gecko-dev/dom/imptests/idlharness.js

/*
Distributed under both the W3C Test Suite License [1] and the W3C
3-clause BSD License [2]. To contribute to a W3C Test Suite, see the
policies and contribution forms [3].

[1] http://www.w3.org/Consortium/Legal/2008/04-testsuite-license
[2] http://www.w3.org/Consortium/Legal/2008/03-bsd-license
[3] http://www.w3.org/2004/10/27-testcases
*/

/*
 * This file automatically generates browser tests for WebIDL interfaces, using
 * the testharness.js framework.  To use, first include the following:
 *
 *   <script src=/resources/testharness.js></script>
 *   <script src=/resources/testharnessreport.js></script>
 *   <script src=/resources/WebIDLParser.js></script>
 *   <script src=/resources/idlharness.js></script>
 *
 * Then you'll need some type of IDLs.  Here's some script that can be run on a
 * spec written in HTML, which will grab all the elements with class="idl",
 * concatenate them, and replace the body so you can copy-paste:
 *
     var s = "";
     [].forEach.call(document.getElementsByClassName("idl"), function(idl) {
       //https://www.w3.org/Bugs/Public/show_bug.cgi?id=14914
       if (!idl.classList.contains("extract"))
       {
         s += idl.textContent + "\n\n";
       }
     });
     document.body.innerHTML = '<pre></pre>';
     document.body.firstChild.textContent = s;
 *
 * (TODO: write this in Python or something so that it can be done from the
 * command line instead.)
 *
 * Once you have that, put it in your script somehow.  The easiest way is to
 * embed it literally in an HTML file with <script type=text/plain> or similar,
 * so that you don't have to do any escaping.  Another possibility is to put it
 * in a separate .idl file that's fetched via XHR or similar.  Sample usage:
 *
 *   var idl_array = new IdlArray();
 *   idl_array.add_untested_idls("interface Node { readonly attribute DOMString nodeName; };");
 *   idl_array.add_idls("interface Document : Node { readonly attribute DOMString URL; };");
 *   idl_array.add_objects({Document: ["document"]});
 *   idl_array.test();
 *
 * This tests that window.Document exists and meets all the requirements of
 * WebIDL.  It also tests that window.document (the result of evaluating the
 * string "document") has URL and nodeName properties that behave as they
 * should, and otherwise meets WebIDL's requirements for an object whose
 * primary interface is Document.  It does not test that window.Node exists,
 * which is what you want if the Node interface is already tested in some other
 * specification's suite and your specification only extends or refers to it.
 * Of course, each IDL string can define many different things, and calls to
 * add_objects() can register many different objects for different interfaces:
 * this is a very simple example.
 *
 * TODO: Write assert_writable, assert_enumerable, assert_configurable and
 * their inverses, and use those instead of just checking
 * getOwnPropertyDescriptor.
 *
 * == Public methods of IdlArray ==
 *
 * IdlArray objects can be obtained with new IdlArray().  Anything not
 * documented in this section should be considered an implementation detail,
 * and outside callers should not use it.
 *
 * add_idls(idl_string):
 *   Parses idl_string (throwing on parse error) and adds the results to the
 *   IdlArray.  All the definitions will be tested when you run test().  If
 *   some of the definitions refer to other definitions, those must be present
 *   too.  For instance, if idl_string says that Document inherits from Node,
 *   the Node interface must also have been provided in some call to add_idls()
 *   or add_untested_idls().
 *
 * add_untested_idls(idl_string):
 *   Like add_idls(), but the definitions will not be tested.  If an untested
 *   interface is added and then extended with a tested partial interface, the
 *   members of the partial interface will still be tested.  Also, all the
 *   members will still be tested for objects added with add_objects(), because
 *   you probably want to test that (for instance) window.document has all the
 *   properties from Node, not just Document, even if the Node interface itself
 *   is tested in a different test suite.
 *
 * add_objects(dict):
 *   dict should be an object whose keys are the names of interfaces or
 *   exceptions, and whose values are arrays of strings.  When an interface or
 *   exception is tested, every string registered for it with add_objects()
 *   will be evaluated, and tests will be run on the result to verify that it
 *   correctly implements that interface or exception.  This is the only way to
 *   test anything about [NoInterfaceObject] interfaces, and there are many
 *   tests that can't be run on any interface without an object to fiddle with.
 *
 *   The interface has to be the *primary* interface of all the objects
 *   provided.  For example, don't pass {Node: ["document"]}, but rather
 *   {Document: ["document"]}.  Assuming the Document interface was declared to
 *   inherit from Node, this will automatically test that document implements
 *   the Node interface too.
 *
 *   Warning: methods will be called on any provided objects, in a manner that
 *   WebIDL requires be safe.  For instance, if a method has mandatory
 *   arguments, the test suite will try calling it with too few arguments to
 *   see if it throws an exception.  If an implementation incorrectly runs the
 *   function instead of throwing, this might have side effects, possibly even
 *   preventing the test suite from running correctly.
 *
 * prevent_multiple_testing(name):
 *   This is a niche method for use in case you're testing many objects that
 *   implement the same interfaces, and don't want to retest the same
 *   interfaces every single time.  For instance, HTML defines many interfaces
 *   that all inherit from HTMLElement, so the HTML test suite has something
 *   like
 *     .add_objects({
 *         HTMLHtmlElement: ['document.documentElement'],
 *         HTMLHeadElement: ['document.head'],
 *         HTMLBodyElement: ['document.body'],
 *         ...
 *     })
 *   and so on for dozens of element types.  This would mean that it would
 *   retest that each and every one of those elements implements HTMLElement,
 *   Element, and Node, which would be thousands of basically redundant tests.
 *   The test suite therefore calls prevent_multiple_testing("HTMLElement").
 *   This means that once one object has been tested to implement HTMLElement
 *   and its ancestors, no other object will be.  Thus in the example code
 *   above, the harness would test that document.documentElement correctly
 *   implements HTMLHtmlElement, HTMLElement, Element, and Node; but
 *   document.head would only be tested for HTMLHeadElement, and so on for
 *   further objects.
 *
 * test():
 *   Run all tests.  This should be called after you've called all other
 *   methods to add IDLs and objects.
 */

