gecko/xpcom/tests/unit/test_seek_multiplex.js

/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

const Ci = Components.interfaces;
const Cr = Components.results;
const CC = Components.Constructor;
const Cc = Components.classes;

// The string we use as data.
const data = "0123456789";
// Number of streams in the multiplex stream.
const count = 10;

function test_multiplex_streams() {
  try {
    var MultiplexStream = CC("@mozilla.org/io/multiplex-input-stream;1",
                             "nsIMultiplexInputStream");
                             do_check_eq(1, 1);

    var BinaryInputStream = Components.Constructor("@mozilla.org/binaryinputstream;1",
                                                   "nsIBinaryInputStream");
    var BinaryOutputStream = Components.Constructor("@mozilla.org/binaryoutputstream;1",
                                                    "nsIBinaryOutputStream",
                                                    "setOutputStream");
    var multiplex = new MultiplexStream();
    for (var i = 0; i < count; ++i) {
      let s = Cc["@mozilla.org/io/string-input-stream;1"]
                .createInstance(Ci.nsIStringInputStream);
      s.setData(data, data.length);

      multiplex.appendStream(s);
    }
    var seekable = multiplex.QueryInterface(Ci.nsISeekableStream);
    var sis = Cc["@mozilla.org/scriptableinputstream;1"]
                .createInstance(Ci.nsIScriptableInputStream);
    sis.init(seekable);
    // Read some data.
    var readData = sis.read(20);
    do_check_eq(readData, data + data);
    // -- Tests for NS_SEEK_SET
    // Seek accross stream.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 35);
    do_check_eq(seekable.tell(), 35);
    do_check_eq(seekable.available(), 65);
    readData = sis.read(5);
    do_check_eq(readData, data.slice(5));
    do_check_eq(seekable.available(), 60);
    // Seek at stream boundaries.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 40);
    do_check_eq(seekable.tell(), 40);
    do_check_eq(seekable.available(), 60);
    readData = sis.read(10);
    do_check_eq(readData, data);
    do_check_eq(seekable.tell(), 50);
    do_check_eq(seekable.available(), 50);
    // Rewind and read accross streams.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 39);
    do_check_eq(seekable.tell(), 39);
    do_check_eq(seekable.available(), 61);
    readData = sis.read(11);
    do_check_eq(readData, data.slice(9) + data);
    do_check_eq(seekable.tell(), 50);
    do_check_eq(seekable.available(), 50);
    // Rewind to the beginning.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 0);
    do_check_eq(seekable.tell(), 0);
    do_check_eq(seekable.available(), 100);
    // Seek to some randome location
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 50);
    // -- Tests for NS_SEEK_CUR
    // Positive seek.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_CUR, 15);
    do_check_eq(seekable.tell(), 65);
    do_check_eq(seekable.available(), 35);
    readData = sis.read(10);
    do_check_eq(readData, data.slice(5) + data.slice(0, 5));
    do_check_eq(seekable.tell(), 75);
    do_check_eq(seekable.available(), 25);
    // Negative seek.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_CUR, -15);
    do_check_eq(seekable.tell(), 60);
    do_check_eq(seekable.available(), 40);
    readData = sis.read(10);
    do_check_eq(readData, data);
    do_check_eq(seekable.tell(), 70);
    do_check_eq(seekable.available(), 30);

    // -- Tests for NS_SEEK_END
    // Normal read.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_END, -5);
    do_check_eq(seekable.tell(), data.length * count - 5);
    readData = sis.read(5);
    do_check_eq(readData, data.slice(5));
    do_check_eq(seekable.tell(), data.length * count);
    // Read accros streams.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_END, -15);
    do_check_eq(seekable.tell(), data.length * count - 15);
    readData = sis.read(15);
    do_check_eq(readData, data.slice(5) + data);
    do_check_eq(seekable.tell(), data.length * count);

    // -- Try to do various edge cases
    // Forward seek from the end, should throw.
    var caught = false;
    try {
      seekable.seek(Ci.nsISeekableStream.NS_SEEK_END, 15);
    } catch(e) {
      caught = true;
    }
    do_check_eq(caught, true);
    do_check_eq(seekable.tell(), data.length * count);
    // Backward seek from the beginning, should be clamped.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 0);
    do_check_eq(seekable.tell(), 0);
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_CUR, -15);
    do_check_eq(seekable.tell(), 0);
    // Seek too far: shoul be clamped.
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 0);
    do_check_eq(seekable.tell(), 0);
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_CUR, 3 * data.length * count);
    do_check_eq(seekable.tell(), 100);
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, data.length * count);
    do_check_eq(seekable.tell(), 100);
    seekable.seek(Ci.nsISeekableStream.NS_SEEK_CUR, -2 * data.length * count);
    do_check_eq(seekable.tell(), 0);
  } catch(e) {
    dump(e + "\n");
  }
}

function test_multiplex_bug797871() {

  var data = "1234567890123456789012345678901234567890";

  try {
    var MultiplexStream = CC("@mozilla.org/io/multiplex-input-stream;1",
                             "nsIMultiplexInputStream");
    do_check_eq(1, 1);

    var BinaryInputStream = Components.Constructor("@mozilla.org/binaryinputstream;1",
                                                   "nsIBinaryInputStream");
    var BinaryOutputStream = Components.Constructor("@mozilla.org/binaryoutputstream;1",
                                                    "nsIBinaryOutputStream",
                                                    "setOutputStream");
    var multiplex = new MultiplexStream();
    let s = Cc["@mozilla.org/io/string-input-stream;1"]
              .createInstance(Ci.nsIStringInputStream);
    s.setData(data, data.length);

    multiplex.appendStream(s);

    var seekable = multiplex.QueryInterface(Ci.nsISeekableStream);
    var sis = Cc["@mozilla.org/scriptableinputstream;1"]
                .createInstance(Ci.nsIScriptableInputStream);
    sis.init(seekable);

    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 8);
    do_check_eq(seekable.tell(), 8);
    readData = sis.read(2);
    do_check_eq(seekable.tell(), 10);

    seekable.seek(Ci.nsISeekableStream.NS_SEEK_SET, 20);
    do_check_eq(seekable.tell(), 20);
  } catch(e) {
    do_note_exception(e, "exception in test_multiplex_bug797871");
  }
}

function run_test() {
  test_multiplex_streams();
  test_multiplex_bug797871();
}