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diff --git a/js/src/tests/test262/annexB/language/expressions/equals/emulates-undefined.js b/js/src/tests/test262/annexB/language/expressions/equals/emulates-undefined.js
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index 0000000000..ca0a8805f1
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+++ b/js/src/tests/test262/annexB/language/expressions/equals/emulates-undefined.js
@@ -0,0 +1,32 @@
+// Copyright (C) 2020 Alexey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-equality-operators-runtime-semantics-evaluation
+description: >
+  Abstract Equality special-cases [[IsHTMLDDA]] objects with `undefined` and `null`.
+info: |
+  EqualityExpression : EqualityExpression == RelationalExpression
+
+  [...]
+  5. Return the result of performing Abstract Equality Comparison rval == lval.
+
+  The [[IsHTMLDDA]] Internal Slot / Changes to Abstract Equality Comparison
+
+  The following steps are inserted after step 3 of the Abstract Equality Comparison algorithm:
+
+  1. If Type(x) is Object and x has an [[IsHTMLDDA]] internal slot and y is either null or undefined, return true.
+  2. If x is either null or undefined and Type(y) is Object and y has an [[IsHTMLDDA]] internal slot, return true.
+features: [IsHTMLDDA]
+---*/
+
+var IsHTMLDDA = $262.IsHTMLDDA;
+
+assert(IsHTMLDDA == undefined, "== with `undefined`");
+assert(undefined == IsHTMLDDA, "== with `undefined`");
+
+assert(IsHTMLDDA == null, "== with `null`");
+assert(null == IsHTMLDDA, "== with `null`");
+
+assert(IsHTMLDDA == IsHTMLDDA);
+
+reportCompare(0, 0);