/**
 * Notes for people who want to edit this file (not just use it as a library):
 *
 * Most of the interesting stuff happens in the derived classes of IdlObject,
 * especially IdlInterface.  The entry point for all IdlObjects is .test(),
 * which is called by IdlArray.test().  An IdlObject is conceptually just
 * "thing we want to run tests on", and an IdlArray is an array of IdlObjects
 * with some additional data thrown in.
 *
 * The object model is based on what WebIDLParser.js produces, which is in turn
 * based on its pegjs grammar.  If you want to figure out what properties an
 * object will have from WebIDLParser.js, the best way is to look at the
 * grammar:
 *
 *   https://github.com/darobin/webidl.js/blob/master/lib/grammar.peg
 *
 * So for instance:
 *
 *   // interface definition
 *   interface
 *       =   extAttrs:extendedAttributeList? S? "interface" S name:identifier w herit:ifInheritance? w "{" w mem:ifMember* w "}" w ";" w
 *           { return { type: "interface", name: name, inheritance: herit, members: mem, extAttrs: extAttrs }; }
 *
 * This means that an "interface" object will have a .type property equal to
 * the string "interface", a .name property equal to the identifier that the
 * parser found, an .inheritance property equal to either null or the result of
 * the "ifInheritance" production found elsewhere in the grammar, and so on.
 * After each grammatical production is a JavaScript function in curly braces
 * that gets called with suitable arguments and returns some JavaScript value.
 *
 * (Note that the version of WebIDLParser.js we use might sometimes be
 * out-of-date or forked.)
 *
 * The members and methods of the classes defined by this file are all at least
 * briefly documented, hopefully.
 */
"use strict";
(function(){
/// IdlArray ///
// Entry point
window.IdlArray = function()
//@{
{
    /**
     * A map from strings to the corresponding named IdlObject, such as
     * IdlInterface or IdlException.  These are the things that test() will run
     * tests on.
     */
    this.members = {};

