1 files changed, 32 insertions, 0 deletions
diff --git a/testing/web-platform/tests/encoding/unsupported-encodings.any.js b/testing/web-platform/tests/encoding/unsupported-encodings.any.js
new file mode 100644
index 0000000000..50c9d07c88
--- /dev/null
+++ b/testing/web-platform/tests/encoding/unsupported-encodings.any.js
@@ -0,0 +1,32 @@
+// META: title=Encoding API: unsupported encodings
+// META: script=resources/decoding-helpers.js
+
+// Attempting to decode '<' as UTF-7 (+AD4) ends up as '+AD4'.
+['UTF-7', 'utf-7'].forEach(label => {
+  decode_test(label, '+AD4', 'U+002B/U+0041/U+0044/U+0034',
+              `${label} should not be supported`);
+});
+
+// UTF-32 will be detected as UTF-16LE if leading BOM, or UTF-8 otherwise (due to XMLHttpRequest).
+['UTF-32', 'utf-32', 'UTF-32LE', 'utf-32le'].forEach(label => {
+  decode_test(label,
+              '%FF%FE%00%00%41%00%00%00%42%00%00%00',
+              'U+0000/U+0041/U+0000/U+0042/U+0000',
+              `${label} with BOM should decode as UTF-16LE`);
+
+  decode_test(label,
+              '%41%00%00%00%42%00%00%C2%80',
+              'U+0041/U+0000/U+0000/U+0000/U+0042/U+0000/U+0000/U+0080',
+              `${label} with no BOM should decode as UTF-8`);;
+});
+['UTF-32be', 'utf-32be'].forEach(label => {
+  decode_test(label,
+            '%00%00%00%41%00%00%00%42%C2%80',
+            'U+0000/U+0000/U+0000/U+0041/U+0000/U+0000/U+0000/U+0042/U+0080',
+            `${label} with no BOM should decode as UTF-8`);
+
+  decode_test(label,
+              '%00%00%FE%FF%00%00%00%41%00%C2%80%42',
+              'U+0000/U+0000/U+FFFD/U+FFFD/U+0000/U+0000/U+0000/U+0041/U+0000/U+0080/U+0042',
+              `${label} with BOM should decode as UTF-8`);
+});