1 files changed, 227 insertions, 0 deletions
diff --git a/dom/encoding/test/unit/test_utf.js b/dom/encoding/test/unit/test_utf.js
new file mode 100644
index 0000000000..b824d30377
--- /dev/null
+++ b/dom/encoding/test/unit/test_utf.js
@@ -0,0 +1,227 @@
+// NOTE: Requires testharness.js
+// http://www.w3.org/2008/webapps/wiki/Harness
+
+// Extension to testharness.js API which avoids logging enormous strings
+// on a coding failure.
+function assert_string_equals(actual, expected, description) {
+  // short circuit success case
+  if (actual === expected) {
+    assert_true(true, description + ": <actual> === <expected>");
+    return;
+  }
+
+  // length check
+  assert_equals(
+    actual.length,
+    expected.length,
+    description + ": string lengths"
+  );
+
+  var i, a, b;
+  for (i = 0; i < actual.length; i++) {
+    a = actual.charCodeAt(i);
+    b = expected.charCodeAt(i);
+    if (a !== b) {
+      assert_true(
+        false,
+        description +
+          ": code unit " +
+          i.toString() +
+          " unequal: " +
+          cpname(a) +
+          " != " +
+          cpname(b)
+      );
+    } // doesn't return
+  }
+
+  // It should be impossible to get here, because the initial
+  // comparison failed, so either the length comparison or the
+  // codeunit-by-codeunit comparison should also fail.
+  assert_true(false, description + ": failed to detect string difference");
+}
+
+// Inspired by:
+// http://ecmanaut.blogspot.com/2006/07/encoding-decoding-utf8-in-javascript.html
+function encode_utf8(string) {
+  var utf8 = unescape(encodeURIComponent(string));
+  var octets = new Uint8Array(utf8.length),
+    i;
+  for (i = 0; i < utf8.length; i += 1) {
+    octets[i] = utf8.charCodeAt(i);
+  }
+  return octets;
+}
+
+function encode_utf16le(string) {
+  var octets = new Uint8Array(string.length * 2);
+  var di = 0;
+  for (var i = 0; i < string.length; i++) {
+    var code = string.charCodeAt(i);
+    octets[di++] = code & 0xff;
+    octets[di++] = code >> 8;
+  }
+  return octets;
+}
+
+function encode_utf16be(string) {
+  var octets = new Uint8Array(string.length * 2);
+  var di = 0;
+  for (var i = 0; i < string.length; i++) {
+    var code = string.charCodeAt(i);
+    octets[di++] = code >> 8;
+    octets[di++] = code & 0xff;
+  }
+  return octets;
+}
+
+function decode_utf8(octets) {
+  var utf8 = String.fromCharCode.apply(null, octets);
+  return decodeURIComponent(escape(utf8));
+}
+
+// Helpers for test_utf_roundtrip.
+function cpname(n) {
+  if (n + 0 !== n) {
+    return n.toString();
+  }
+  var w = n <= 0xffff ? 4 : 6;
+  return "U+" + ("000000" + n.toString(16).toUpperCase()).slice(-w);
+}
+
+function genblock(from, len) {
+  var i, j, point, offset;
+  var size, block;
+
+  // determine size required:
+  //    1 unit   for each point from U+000000 through U+00D7FF
+  //    0 units                      U+00D800 through U+00DFFF
+  //    1 unit                       U+00E000 through U+00FFFF
+  //    2 units                      U+010000 through U+10FFFF
+  function overlap(min1, max1, min2, max2) {
+    return Math.max(0, Math.min(max1, max2) - Math.max(min1, min2));
+  }
+  size =
+    overlap(from, from + len, 0x000000, 0x00d800) +
+    overlap(from, from + len, 0x00e000, 0x010000) +
+    overlap(from, from + len, 0x010000, 0x110000) * 2;
+
