Add tests for well-known Symbol: @@toPrimitive

test/built-ins/Date/prototype/Symbol.toPrimitive/hint-default.js

@@ -0,0 +1,84 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Behavior when `hint` argument is specified as "default"
+info: >
+    1. Let O be the this value.
+    2. If Type(O) is not Object, throw a TypeError exception.
+    3. If hint is the String value "string" or the String value "default", then
+       a. Let tryFirst be "string".
+    4. Else if hint is the String value "number", then
+       a. Let tryFirst be "number".
+    5. Else, throw a TypeError exception.
+    6. Return OrdinaryToPrimitive(O, tryFirst).
+features: [Symbol.toPrimitive]
+---*/
+
+var voAccessCount, voCallCount, tsCallCount;
+var obj;
+
+obj = {
+  get valueOf() {
+    voAccessCount += 1;
+  },
+  toString: function() {
+    tsCallCount += 1;
+    return 'toString test262';
+  }
+};
+
+voAccessCount = 0;
+tsCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'default'),
+  'toString test262'
+);
+assert.sameValue(voAccessCount, 0, '`valueOf` method was not referenced');
+assert.sameValue(tsCallCount, 1, '`toString` method was invoked exactly once');
+
+obj = {
+  valueOf: function() {
+    voCallCount += 1;
+    return 'valueOf test262';
+  },
+  toString: function() {
+    tsCallCount += 1;
+    return {};
+  }
+};
+
+voCallCount = 0;
+tsCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'default'),
+  'valueOf test262',
+  '`valueOf` is used as a fallback when `toString` returns an object'
+);
+assert.sameValue(voCallCount, 1, '`valueOf` method was invoked exactly once');
+assert.sameValue(tsCallCount, 1, '`toString` method was invoked exactly once');
+
+obj = {
+  valueOf: function() {
+    voCallCount += 1;
+    return 'valueOf test262';
+  },
+  toString: null
+};
+
+voCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'default'),
+  'valueOf test262',
+  '`valueOf` is used as a fallback when `toString` is not callable'
+);
+assert.sameValue(voCallCount, 1, '`valueOf` method was invoked exactly once');
+
+obj = {
+  valueOf: null,
+  toString: null
+};
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(obj, 'default');
+});

test/built-ins/Date/prototype/Symbol.toPrimitive/hint-invalid.js

@@ -0,0 +1,51 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Behavior when an invalid `hint` argument is specified
+info: >
+    1. Let O be the this value.
+    2. If Type(O) is not Object, throw a TypeError exception.
+    3. If hint is the String value "string" or the String value "default", then
+       a. Let tryFirst be "string".
+    4. Else if hint is the String value "number", then
+       a. Let tryFirst be "number".
+    5. Else, throw a TypeError exception.
+features: [Symbol.toPrimitive]
+---*/
+
+var d = new Date();
+
+assert.sameValue(typeof d[Symbol.toPrimitive], 'function');
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive]();
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive](undefined);
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive](null);
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive]('');
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive]('String');
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive]('defaultnumber');
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive](new String('number'));
+});
+
+assert.throws(TypeError, function() {
+  d[Symbol.toPrimitive]({ toString: function() { 'number'; } });
+});

