Import wpt@40665266227e475bc4a56884247d8c09d78dfb6a

third_party/WebKit/LayoutTests/external/wpt/streams/piping/transform-streams.js

+'use strict';
+
+if (self.importScripts) {
+  self.importScripts('/resources/testharness.js');
+}
+
+promise_test(() => {
+  const rs = new ReadableStream({
+    start(c) {
+      c.enqueue('a');
+      c.enqueue('b');
+      c.enqueue('c');
+      c.close();
+    }
+  });
+
+  const ts = new TransformStream();
+
+  const ws = new WritableStream();
+
+  return rs.pipeThrough(ts).pipeTo(ws).then(() => {
+    const writer = ws.getWriter();
+    return writer.closed;
+  });
+}, 'Piping through an identity transform stream should close the destination when the source closes');
+
+done();