    /**
     * A map from strings to arrays of strings.  The keys are interface or
     * exception names, and are expected to also exist as keys in this.members
     * (otherwise they'll be ignored).  This is populated by add_objects() --
     * see documentation at the start of the file.  The actual tests will be
     * run by calling this.members[name].test_object(obj) for each obj in
     * this.objects[name].  obj is a string that will be eval'd to produce a
     * JavaScript value, which is supposed to be an object implementing the
     * given IdlObject (interface, exception, etc.).
     */
    this.objects = {};

    /**
     * When adding multiple collections of IDLs one at a time, an earlier one
     * might contain a partial interface or implements statement that depends
     * on a later one.  Save these up and handle them right before we run
     * tests.
     *
     * .partials is simply an array of objects from WebIDLParser.js'
     * "partialinterface" production.  .implements maps strings to arrays of
     * strings, such that
     *
     *   A implements B;
     *   A implements C;
     *   D implements E;
     *
     * results in { A: ["B", "C"], D: ["E"] }.
     */
    this.partials = [];
    this.implements = {};
}

//@}
IdlArray.prototype.add_idls = function(raw_idls)
//@{
{
    /** Entry point.  See documentation at beginning of file. */
    this.internal_add_idls(WebIDLParser.parse(raw_idls));
};

//@}
IdlArray.prototype.add_untested_idls = function(raw_idls)
//@{
{
    /** Entry point.  See documentation at beginning of file. */
    var parsed_idls = WebIDLParser.parse(raw_idls);
    for (var i = 0; i < parsed_idls.length; i++)
    {
        parsed_idls[i].untested = true;
        if ("members" in parsed_idls[i])
        {
            for (var j = 0; j < parsed_idls[i].members.length; j++)
            {
                parsed_idls[i].members[j].untested = true;
            }
        }
    }
    this.internal_add_idls(parsed_idls);
}

//@}
IdlArray.prototype.internal_add_idls = function(parsed_idls)
//@{
{
    /**
     * Internal helper called by add_idls() and add_untested_idls().
     * parsed_idls is an array of objects that come from WebIDLParser.js's
     * "definitions" production.  The add_untested_idls() entry point
     * additionally sets an .untested property on each object (and its
     * .members) so that they'll be skipped by test() -- they'll only be
     * used for base interfaces of tested interfaces, return types, etc.
     */
    parsed_idls.forEach(function(parsed_idl)
    {
        if (parsed_idl.type == "partialinterface")
        {
            this.partials.push(parsed_idl);
            return;
        }

        if (parsed_idl.type == "implements")
        {
            if (!(parsed_idl.target in this.implements))
            {
                this.implements[parsed_idl.target] = [];
            }
            this.implements[parsed_idl.target].push(parsed_idl.implements);
            return;
        }

        parsed_idl.array = this;
        if (parsed_idl.name in this.members)
        {
            throw "Duplicate identifier " + parsed_idl.name;
        }
        switch(parsed_idl.type)
        {
        case "interface":
            this.members[parsed_idl.name] = new IdlInterface(parsed_idl);
            break;

        case "exception":
            this.members[parsed_idl.name] = new IdlException(parsed_idl);
            break;

        case "dictionary":
            // Nothing to test, but we need the dictionary info around for type
            // checks
            this.members[parsed_idl.name] = new IdlDictionary(parsed_idl);
            break;

        case "typedef":
            // TODO
            break;

        case "enum":
            // TODO
            break;

        default:
            throw parsed_idl.name + ": " + parsed_idl.type + " not yet supported";
        }
    }.bind(this));
}

//@}
IdlArray.prototype.add_objects = function(dict)
//@{
{
    /** Entry point.  See documentation at beginning of file. */
    for (var k in dict)
    {
        if (k in this.objects)
        {
            this.objects[k] = this.objects[k].concat(dict[k]);
        }
        else
        {
            this.objects[k] = dict[k];
        }
    }
}