test/built-ins/Date/prototype/Symbol.toPrimitive/hint-number.js

@@ -0,0 +1,84 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Behavior when `hint` argument is specified as "number"
+info: >
+    1. Let O be the this value.
+    2. If Type(O) is not Object, throw a TypeError exception.
+    3. If hint is the String value "string" or the String value "default", then
+       a. Let tryFirst be "string".
+    4. Else if hint is the String value "number", then
+       a. Let tryFirst be "number".
+    5. Else, throw a TypeError exception.
+    6. Return OrdinaryToPrimitive(O, tryFirst).
+features: [Symbol.toPrimitive]
+---*/
+
+var voCallCount, tsAccessCount, tsCallCount;
+var obj;
+
+obj = {
+  valueOf: function() {
+    voCallCount += 1;
+    return 'valueOf test262';
+  },
+  get toString() {
+    tsAccessCount += 1;
+  }
+};
+
+voCallCount = 0;
+tsAccessCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'number'),
+  'valueOf test262'
+);
+assert.sameValue(voCallCount, 1, '`valueOf` method was invoked exactly once');
+assert.sameValue(tsAccessCount, 0, '`toString` method was not referenced');
+
+obj = {
+  valueOf: function() {
+    voCallCount += 1;
+    return {};
+  },
+  toString: function() {
+    tsCallCount += 1;
+    return 'toString test262';
+  }
+};
+
+voCallCount = 0;
+tsCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'number'),
+  'toString test262',
+  '`toString` is used as a fallback when `valueOf` returns an object'
+);
+assert.sameValue(voCallCount, 1, '`valueOf` method was invoked exactly once');
+assert.sameValue(tsCallCount, 1, '`toString` method was invoked exactly once');
+
+obj = {
+  valueOf: null,
+  toString: function() {
+    tsCallCount += 1;
+    return 'toString test262';
+  }
+};
+
+tsCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'number'),
+  'toString test262',
+  '`toString` is used as a fallback when `valueOf` is not callable'
+);
+assert.sameValue(tsCallCount, 1, '`toString` method was invoked exactly once');
+
+obj = {
+  valueOf: null,
+  toString: null
+};
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(obj, 'number');
+});

test/built-ins/Date/prototype/Symbol.toPrimitive/hint-string.js

@@ -0,0 +1,84 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Behavior when `hint` argument is specified as "string"
+info: >
+    1. Let O be the this value.
+    2. If Type(O) is not Object, throw a TypeError exception.
+    3. If hint is the String value "string" or the String value "default", then
+       a. Let tryFirst be "string".
+    4. Else if hint is the String value "number", then
+       a. Let tryFirst be "number".
+    5. Else, throw a TypeError exception.
+    6. Return OrdinaryToPrimitive(O, tryFirst).
+features: [Symbol.toPrimitive]
+---*/
+
+var voAccessCount, voCallCount, tsCallCount;
+var obj;
+
+obj = {
+  get valueOf() {
+    voAccessCount += 1;
+  },
+  toString: function() {
+    tsCallCount += 1;
+    return 'toString test262';
+  }
+};
+
+voAccessCount = 0;
+tsCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'string'),
+  'toString test262'
+);
+assert.sameValue(voAccessCount, 0, '`valueOf` method was not referenced');
+assert.sameValue(tsCallCount, 1, '`toString` method was invoked exactly once');
+
+obj = {
+  valueOf: function() {
+    voCallCount += 1;
+    return 'valueOf test262';
+  },
+  toString: function() {
+    tsCallCount += 1;
+    return {};
+  }
+};
+
+voCallCount = 0;
+tsCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'string'),
+  'valueOf test262',
+  '`valueOf` is used as a fallback when `toString` returns an object'
+);
+assert.sameValue(voCallCount, 1, '`valueOf` method was invoked exactly once');
+assert.sameValue(tsCallCount, 1, '`toString` method was invoked exactly once');
+
+obj = {
+  valueOf: function() {
+    voCallCount += 1;
+    return 'valueOf test262';
+  },
+  toString: null
+};
+
+voCallCount = 0;
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].call(obj, 'string'),
+  'valueOf test262',
+  '`valueOf` is used as a fallback when `toString` is not callable'
+);
+assert.sameValue(voCallCount, 1, '`valueOf` method was invoked exactly once');
+
+obj = {
+  valueOf: null,
+  toString: null
+};
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(obj, 'string');
+});

test/built-ins/Date/prototype/Symbol.toPrimitive/length.js

@@ -0,0 +1,27 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Date.prototype[Symbol.toPrimitive] `length` property
+info: >
+    ES6 section 17:
+
+    Every built-in Function object, including constructors, has a length
+    property whose value is an integer. Unless otherwise specified, this value
+    is equal to the largest number of named arguments shown in the subclause
+    headings for the function description, including optional parameters.
+
+    [...]
+
+    Unless otherwise specified, the length property of a built-in Function
+    object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+features: [Symbol.toPrimitive]
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Date.prototype[Symbol.toPrimitive].length, 1);
+
+verifyNotEnumerable(Date.prototype[Symbol.toPrimitive], 'length');
+verifyNotWritable(Date.prototype[Symbol.toPrimitive], 'length');
+verifyConfigurable(Date.prototype[Symbol.toPrimitive], 'length');

