diff --git a/test/language/subclassing/Function/instance-length.js b/test/language/subclassing/Function/instance-length.js new file mode 100644 index 0000000000..5cd0e35905 --- /dev/null +++ b/test/language/subclassing/Function/instance-length.js @@ -0,0 +1,27 @@ +// Copyright (C) 2016 the V8 project authors. All rights reserved. +// This code is governed by the BSD license found in the LICENSE file. +/*--- +es6id: 19.2.4.1 +description: Subclassed Function instances has length and name properties +info: > + 19.2.4.1 length + + The value of the length property is an integer that indicates the typical + number of arguments expected by the function. However, the language permits + the function to be invoked with some other number of arguments. The behaviour + of a function when invoked on a number of arguments other than the number + specified by its length property depends on the function. This property has + the attributes { [[Writable]]: false, [[Enumerable]]: false, + [[Configurable]]: true }. +includes: [propertyHelper.js] +---*/ + +class Fn extends Function {} + +var fn = new Fn('a', 'b', 'return a + b'); + +assert.sameValue(fn.length, 2); + +verifyNotEnumerable(fn, 'length'); +verifyNotWritable(fn, 'length'); +verifyConfigurable(fn, 'length'); diff --git a/test/language/subclassing/Function/instance-name.js b/test/language/subclassing/Function/instance-name.js new file mode 100644 index 0000000000..fd4fca7c63 --- /dev/null +++ b/test/language/subclassing/Function/instance-name.js @@ -0,0 +1,39 @@ +// Copyright (C) 2016 the V8 project authors. All rights reserved. +// This code is governed by the BSD license found in the LICENSE file. +/*--- +es6id: 19.2.4.2 +description: Subclassed Function instances has length and name properties +info: > + 19.2.4.2 name + + The value of the name property is an String that is descriptive of the + function. The name has no semantic significance but is typically a variable or + property name that is used to refer to the function at its point of definition + in ECMAScript code. This property has the attributes { [[Writable]]: false, + [[Enumerable]]: false, [[Configurable]]: true }. + + Anonymous functions objects that do not have a contextual name associated with + them by this specification do not have a name own property but inherit the + name property of %FunctionPrototype%. + + 19.2.1.1.1 RuntimeSemantics: CreateDynamicFunction(constructor, newTarget, + kind, args) + + ... + 29. Perform SetFunctionName(F, "anonymous"). + ... +includes: [propertyHelper.js] +---*/ + +class Fn extends Function {} + +var fn = new Fn('a', 'b', 'return a + b'); + +assert.sameValue( + fn.name, 'anonymous', + 'Dynamic Functions are called anonymous' +); + +verifyNotEnumerable(fn, 'name'); +verifyNotWritable(fn, 'name'); +verifyConfigurable(fn, 'name'); diff --git a/test/language/subclassing/Function/regular-subclassing.js b/test/language/subclassing/Function/regular-subclassing.js new file mode 100644 index 0000000000..4791d4907c --- /dev/null +++ b/test/language/subclassing/Function/regular-subclassing.js @@ -0,0 +1,20 @@ +// Copyright (C) 2016 the V8 project authors. All rights reserved. +// This code is governed by the BSD license found in the LICENSE file. +/*--- +es6id: 19.2.1 +description: Subclassing Function +info: > + 19.2.1 The Function Constructor + + ... + + The Function constructor is designed to be subclassable. It may be used as the + value of an extends clause of a class definition. + ... +---*/ + +class Fn extends Function {} + +var fn = new Fn('a', 'return a * 2'); + +assert.sameValue(fn(42), 84); diff --git a/test/language/subclassing/Function/super-must-be-called.js b/test/language/subclassing/Function/super-must-be-called.js new file mode 100644 index 0000000000..f86ea41447 --- /dev/null +++ b/test/language/subclassing/Function/super-must-be-called.js @@ -0,0 +1,35 @@ +// Copyright (C) 2016 the V8 project authors. All rights reserved. +// This code is governed by the BSD license found in the LICENSE file. +/*--- +es6id: 19.2.1 +description: > + super must be called to initialize Function internal slots +info: > + 19.2.1 The Function Constructor + + ... + + The Function constructor is designed to be subclassable. It may be used as the + value of an extends clause of a class definition. Subclass constructors that + intend to inherit the specified Function behaviour must include a super call + to the Function constructor to create and initialize a subclass instances with + the internal slots necessary for built-in function behaviour. + ... +---*/ + +class Fn extends Function { + constructor() {} +} + +assert.throws(ReferenceError, function() { + new Fn(); +}); + +class Fn2 extends Function { + constructor() { + super(); + } +} + +var fn = new Fn2(); +assert(fn instanceof Function);