//@}
IdlArray.prototype.prevent_multiple_testing = function(name)
//@{
{
    /** Entry point.  See documentation at beginning of file. */
    this.members[name].prevent_multiple_testing = true;
}

//@}
IdlArray.prototype.recursively_get_implements = function(interface_name)
//@{
{
    /**
     * Helper function for test().  Returns an array of things that implement
     * interface_name, so if the IDL contains
     *
     *   A implements B;
     *   B implements C;
     *   B implements D;
     *
     * then recursively_get_implements("A") should return ["B", "C", "D"].
     */
    var ret = this.implements[interface_name];
    if (ret === undefined)
    {
        return [];
    }
    for (var i = 0; i < this.implements[interface_name].length; i++)
    {
        ret = ret.concat(this.recursively_get_implements(ret[i]));
        if (ret.indexOf(ret[i]) != ret.lastIndexOf(ret[i]))
        {
            throw "Circular implements statements involving " + ret[i];
        }
    }
    return ret;
}

//@}
IdlArray.prototype.test = function()
//@{
{
    /** Entry point.  See documentation at beginning of file. */

    // First merge in all the partial interfaces and implements statements we
    // encountered.
    this.partials.forEach(function(parsed_idl)
    {
        if (!(parsed_idl.name in this.members)
        || !(this.members[parsed_idl.name] instanceof IdlInterface))
        {
            throw "Partial interface " + parsed_idl.name + " with no original interface";
        }
        if (parsed_idl.extAttrs)
        {
            parsed_idl.extAttrs.forEach(function(extAttr)
            {
                this.members[parsed_idl.name].extAttrs.push(extAttr);
            }.bind(this));
        }
        parsed_idl.members.forEach(function(member)
        {
            this.members[parsed_idl.name].members.push(new IdlInterfaceMember(member));
        }.bind(this));
    }.bind(this));
    this.partials = [];

    for (var lhs in this.implements)
    {
        this.recursively_get_implements(lhs).forEach(function(rhs)
        {
            if (!(lhs in this.members)
            || !(this.members[lhs] instanceof IdlInterface)
            || !(rhs in this.members)
            || !(this.members[rhs] instanceof IdlInterface))
            {
                throw lhs + " implements " + rhs + ", but one is undefined or not an interface";
            }
            this.members[rhs].members.forEach(function(member)
            {
                this.members[lhs].members.push(new IdlInterfaceMember(member));
            }.bind(this));
        }.bind(this));
    }
    this.implements = {};

    // Now run test() on every member, and test_object() for every object.
    for (var name in this.members)
    {
        this.members[name].test();
        if (name in this.objects)
        {
            this.objects[name].forEach(function(str)
            {
                this.members[name].test_object(str);
            }.bind(this));
        }
    }
};

//@}
IdlArray.prototype.assert_type_is = function(value, type)
//@{
{
    /**
     * Helper function that tests that value is an instance of type according
     * to the rules of WebIDL.  value is any JavaScript value, and type is an
     * object produced by WebIDLParser.js' "type" production.  That production
     * is fairly elaborate due to the complexity of WebIDL's types, so it's
     * best to look at the grammar to figure out what properties it might have.
     */
    if (type.idlType == "any")
    {
        // No assertions to make
        return;
    }

    if (type.nullable && value === null)
    {
        // This is fine
        return;
    }

    if (type.array)
    {
        // TODO: not supported yet
        return;
    }

    if (type.sequence)
    {
        assert_true(Array.isArray(value), "is not array");
        if (!value.length)
        {
            // Nothing we can do.
            return;
        }
        this.assert_type_is(value[0], type.idlType.idlType);
        return;
    }

    type = type.idlType;

    switch(type)
    {
        case "void":
            assert_equals(value, undefined);
            return;

        case "boolean":
            assert_equals(typeof value, "boolean");
            return;

        case "byte":
            assert_equals(typeof value, "number");
            assert_equals(value, Math.floor(value), "not an integer");
            assert_true(-128 <= value && value <= 127, "byte " + value + " not in range [-128, 127]");
            return;