test/built-ins/Date/prototype/Symbol.toPrimitive/name.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Date.prototype[Symbol.toPrimitive] `name` property
+info: >
+    The value of the name property of this function is "[Symbol.toPrimitive]".
+
+    ES6 Section 17:
+
+    [...]
+
+    Unless otherwise specified, the name property of a built-in Function
+    object, if it exists, has the attributes { [[Writable]]: false,
+    [[Enumerable]]: false, [[Configurable]]: true }.
+features: [Symbol.toPrimitive]
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Date.prototype[Symbol.toPrimitive].name, '[Symbol.toPrimitive]'
+);
+
+verifyNotEnumerable(Date.prototype[Symbol.toPrimitive], 'name');
+verifyNotWritable(Date.prototype[Symbol.toPrimitive], 'name');
+verifyConfigurable(Date.prototype[Symbol.toPrimitive], 'name');

test/built-ins/Date/prototype/Symbol.toPrimitive/prop-desc.js

@@ -0,0 +1,16 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+es6id: 20.3.4.45
+description: Date.prototype[Symbol.toPrimitive] property descriptor
+info: >
+    This property has the attributes { [[Writable]]: false, [[Enumerable]]:
+    false, [[Configurable]]: true }.
+includes: [propertyHelper.js]
+features: [Symbol.toPrimitive]
+---*/
+
+verifyNotEnumerable(Date.prototype, Symbol.toPrimitive);
+verifyNotWritable(Date.prototype, Symbol.toPrimitive);
+verifyConfigurable(Date.prototype, Symbol.toPrimitive);

test/built-ins/Date/prototype/Symbol.toPrimitive/this-val-non-obj.js

@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 20.3.4.45
+description: Behavior when `this` value is not an Object
+info: >
+    1. Let O be the this value.
+    2. If Type(O) is not Object, throw a TypeError exception.
+features: [Symbol.toPrimitive]
+---*/
+
+assert.sameValue(typeof Date.prototype[Symbol.toPrimitive], 'function');
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(undefined, 'string');
+});
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(null, 'string');
+});
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(86, 'string');
+});
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call('', 'string');
+});
+
+assert.throws(TypeError, function() {
+  Date.prototype[Symbol.toPrimitive].call(true, 'string');
+});

test/built-ins/Symbol/prototype/Symbol.toPrimitive/length.js

@@ -0,0 +1,27 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.3.4
+description: Symbol.prototype[Symbol.toPrimitive] `length` property
+info: >
+    ES6 section 17:
+
+    Every built-in Function object, including constructors, has a length
+    property whose value is an integer. Unless otherwise specified, this value
+    is equal to the largest number of named arguments shown in the subclause
+    headings for the function description, including optional parameters.
+
+    [...]
+
+    Unless otherwise specified, the length property of a built-in Function
+    object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+features: [Symbol.toPrimitive]
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Symbol.prototype[Symbol.toPrimitive].length, 1);
+
+verifyNotEnumerable(Symbol.prototype[Symbol.toPrimitive], 'length');
+verifyNotWritable(Symbol.prototype[Symbol.toPrimitive], 'length');
+verifyConfigurable(Symbol.prototype[Symbol.toPrimitive], 'length');

test/built-ins/Symbol/prototype/Symbol.toPrimitive/name.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.3.4
+description: Symbol.prototype[Symbol.toPrimitive] `name` property
+info: >
+    The value of the name property of this function is "[Symbol.toPrimitive]".
+
+    ES6 Section 17:
+
+    [...]
+
+    Unless otherwise specified, the name property of a built-in Function
+    object, if it exists, has the attributes { [[Writable]]: false,
+    [[Enumerable]]: false, [[Configurable]]: true }.
+features: [Symbol.toPrimitive]
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(
+  Symbol.prototype[Symbol.toPrimitive].name, '[Symbol.toPrimitive]'
+);
+
+verifyNotEnumerable(Symbol.prototype[Symbol.toPrimitive], 'name');
+verifyNotWritable(Symbol.prototype[Symbol.toPrimitive], 'name');
+verifyConfigurable(Symbol.prototype[Symbol.toPrimitive], 'name');

