1 files changed, 71 insertions, 0 deletions
diff --git a/cli/tests/unit/fs_events_test.ts b/cli/tests/unit/fs_events_test.ts
new file mode 100644
index 000000000..ad8ba8502
--- /dev/null
+++ b/cli/tests/unit/fs_events_test.ts
@@ -0,0 +1,71 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+import { unitTest, assert } from "./test_util.ts";
+
+// TODO(ry) Add more tests to specify format.
+
+unitTest({ perms: { read: false } }, function watchFsPermissions() {
+  let thrown = false;
+  try {
+    Deno.watchFs(".");
+  } catch (err) {
+    assert(err instanceof Deno.errors.PermissionDenied);
+    thrown = true;
+  }
+  assert(thrown);
+});
+
+unitTest({ perms: { read: true } }, function watchFsInvalidPath() {
+  let thrown = false;
+  try {
+    Deno.watchFs("non-existant.file");
+  } catch (err) {
+    console.error(err);
+    if (Deno.build.os === "windows") {
+      assert(
+        err.message.includes(
+          "Input watch path is neither a file nor a directory"
+        )
+      );
+    } else {
+      assert(err instanceof Deno.errors.NotFound);
+    }
+    thrown = true;
+  }
+  assert(thrown);
+});
+
+async function getTwoEvents(
+  iter: AsyncIterableIterator<Deno.FsEvent>
+): Promise<Deno.FsEvent[]> {
+  const events = [];
+  for await (const event of iter) {
+    events.push(event);
+    if (events.length > 2) break;
+  }
+  return events;
+}
+
+unitTest(
+  { perms: { read: true, write: true } },
+  async function watchFsBasic(): Promise<void> {
+    const testDir = await Deno.makeTempDir();
+    const iter = Deno.watchFs(testDir);
+
+    // Asynchornously capture two fs events.
+    const eventsPromise = getTwoEvents(iter);
+
+    // Make some random file system activity.
+    const file1 = testDir + "/file1.txt";
+    const file2 = testDir + "/file2.txt";
+    Deno.writeFileSync(file1, new Uint8Array([0, 1, 2]));
+    Deno.writeFileSync(file2, new Uint8Array([0, 1, 2]));
+
+    // We should have gotten two fs events.
+    const events = await eventsPromise;
+    assert(events.length >= 2);
+    assert(events[0].kind == "create");
+    assert(events[0].paths[0].includes(testDir));
+    assert(events[1].kind == "create" || events[1].kind == "modify");
+    assert(events[1].paths[0].includes(testDir));
+  }
+);