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// Copyright (C) 2016 The V8 Project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 18.2.3
esid: sec-isnan-number
description: >
Use non-object value returned from @@toPrimitive method
info: |
isNaN (number)
1. Let num be ? ToNumber(number).
ToPrimitive ( input [ , PreferredType ] )
[...]
4. Let exoticToPrim be ? GetMethod(input, @@toPrimitive).
5. If exoticToPrim is not undefined, then
a. Let result be ? Call(exoticToPrim, input, « hint »).
b. If Type(result) is not Object, return result.
features: [Symbol.toPrimitive]
---*/
var called = 0;
var obj = {
valueOf: function() {
called = NaN;
return Infinity;
},
toString: function() {
called = NaN;
return Infinity;
}
};
obj[Symbol.toPrimitive] = function() {
called += 1;
return 42;
};
assert.sameValue(isNaN(obj), false, "use returned value - non-NaN number");
assert.sameValue(called, 1, "toPrimitive is called - non-NaN number");
called = 0;
obj[Symbol.toPrimitive] = function() {
called += 1;
return "this is not a number";
};
assert.sameValue(isNaN(obj), true, "use returned value - string to NaN");
assert.sameValue(called, 1, "toPrimitive is called - string to NaN");
called = 0;
obj[Symbol.toPrimitive] = function() {
called += 1;
return true;
};
assert.sameValue(isNaN(obj), false, "use returned value - boolean true");
assert.sameValue(called, 1, "toPrimitive is called - boolean true");
called = 0;
obj[Symbol.toPrimitive] = function() {
called += 1;
return false;
};
assert.sameValue(isNaN(obj), false, "use returned value - boolean false");
assert.sameValue(called, 1, "toPrimitive is called - boolean false");
called = 0;
obj[Symbol.toPrimitive] = function() {
called += 1;
return NaN;
};
assert.sameValue(isNaN(obj), true, "use returned value - NaN");
assert.sameValue(called, 1, "toPrimitive is called - NaN");
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