Function testDropNewestDiscards

test/parallel/test-stream-iter-writable-interop.js:186–207

()

// =============================================================================

async function testDropNewestDiscards() {
  const chunks = [];
  const writable = new Writable({
    highWaterMark: 5,
    write(chunk, enc, cb) {
      chunks.push(Buffer.from(chunk));
      // Never call cb -- data stays buffered
    },
  });

  const writer = fromWritable(writable, { backpressure: 'drop-newest' });

  // First write fills the buffer
  await writer.write('12345');

  // Second write should be silently discarded (no reject, no block)
  await writer.write('dropped');

  // Only the first chunk was actually written to the writable
  assert.strictEqual(chunks.length, 1);
  assert.strictEqual(chunks[0].toString(), '12345');
}

// =============================================================================
// drop-newest: writev discards entire batch when full