        case "octet":
            assert_equals(typeof value, "number");
            assert_equals(value, Math.floor(value), "not an integer");
            assert_true(0 <= value && value <= 255, "octet " + value + " not in range [0, 255]");
            return;

        case "short":
            assert_equals(typeof value, "number");
            assert_equals(value, Math.floor(value), "not an integer");
            assert_true(-32768 <= value && value <= 32767, "short " + value + " not in range [-32768, 32767]");
            return;

        case "unsigned short":
            assert_equals(typeof value, "number");
            assert_equals(value, Math.floor(value), "not an integer");
            assert_true(0 <= value && value <= 65535, "unsigned short " + value + " not in range [0, 65535]");
            return;

        case "long":
            assert_equals(typeof value, "number");
            assert_equals(value, Math.floor(value), "not an integer");
            assert_true(-2147483648 <= value && value <= 2147483647, "long " + value + " not in range [-2147483648, 2147483647]");
            return;

        case "unsigned long":
            assert_equals(typeof value, "number");
            assert_equals(value, Math.floor(value), "not an integer");
            assert_true(0 <= value && value <= 4294967295, "unsigned long " + value + " not in range [0, 4294967295]");
            return;

        case "long long":
            assert_equals(typeof value, "number");
            return;

        case "unsigned long long":
            assert_equals(typeof value, "number");
            assert_true(0 <= value, "unsigned long long is negative");
            return;

        case "float":
        case "double":
            // TODO: distinguish these cases
            assert_equals(typeof value, "number");
            return;

        case "DOMString":
            assert_equals(typeof value, "string");
            return;

        case "object":
            assert_true(typeof value == "object" || typeof value == "function", "wrong type: not object or function");
            return;
    }

    if (!(type in this.members))
    {
        throw "Unrecognized type " + type;
    }

    if (this.members[type] instanceof IdlInterface)
    {
        // We don't want to run the full
        // IdlInterface.prototype.test_instance_of, because that could result
        // in an infinite loop.  TODO: This means we don't have tests for
        // NoInterfaceObject interfaces, and we also can't test objects that
        // come from another window.
        assert_true(typeof value == "object" || typeof value == "function", "wrong type: not object or function");
        if (value instanceof Object
        && !this.members[type].has_extended_attribute("NoInterfaceObject")
        && type in window)
        {
            assert_true(value instanceof window[type], "not instanceof " + type);
        }
    }
    else if (this.members[type] instanceof IdlDictionary)
    {
        // TODO: Test when we actually have something to test this on
    }
    else
    {
        throw "Type " + type + " isn't an interface or dictionary";
    }
};
//@}

/// IdlObject ///
function IdlObject() {}
IdlObject.prototype.test = function()
//@{
{
    /**
     * By default, this does nothing, so no actual tests are run for IdlObjects
     * that don't define any (e.g., IdlDictionary at the time of this writing).
     */
};

//@}
IdlObject.prototype.has_extended_attribute = function(name)
//@{
{
    /**
     * This is only meaningful for things that support extended attributes,
     * such as interfaces, exceptions, and members.
     */
    return this.extAttrs.some(function(o)
    {
        return o.name == name;
    });
};

//@}

/// IdlDictionary ///
// Used for IdlArray.prototype.assert_type_is
function IdlDictionary(obj)
//@{
{
    /**
     * obj is an object produced by the WebIDLParser.js "dictionary"
     * production.
     */

    /** Self-explanatory. */
    this.name = obj.name;

    /** An array of objects produced by the "dictionaryMember" production. */
    this.members = obj.members;

    /**
     * The name (as a string) of the dictionary type we inherit from, or null
     * if there is none.
     */
    if (obj.inheritance.length > 1) {
        throw "Multiple inheritance is no longer supported in WebIDL";
    }
    this.base = obj.inheritance.length ? obj.inheritance[0] : null;
}

//@}
IdlDictionary.prototype = Object.create(IdlObject.prototype);