+  block = new Uint16Array(size);
+  for (i = 0, j = 0; i < len; i++) {
+    point = from + i;
+    if (0xd800 <= point && point <= 0xdfff) {
+      continue;
+    } else if (point <= 0xffff) {
+      block[j++] = point;
+    } else {
+      offset = point - 0x10000;
+      block[j++] = 0xd800 + (offset >> 10);
+      block[j++] = 0xdc00 + (offset & 0x3ff);
+    }
+  }
+  return String.fromCharCode.apply(null, block);
+}
+
+function test_utf_roundtrip() {
+  var MIN_CODEPOINT = 0;
+  var MAX_CODEPOINT = 0x10ffff;
+  var BLOCK_SIZE = 0x1000;
+
+  var block, block_tag, i, j, encoded, decoded, exp_encoded, exp_decoded;
+
+  var TD_U16LE = new TextDecoder("UTF-16LE");
+
+  var TD_U16BE = new TextDecoder("UTF-16BE");
+
+  var TE_U8 = new TextEncoder();
+  var TD_U8 = new TextDecoder("UTF-8");
+
+  for (i = MIN_CODEPOINT; i < MAX_CODEPOINT; i += BLOCK_SIZE) {
+    block_tag = cpname(i) + " - " + cpname(i + BLOCK_SIZE - 1);
+    block = genblock(i, BLOCK_SIZE);
+
+    // test UTF-16LE, UTF-16BE, and UTF-8 encodings against themselves
+    encoded = encode_utf16le(block);
+    decoded = TD_U16LE.decode(encoded);
+    assert_string_equals(block, decoded, "UTF-16LE round trip " + block_tag);
+
+    encoded = encode_utf16be(block);
+    decoded = TD_U16BE.decode(encoded);
+    assert_string_equals(block, decoded, "UTF-16BE round trip " + block_tag);
+
+    encoded = TE_U8.encode(block);
+    decoded = TD_U8.decode(encoded);
+    assert_string_equals(block, decoded, "UTF-8 round trip " + block_tag);
+
+    // test TextEncoder(UTF-8) against the older idiom
+    exp_encoded = encode_utf8(block);
+    assert_array_equals(
+      encoded,
+      exp_encoded,
+      "UTF-8 reference encoding " + block_tag
+    );
+
+    exp_decoded = decode_utf8(exp_encoded);
+    assert_string_equals(
+      decoded,
+      exp_decoded,
+      "UTF-8 reference decoding " + block_tag
+    );
+  }
+}
+
+function test_utf_samples() {
+  // z, cent, CJK water, G-Clef, Private-use character
+  var sample = "z\xA2\u6C34\uD834\uDD1E\uDBFF\uDFFD";
+  var cases = [
+    {
+      encoding: "utf-8",
+      expected: [
+        0x7a, 0xc2, 0xa2, 0xe6, 0xb0, 0xb4, 0xf0, 0x9d, 0x84, 0x9e, 0xf4, 0x8f,
+        0xbf, 0xbd,
+      ],
+    },
+    {
+      encoding: "utf-16le",
+      expected: [
+        0x7a, 0x00, 0xa2, 0x00, 0x34, 0x6c, 0x34, 0xd8, 0x1e, 0xdd, 0xff, 0xdb,
+        0xfd, 0xdf,
+      ],
+    },
+    {
+      encoding: "utf-16",
+      expected: [
+        0x7a, 0x00, 0xa2, 0x00, 0x34, 0x6c, 0x34, 0xd8, 0x1e, 0xdd, 0xff, 0xdb,
+        0xfd, 0xdf,
+      ],
+    },
+    {
+      encoding: "utf-16be",
+      expected: [
+        0x00, 0x7a, 0x00, 0xa2, 0x6c, 0x34, 0xd8, 0x34, 0xdd, 0x1e, 0xdb, 0xff,
+        0xdf, 0xfd,
+      ],
+    },
+  ];
+
+  var encoded = new TextEncoder().encode(sample);
+  assert_array_equals(encoded, cases[0].expected, "expected equal encodings");
+
+  cases.forEach(function (t) {
+    var decoded = new TextDecoder(t.encoding).decode(
+      new Uint8Array(t.expected)
+    );
+    assert_equals(decoded, sample, "expected equal decodings - " + t.encoding);
+  });
+}
+
+test(
+  test_utf_samples,
+  "UTF-8, UTF-16LE, UTF-16BE - Encode/Decode - reference sample"
+);
+
+test(
+  test_utf_roundtrip,
+  "UTF-8, UTF-16LE, UTF-16BE - Encode/Decode - full roundtrip and " +
+    "agreement with encode/decodeURIComponent"
+);