2 files changed, 39 insertions, 0 deletions
diff --git a/cli/tests/unit/sync_test.ts b/cli/tests/unit/sync_test.ts
new file mode 100644
index 000000000..7a489e951
--- /dev/null
+++ b/cli/tests/unit/sync_test.ts
@@ -0,0 +1,38 @@
+// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
+import { unitTest, assertEquals } from "./test_util.ts";
+
+unitTest(
+  { perms: { read: true, write: true } },
+  function fsyncSyncSuccess(): void {
+    const filename = Deno.makeTempDirSync() + "/test_fsyncSync.txt";
+    const file = Deno.openSync(filename, {
+      read: true,
+      write: true,
+      create: true,
+    });
+    const size = 64;
+    Deno.ftruncateSync(file.rid, size);
+    Deno.fsyncSync(file.rid);
+    assertEquals(Deno.statSync(filename).size, size);
+    Deno.close(file.rid);
+    Deno.removeSync(filename);
+  }
+);
+
+unitTest(
+  { perms: { read: true, write: true } },
+  async function fsyncSuccess(): Promise<void> {
+    const filename = (await Deno.makeTempDir()) + "/test_fsync.txt";
+    const file = await Deno.open(filename, {
+      read: true,
+      write: true,
+      create: true,
+    });
+    const size = 64;
+    await Deno.ftruncate(file.rid, size);
+    await Deno.fsync(file.rid);
+    assertEquals((await Deno.stat(filename)).size, size);
+    Deno.close(file.rid);
+    await Deno.remove(filename);
+  }
+);
diff --git a/cli/tests/unit/unit_tests.ts b/cli/tests/unit/unit_tests.ts
index b16141bdc..1701170d1 100644
--- a/cli/tests/unit/unit_tests.ts
+++ b/cli/tests/unit/unit_tests.ts
@@ -59,6 +59,7 @@ import "./streams_piping_test.ts";
 import "./streams_transform_test.ts";
 import "./streams_writable_test.ts";
 import "./symlink_test.ts";
+import "./sync_test.ts";
 import "./text_encoding_test.ts";
 import "./testing_test.ts";
 import "./timers_test.ts";