/// IdlExceptionOrInterface ///
// Code sharing!
function IdlExceptionOrInterface(obj)
//@{
{
    /**
     * obj is an object produced by the WebIDLParser.js "exception" or
     * "interface" production, as appropriate.
     */

    /** Self-explanatory. */
    this.name = obj.name;

    /** A back-reference to our IdlArray. */
    this.array = obj.array;

    /**
     * An indicator of whether we should run tests on the (exception) interface
     * object and (exception) interface prototype object.  Tests on members are
     * controlled by .untested on each member, not this.
     */
    this.untested = obj.untested;

    /** An array of objects produced by the "ExtAttr" production. */
    this.extAttrs = obj.extAttrs;

    /** An array of IdlInterfaceMembers. */
    this.members = obj.members.map(function(m){return new IdlInterfaceMember(m)});

    /**
     * The name (as a string) of the type we inherit from, or null if there is
     * none.
     */
    if (obj.inheritance.length > 1) {
        throw "Multiple inheritance is no longer supported in WebIDL";
    }
    this.base = obj.inheritance.length ? obj.inheritance[0] : null;
}
 
//@}
IdlExceptionOrInterface.prototype = Object.create(IdlObject.prototype);
IdlExceptionOrInterface.prototype.test = function()
//@{
{
    if (this.has_extended_attribute("NoInterfaceObject"))
    {
        // No tests to do without an instance.  TODO: We should still be able
        // to run tests on the prototype object, if we obtain one through some
        // other means.
        return;
    }

    if (!this.untested)
    {
        // First test things to do with the exception/interface object and
        // exception/interface prototype object.
        this.test_self();
    }
    // Then test things to do with its members (constants, fields, attributes,
    // operations, . . .).  These are run even if .untested is true, because
    // members might themselves be marked as .untested.  This might happen to
    // interfaces if the interface itself is untested but a partial interface
    // that extends it is tested -- then the interface itself and its initial
    // members will be marked as untested, but the members added by the partial
    // interface are still tested.
    this.test_members();
}

//@}

/// IdlException ///
function IdlException(obj) { IdlExceptionOrInterface.call(this, obj); }
IdlException.prototype = Object.create(IdlExceptionOrInterface.prototype);
IdlException.prototype.test_self = function()
//@{
{
    test(function()
    {
        // "For every exception that is not declared with the
        // [NoInterfaceObject] extended attribute, a corresponding property
        // must exist on the exception’s relevant namespace object. The name of
        // the property is the identifier of the exception, and its value is an
        // object called the exception interface object, which provides access
        // to any constants that have been associated with the exception. The
        // property has the attributes { [[Writable]]: true, [[Enumerable]]:
        // false, [[Configurable]]: true }."
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));
        var desc = Object.getOwnPropertyDescriptor(window, this.name);
        assert_false("get" in desc, "window's property " + format_value(this.name) + " has getter");
        assert_false("set" in desc, "window's property " + format_value(this.name) + " has setter");
        assert_true(desc.writable, "window's property " + format_value(this.name) + " is not writable");
        assert_false(desc.enumerable, "window's property " + format_value(this.name) + " is enumerable");
        assert_true(desc.configurable, "window's property " + format_value(this.name) + " is not configurable");

        // "The exception interface object for a given exception must be a
        // function object."
        // "If an object is defined to be a function object, then it has
        // characteristics as follows:"
        // "Its [[Prototype]] internal property is the Function prototype
        // object."
        // Note: This doesn't match browsers as of December 2011, see
        // http://www.w3.org/Bugs/Public/show_bug.cgi?id=14813
        assert_equals(Object.getPrototypeOf(window[this.name]), Function.prototype,
                      "prototype of window's property " + format_value(this.name) + " is not Function.prototype");
        // "Its [[Get]] internal property is set as described in ECMA-262
        // section 15.3.5.4."
        // Not much to test for this.
        // "Its [[Construct]] internal property is set as described in ECMA-262
        // section 13.2.2."
        // Tested below.
        // "Its [[HasInstance]] internal property is set as described in
        // ECMA-262 section 15.3.5.3, unless otherwise specified."
        // TODO
        // "Its [[Class]] internal property is “Function”."
        // String() returns something implementation-dependent, because it
        // calls Function#toString.
        assert_class_string(window[this.name], "Function",
                            "class string of " + this.name);

