1 files changed, 133 insertions, 0 deletions
diff --git a/std/node/stream_test.ts b/std/node/stream_test.ts
new file mode 100644
index 000000000..f8d4ecfa5
--- /dev/null
+++ b/std/node/stream_test.ts
@@ -0,0 +1,133 @@
+// Copyright Node.js contributors. All rights reserved.
+
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+import { Readable, Transform, Writable } from "./stream.ts";
+import { Buffer } from "./buffer.ts";
+import { deferred } from "../async/mod.ts";
+import { assert, assertEquals } from "../testing/asserts.ts";
+import { mustCall } from "./_utils.ts";
+
+Deno.test("Readable and Writable stream backpressure test", async () => {
+  let pushes = 0;
+  const total = 65500 + 40 * 1024;
+
+  let rsExecuted = 0;
+  const rsExecutedExpected = 11;
+  const rsExpectedExecutions = deferred();
+
+  let wsExecuted = 0;
+  const wsExecutedExpected = 410;
+  const wsExpectedExecutions = deferred();
+
+  const rs = new Readable({
+    read: function () {
+      rsExecuted++;
+      if (rsExecuted == rsExecutedExpected) {
+        rsExpectedExecutions.resolve();
+      }
+
+      if (pushes++ === 10) {
+        this.push(null);
+        return;
+      }
+
+      assert(this._readableState.length <= total);
+
+      this.push(Buffer.alloc(65500));
+      for (let i = 0; i < 40; i++) {
+        this.push(Buffer.alloc(1024));
+      }
+    },
+  });
+
+  const ws = new Writable({
+    write: function (_data, _enc, cb) {
+      wsExecuted++;
+      if (wsExecuted == wsExecutedExpected) {
+        wsExpectedExecutions.resolve();
+      }
+      cb();
+    },
+  });
+
+  rs.pipe(ws);
+
+  const rsTimeout = setTimeout(() => rsExpectedExecutions.reject(), 1000);
+  const wsTimeout = setTimeout(() => wsExpectedExecutions.reject(), 1000);
+  await rsExpectedExecutions;
+  await wsExpectedExecutions;
+  clearTimeout(rsTimeout);
+  clearTimeout(wsTimeout);
+  assertEquals(rsExecuted, rsExecutedExpected);
+  assertEquals(wsExecuted, wsExecutedExpected);
+});
+
+Deno.test("Readable can be piped through Transform", async () => {
+  const [readExecution, readCb] = mustCall(function (this: Readable) {
+    this.push("content");
+    this.push(null);
+  });
+
+  const r = new Readable({
+    read: readCb,
+  });
+
+  const [transformExecution, transformCb] = mustCall(
+    function (
+      this: Transform,
+      chunk: unknown,
+      _e,
+      callback: (error?: Error | null) => void,
+    ) {
+      this.push(chunk);
+      callback();
+    },
+  );
+
+  const [flushExecution, flushCb] = mustCall(
+    function (this: Transform, callback: (error?: Error | null) => void) {
+      callback();
+    },
+  );
+
+  const t = new Transform({
+    transform: transformCb,
+    flush: flushCb,
+  });
+
+  r.pipe(t);
+
+  const [readableExecution, readableCb] = mustCall(function () {
+    while (true) {
+      const chunk = t.read();
+      if (!chunk) {
+        break;
+      }
+
+      assertEquals(chunk.toString(), "content");
+    }
+  }, 2);
+
+  t.on("readable", readableCb);
+
+  await readExecution;
+  await transformExecution;
+  await flushExecution;
+  await readableExecution;
+});