Bug 730765 - Tests for nsISeekableStream when backed by a nsMultiplexInputStream. r=biesi

xpcom/tests/unit/test_seek_multiplex.js

@@ -0,0 +1,135 @@
+/* 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 run_test() {
+  test_multiplex_streams();
+}
+

xpcom/tests/unit/xpcshell.ini

@@ -35,6 +35,7 @@ skip-if = os == "win" # See bug: 676412
 [test_pipe.js]
 [test_storagestream.js]
 [test_streams.js]
+[test_seek_multiplex.js]
 [test_stringstream.js]
 [test_symlinks.js]
 # Bug 676998: test fails consistently on Android