        // TODO: Test 4.9.1.1. Exception interface object [[Call]] method
        // (which does not match browsers:
        // http://www.w3.org/Bugs/Public/show_bug.cgi?id=14885)
    }.bind(this), this.name + " exception: existence and properties of exception interface object");

    test(function()
    {
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));

        // "The exception interface object must also have a property named
        // “prototype” with attributes { [[Writable]]: false, [[Enumerable]]:
        // false, [[Configurable]]: false } whose value is an object called the
        // exception interface prototype object. This object also provides
        // access to the constants that are declared on the exception."
        assert_own_property(window[this.name], "prototype",
                            'exception "' + this.name + '" does not have own property "prototype"');
        var desc = Object.getOwnPropertyDescriptor(window[this.name], "prototype");
        assert_false("get" in desc, this.name + ".prototype has getter");
        assert_false("set" in desc, this.name + ".prototype has setter");
        assert_false(desc.writable, this.name + ".prototype is writable");
        assert_false(desc.enumerable, this.name + ".prototype is enumerable");
        assert_false(desc.configurable, this.name + ".prototype is configurable");

        // "The exception interface prototype object for a given exception must
        // have an internal [[Prototype]] property whose value is as follows:
        //
        // "If the exception is declared to inherit from another exception,
        // then the value of the internal [[Prototype]] property is the
        // exception interface prototype object for the inherited exception.
        // "Otherwise, the exception is not declared to inherit from another
        // exception. The value of the internal [[Prototype]] property is the
        // Error prototype object ([ECMA-262], section 15.11.3.1)."
        //
        // Note: This doesn't match browsers as of December 2011, see
        // https://www.w3.org/Bugs/Public/show_bug.cgi?id=14887.
        var inherit_exception = this.base ? this.base : "Error";
        assert_own_property(window, inherit_exception,
                            'should inherit from ' + inherit_exception + ', but window has no such property');
        assert_own_property(window[inherit_exception], "prototype",
                            'should inherit from ' + inherit_exception + ', but that object has no "prototype" property');
        assert_equals(Object.getPrototypeOf(window[this.name].prototype),
                      window[inherit_exception].prototype,
                      'prototype of ' + this.name + '.prototype is not ' + inherit_exception + '.prototype');

        // "The class string of an exception interface prototype object is the
        // concatenation of the exception’s identifier and the string
        // “Prototype”."
        assert_class_string(window[this.name].prototype, this.name + "Prototype",
                            "class string of " + this.name + ".prototype");
        // TODO: Test String(), based on ES definition of
        // Error.prototype.toString?
    }.bind(this), this.name + " exception: existence and properties of exception interface prototype object");

    test(function()
    {
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));
        assert_own_property(window[this.name], "prototype",
                            'interface "' + this.name + '" does not have own property "prototype"');

        // "There must be a property named “name” on the exception interface
        // prototype object with attributes { [[Writable]]: true,
        // [[Enumerable]]: false, [[Configurable]]: true } and whose value is
        // the identifier of the exception."
        assert_own_property(window[this.name].prototype, "name",
                'prototype object does not have own property "name"');
        var desc = Object.getOwnPropertyDescriptor(window[this.name].prototype, "name");
        assert_false("get" in desc, this.name + ".prototype.name has getter");
        assert_false("set" in desc, this.name + ".prototype.name has setter");
        assert_true(desc.writable, this.name + ".prototype.name is not writable");
        assert_false(desc.enumerable, this.name + ".prototype.name is enumerable");
        assert_true(desc.configurable, this.name + ".prototype.name is not configurable");
        assert_equals(desc.value, this.name, this.name + ".prototype.name has incorrect value");
    }.bind(this), this.name + " exception: existence and properties of exception interface prototype object's \"name\" property");

    test(function()
    {
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));
        assert_own_property(window[this.name], "prototype",
                            'interface "' + this.name + '" does not have own property "prototype"');

