text: // Copyright Joyent, Inc. and other Node contributors.
  //
  // 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.
  
  var common = require('../common');
  var assert = require('assert');
  var stream = require('stream');
  var str = 'asdfasdfasdfasdfasdf';
  
  var r = new stream.Readable({
    highWaterMark: 5,
    encoding: 'utf8'
  });
  
  var reads = 0;
  var eofed = false;
  var ended = false;
  
  r._read = function(n, cb) {
    if (reads === 0) {
      setTimeout(function() {
        cb(null, str);
      });
      reads++;
    } else if (reads === 1) {
      var ret = r.push(str);
      assert.equal(ret, false);
      reads++;
    } else {
      assert(!eofed);
      eofed = true;
      cb(null, null);
    }
  };
  
  r.on('end', function() {
    ended = true;
  });
  
  // push some data in to start.
  // we've never gotten any read event at this point.
  var ret = r.push(str);
  // should be false.  > hwm
  assert(!ret);
  var chunk = r.read();
  assert.equal(chunk, str);
  chunk = r.read();
  assert.equal(chunk, null);
  
  r.once('readable', function() {
    // this time, we'll get *all* the remaining data, because
    // it's been added synchronously, as the read WOULD take
    // us below the hwm, and so it triggered a _read() again,
    // which synchronously added more, which we then return.
    chunk = r.read();
    assert.equal(chunk, str + str);
  
    chunk = r.read();
    assert.equal(chunk, null);
  });
  
  process.on('exit', function() {
    assert(eofed);
    assert(ended);
    assert.equal(reads, 2);
    console.log('ok');
  });
  