feat(std/wasi): implement fd_datasync (#6556)

1 files changed, 15 insertions, 0 deletions

diff --git a/std/wasi/testdata/std_fs_file_sync_data.rs b/std/wasi/testdata/std_fs_file_sync_data.rs
new file mode 100644
index 000000000..f19f8e9b7
--- /dev/null
+++ b/std/wasi/testdata/std_fs_file_sync_data.rs
@@ -0,0 +1,15 @@
+// { "preopens": { "/scratch": "scratch" } }
+
+use std::io::Write;
+
+fn main() {
+  let mut file = std::fs::File::create("/scratch/file").unwrap();
+
+  assert!(file.write(b"Hello").is_ok());
+  assert!(file.sync_data().is_ok());
+  assert_eq!(std::fs::read("/scratch/file").unwrap(), b"Hello");
+
+  assert!(file.write(b", world!").is_ok());
+  assert!(file.sync_data().is_ok());
+  assert_eq!(std::fs::read("/scratch/file").unwrap(), b"Hello, world!");
+}