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// Copyright (c) 2020 Ecma International. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-assignment-operators-runtime-semantics-evaluation
description: >
The LeftHandSideExpression is evaluated before the AssignmentExpression.
features: [logical-assignment-operators]
---*/
function DummyError() { }
assert.throws(DummyError, function() {
var base = null;
var prop = function() {
throw new DummyError();
};
var expr = function() {
throw new Test262Error("right-hand side expression evaluated");
};
base[prop()] ??= expr();
});
assert.throws(TypeError, function() {
var base = null;
var prop = {
toString: function() {
throw new Test262Error("property key evaluated");
}
};
var expr = function() {
throw new Test262Error("right-hand side expression evaluated");
};
base[prop] ??= expr();
});
var count = 0;
var obj = {};
function incr() {
return ++count;
}
assert.sameValue(obj[incr()] ??= incr(), 2, "obj[incr()] ??= incr()");
assert.sameValue(obj[1], 2, "obj[1]");
assert.sameValue(count, 2, "count");
obj[3] = 1;
assert.sameValue(obj[incr()] ??= incr(), 1, "obj[incr()] ??= incr()");
assert.sameValue(obj[3], 1, "obj[3]");
assert.sameValue(count, 3, "count");
reportCompare(0, 0);