, b"We say Hello World#");
+
+    chunk = b"I solve ".to_vec();
+    let bytes = read.read_until(b'#', &mut chunk).await.unwrap();
+    assert_eq!(bytes, b"Fizz\xffBuzz\n".len());
+    assert_eq!(chunk, b"I solve Fizz\xffBuzz#");
+
+    chunk.clear();
+    let bytes = read.read_until(b'#', &mut chunk).await.unwrap();
+    assert_eq!(bytes, 2);
+    assert_eq!(chunk, b"1#");
+
+    chunk.clear();
+    let bytes = read.read_until(b'#', &mut chunk).await.unwrap();
+    assert_eq!(bytes, 1);
+    assert_eq!(chunk, b"2");
+}
+
+#[tokio::test]
+async fn read_until_fail() {
+    let mock = Builder::new()
+        .read(b"Hello \xffWor")
+        .read_error(Error::new(ErrorKind::Other, "The world has no end"))
+        .build();
+
+    let mut read = BufReader::new(mock);
+
+    let mut chunk = b"Foo".to_vec();
+    let err = read
+        .read_until(b'#', &mut chunk)
+        .await
+        .expect_err("Should fail");
+    assert_eq!(err.kind(), ErrorKind::Other);
+    assert_eq!(err.to_string(), "The world has no end");
+    assert_eq!(chunk, b"FooHello \xffWor");
+}