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// Copyright (C) 2015 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es6id: 12.10.3
description: Invocation of `Symbol.toPrimitive` method during coercion
info: |
[...]
7. Return the result of performing Abstract Equality Comparison rval ==
lval.
ES6 Section 7.2.12 Abstract Equality Comparison
[...]
10. If Type(x) is either String, Number, or Symbol and Type(y) is Object,
then return the result of the comparison x == ToPrimitive(y).
ES6 Section 7.1.1 ToPrimitive ( input [, PreferredType] )
1. If PreferredType was not passed, let hint be "default".
[...]
4. Let exoticToPrim be GetMethod(input, @@toPrimitive).
5. ReturnIfAbrupt(exoticToPrim).
6. If exoticToPrim is not undefined, then
a. Let result be Call(exoticToPrim, input, «hint»).
[...]
features: [Symbol.toPrimitive]
---*/
var y = {};
var callCount = 0;
var thisVal, args;
y[Symbol.toPrimitive] = function() {
callCount += 1;
thisVal = this;
args = arguments;
};
0 == y;
assert.sameValue(callCount, 1, 'method invoked exactly once');
assert.sameValue(thisVal, y, '`this` value is the object being compared');
assert.sameValue(args.length, 1, 'method invoked with exactly one argument');
assert.sameValue(
args[0],
'default',
'method invoked with the string "default" as the first argument'
);
reportCompare(0, 0);