1 files changed, 33 insertions, 0 deletions
diff --git a/std/wasi/testdata/std_fs_file_seek.rs b/std/wasi/testdata/std_fs_file_seek.rs
new file mode 100644
index 000000000..1e2a9d7de
--- /dev/null
+++ b/std/wasi/testdata/std_fs_file_seek.rs
@@ -0,0 +1,33 @@
+// { "preopens": { "/fixture": "fixture" } }
+
+use std::io::Seek;
+
+fn main() {
+  let mut file = std::fs::File::open("/fixture/file").unwrap();
+  assert_eq!(file.seek(std::io::SeekFrom::Current(0)).unwrap(), 0);
+
+  assert_eq!(file.seek(std::io::SeekFrom::Start(1)).unwrap(), 1);
+  assert_eq!(file.seek(std::io::SeekFrom::Start(2)).unwrap(), 2);
+  assert_eq!(file.seek(std::io::SeekFrom::Start(3)).unwrap(), 3);
+  assert_eq!(file.seek(std::io::SeekFrom::Start(4)).unwrap(), 4);
+  assert_eq!(file.seek(std::io::SeekFrom::Start(5)).unwrap(), 5);
+
+  assert_eq!(file.seek(std::io::SeekFrom::Current(-1)).unwrap(), 4);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(-1)).unwrap(), 3);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(-1)).unwrap(), 2);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(-1)).unwrap(), 1);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(-1)).unwrap(), 0);
+
+  assert_eq!(file.seek(std::io::SeekFrom::Current(1)).unwrap(), 1);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(1)).unwrap(), 2);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(1)).unwrap(), 3);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(1)).unwrap(), 4);
+  assert_eq!(file.seek(std::io::SeekFrom::Current(1)).unwrap(), 5);
+
+  assert_eq!(file.seek(std::io::SeekFrom::End(0)).unwrap(), 5);
+  assert_eq!(file.seek(std::io::SeekFrom::End(-1)).unwrap(), 4);
+  assert_eq!(file.seek(std::io::SeekFrom::End(-2)).unwrap(), 3);
+  assert_eq!(file.seek(std::io::SeekFrom::End(-3)).unwrap(), 2);
+  assert_eq!(file.seek(std::io::SeekFrom::End(-4)).unwrap(), 1);
+  assert_eq!(file.seek(std::io::SeekFrom::End(-5)).unwrap(), 0);
+}