test/built-ins/Symbol/prototype/Symbol.toPrimitive/prop-desc.js

@@ -0,0 +1,16 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+es6id: 19.4.3.4
+description: Symbol.prototype[Symbol.toPrimitive] property descriptor
+info: >
+    This property has the attributes { [[Writable]]: false, [[Enumerable]]:
+    false, [[Configurable]]: true }.
+includes: [propertyHelper.js]
+features: [Symbol.toPrimitive]
+---*/
+
+verifyNotEnumerable(Symbol.prototype, Symbol.toPrimitive);
+verifyNotWritable(Symbol.prototype, Symbol.toPrimitive);
+verifyConfigurable(Symbol.prototype, Symbol.toPrimitive);

test/built-ins/Symbol/prototype/Symbol.toPrimitive/this-val-non-obj.js

@@ -0,0 +1,33 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.3.4
+description: Behavior when `this` value is neither a Symbol nor an Object
+info: >
+    1. Let s be the this value.
+    2. If Type(s) is Symbol, return s.
+    3. If Type(s) is not Object, throw a TypeError exception.
+features: [Symbol.toPrimitive]
+---*/
+
+assert.sameValue(typeof Symbol.prototype[Symbol.toPrimitive], 'function');
+
+assert.throws(TypeError, function() {
+  Symbol.prototype[Symbol.toPrimitive].call(undefined);
+});
+
+assert.throws(TypeError, function() {
+  Symbol.prototype[Symbol.toPrimitive].call(null);
+});
+
+assert.throws(TypeError, function() {
+  Symbol.prototype[Symbol.toPrimitive].call(86);
+});
+
+assert.throws(TypeError, function() {
+  Symbol.prototype[Symbol.toPrimitive].call('');
+});
+
+assert.throws(TypeError, function() {
+  Symbol.prototype[Symbol.toPrimitive].call(true);
+});

test/built-ins/Symbol/prototype/Symbol.toPrimitive/this-val-obj-non-symbol-wrapper.js

@@ -0,0 +1,19 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.3.4
+description: >
+    Behavior when `this` value is an object without a [[SymbolData]] internal
+    slot
+info: >
+    1. Let s be the this value.
+    2. If Type(s) is Symbol, return s.
+    3. If Type(s) is not Object, throw a TypeError exception.
+    4. If s does not have a [[SymbolData]] internal slot, throw a TypeError
+       exception.
+features: [Symbol.toPrimitive]
+---*/
+
+assert.throws(TypeError, function() {
+  Symbol.prototype[Symbol.toPrimitive].call({});
+});

test/built-ins/Symbol/prototype/Symbol.toPrimitive/this-val-obj-symbol-wrapper.js

@@ -0,0 +1,20 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.3.4
+description: >
+    Behavior when `this` value is an object with a [[SymboldData]] internal
+    slot
+info: >
+    1. Let s be the this value.
+    2. If Type(s) is Symbol, return s.
+    3. If Type(s) is not Object, throw a TypeError exception.
+    4. If s does not have a [[SymbolData]] internal slot, throw a TypeError
+       exception.
+    5. Return the value of s’s [[SymbolData]] internal slot.
+features: [Symbol.toPrimitive]
+---*/
+
+assert.sameValue(
+  Object(Symbol.toPrimitive)[Symbol.toPrimitive](), Symbol.toPrimitive
+);

test/built-ins/Symbol/prototype/Symbol.toPrimitive/this-val-symbol.js

@@ -0,0 +1,12 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.3.4
+description: Behavior when `this` value is a Symbol
+info: >
+    1. Let s be the this value.
+    2. If Type(s) is Symbol, return s.
+features: [Symbol.toPrimitive]
+---*/
+
+assert.sameValue(Symbol.toPrimitive[Symbol.toPrimitive](), Symbol.toPrimitive);

