1 files changed, 42 insertions, 0 deletions
diff --git a/testing/web-platform/tests/encoding/textdecoder-byte-order-marks.any.js b/testing/web-platform/tests/encoding/textdecoder-byte-order-marks.any.js
new file mode 100644
index 0000000000..9ef0d73141
--- /dev/null
+++ b/testing/web-platform/tests/encoding/textdecoder-byte-order-marks.any.js
@@ -0,0 +1,42 @@
+// META: title=Encoding API: Byte-order marks
+
+var testCases = [
+    {
+        encoding: 'utf-8',
+        bom: [0xEF, 0xBB, 0xBF],
+        bytes: [0x7A, 0xC2, 0xA2, 0xE6, 0xB0, 0xB4, 0xF0, 0x9D, 0x84, 0x9E, 0xF4, 0x8F, 0xBF, 0xBD]
+    },
+    {
+        encoding: 'utf-16le',
+        bom: [0xff, 0xfe],
+        bytes: [0x7A, 0x00, 0xA2, 0x00, 0x34, 0x6C, 0x34, 0xD8, 0x1E, 0xDD, 0xFF, 0xDB, 0xFD, 0xDF]
+    },
+    {
+        encoding: 'utf-16be',
+        bom: [0xfe, 0xff],
+        bytes: [0x00, 0x7A, 0x00, 0xA2, 0x6C, 0x34, 0xD8, 0x34, 0xDD, 0x1E, 0xDB, 0xFF, 0xDF, 0xFD]
+    }
+];
+
+var string = 'z\xA2\u6C34\uD834\uDD1E\uDBFF\uDFFD'; // z, cent, CJK water, G-Clef, Private-use character
+
+testCases.forEach(function(t) {
+    test(function() {
+
+        var decoder = new TextDecoder(t.encoding);
+        assert_equals(decoder.decode(new Uint8Array(t.bytes)), string,
+                      'Sequence without BOM should decode successfully');
+
+        assert_equals(decoder.decode(new Uint8Array(t.bom.concat(t.bytes))), string,
+                      'Sequence with BOM should decode successfully (with no BOM present in output)');
+
+        testCases.forEach(function(o) {
+            if (o === t)
+                return;
+
+            assert_not_equals(decoder.decode(new Uint8Array(o.bom.concat(t.bytes))), string,
+                              'Mismatching BOM should not be ignored - treated as garbage bytes.');
+        });
+
+    }, 'Byte-order marks: ' + t.encoding);
+});