test/built-ins/Symbol/toPrimitive/prop-desc.js

@@ -0,0 +1,17 @@
+// Copyright (C) 2015 the V8 project authors. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+es6id: 19.4.2.12
+description: >
+    `Symbol.toPrimitive` property descriptor
+info: >
+    This property has the attributes { [[Writable]]: false, [[Enumerable]]:
+    false, [[Configurable]]: false }.
+includes: [propertyHelper.js]
+features: [Symbol.toPrimitive]
+---*/
+
+assert.sameValue(typeof Symbol.toPrimitive, 'symbol');
+verifyNotEnumerable(Symbol, 'toPrimitive');
+verifyNotWritable(Symbol, 'toPrimitive');
+verifyNotConfigurable(Symbol, 'toPrimitive');

test/language/expressions/equals/coerce-symbol-to-prim-err.js

@@ -0,0 +1,37 @@
+// 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: >
+    Behavior when error thrown by 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] )
+
+    [...]
+    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»).
+       b. ReturnIfAbrupt(result).
+features: [Symbol.toPrimitive]
+---*/
+
+var y = {};
+y[Symbol.toPrimitive] = function() {
+  throw new Test262Error();
+};
+
+assert.throws(Test262Error, function() {
+  0 == y;
+});

test/language/expressions/equals/coerce-symbol-to-prim-invocation.js

@@ -0,0 +1,48 @@
+// 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'
+);

test/language/expressions/equals/coerce-symbol-to-prim-return-obj.js

@@ -0,0 +1,51 @@
+// 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: >
+    Behavior when coercion via `Symbol.toPrimitive` yields an Object
+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] )
+
+    [...]
+    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»).
+       b. ReturnIfAbrupt(result).
+       c. If Type(result) is not Object, return result.
+       d. Throw a TypeError exception.
+features: [Symbol.toPrimitive]
+---*/
+
+var y = {};
+var retVal;
+
+y[Symbol.toPrimitive] = function() {
+  return retVal;
+};
+
+retVal = {};
+assert.throws(TypeError, function() {
+  0 == y;
+});
+
+retVal = new Number();
+assert.throws(TypeError, function() {
+  0 == y;
+});
+
+retVal = new String();
+assert.throws(TypeError, function() {
+  0 == y;
+});

test/language/expressions/equals/coerce-symbol-to-prim-return-prim.js

@@ -0,0 +1,47 @@
+// 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: >
+    Behavior when coercion via `Symbol.toPrimitive` yields a primitive value
+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] )
+
+    [...]
+    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»).
+       b. ReturnIfAbrupt(result).
+       c. If Type(result) is not Object, return result.
+features: [Symbol.toPrimitive]
+---*/
+
+var y = {};
+var retVal;
+
+y[Symbol.toPrimitive] = function() {
+  return retVal;
+};
+
+retVal = 86;
+assert.sameValue(0 == y, false, 'number primitive (not equal)');
+assert.sameValue(86 == y, true, 'number primitive (equal)');
+
+retVal = 'str';
+assert.sameValue(0 == y, false, 'string primitive (not equal)');
+assert.sameValue('str' == y, true, 'sting primitive (equal)');
+
+retVal = Symbol.toPrimitive;
+assert.sameValue(0 == y, false, 'symbol (not equal)');
+assert.sameValue(Symbol.toPrimitive == y, true, 'symbol (equal)');

test/language/expressions/equals/get-symbol-to-prim-err.js

@@ -0,0 +1,34 @@
+// 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: >
+    Behavior when error thrown while accessing `Symbol.toPrimitive` property
+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] )
+
+    [...]
+    4. Let exoticToPrim be GetMethod(input, @@toPrimitive).
+    5. ReturnIfAbrupt(exoticToPrim).
+features: [Symbol.toPrimitive]
+---*/
+
+var y = Object.defineProperty({}, Symbol.toPrimitive, {
+  get: function() {
+    throw new Test262Error();
+  }
+});
+
+assert.throws(Test262Error, function() {
+  0 == y;
+});