        // "If the [NoInterfaceObject] extended attribute was not specified on
        // the exception, then there must also be a property named
        // “constructor” on the exception interface prototype object with
        // attributes { [[Writable]]: true, [[Enumerable]]: false,
        // [[Configurable]]: true } and whose value is a reference to the
        // exception interface object for the exception."
        assert_own_property(window[this.name].prototype, "constructor",
                            this.name + '.prototype does not have own property "constructor"');
        var desc = Object.getOwnPropertyDescriptor(window[this.name].prototype, "constructor");
        assert_false("get" in desc, this.name + ".prototype.constructor has getter");
        assert_false("set" in desc, this.name + ".prototype.constructor has setter");
        assert_true(desc.writable, this.name + ".prototype.constructor is not writable");
        assert_false(desc.enumerable, this.name + ".prototype.constructor is enumerable");
        assert_true(desc.configurable, this.name + ".prototype.constructor in not configurable");
        assert_equals(window[this.name].prototype.constructor, window[this.name],
                      this.name + '.prototype.constructor is not the same object as ' + this.name);
    }.bind(this), this.name + " exception: existence and properties of exception interface prototype object's \"constructor\" property");
}

//@}
IdlException.prototype.test_members = function()
//@{
{
    for (var i = 0; i < this.members.length; i++)
    {
        var member = this.members[i];
        if (member.untested)
        {
            continue;
        }
        if (member.type == "const" && member.name != "prototype")
        {
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));

                // "For each constant defined on the exception, there must be a
                // corresponding property on the exception interface object, if
                // it exists, if the identifier of the constant is not
                // “prototype”."
                assert_own_property(window[this.name], member.name);
                // "The value of the property is the ECMAScript value that is
                // equivalent to the constant’s IDL value, according to the
                // rules in section 4.2 above."
                assert_equals(window[this.name][member.name], eval(member.value),
                              "property has wrong value");
                // "The property has attributes { [[Writable]]: false,
                // [[Enumerable]]: true, [[Configurable]]: false }."
                var desc = Object.getOwnPropertyDescriptor(window[this.name], member.name);
                assert_false("get" in desc, "property has getter");
                assert_false("set" in desc, "property has setter");
                assert_false(desc.writable, "property is writable");
                assert_true(desc.enumerable, "property is not enumerable");
                assert_false(desc.configurable, "property is configurable");
            }.bind(this), this.name + " exception: constant " + member.name + " on exception interface object");
            // "In addition, a property with the same characteristics must
            // exist on the exception interface prototype object."
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));
                assert_own_property(window[this.name], "prototype",
                                    'exception "' + this.name + '" does not have own property "prototype"');

                assert_own_property(window[this.name].prototype, member.name);
                assert_equals(window[this.name].prototype[member.name], eval(member.value),
                              "property has wrong value");
                var desc = Object.getOwnPropertyDescriptor(window[this.name].prototype, member.name);
                assert_false("get" in desc, "property has getter");
                assert_false("set" in desc, "property has setter");
                assert_false(desc.writable, "property is writable");
                assert_true(desc.enumerable, "property is not enumerable");
                assert_false(desc.configurable, "property is configurable");
            }.bind(this), this.name + " exception: constant " + member.name + " on exception interface prototype object");
        }
        else if (member.type == "field")
        {
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));
                assert_own_property(window[this.name], "prototype",
                                    'exception "' + this.name + '" does not have own property "prototype"');

                // "For each exception field, there must be a corresponding
                // property on the exception interface prototype object, whose
                // characteristics are as follows:
                // "The name of the property is the identifier of the exception
                // field."
                assert_own_property(window[this.name].prototype, member.name);
                // "The property has attributes { [[Get]]: G, [[Enumerable]]:
                // true, [[Configurable]]: true }, where G is the exception
                // field getter, defined below."
                var desc = Object.getOwnPropertyDescriptor(window[this.name].prototype, member.name);
                assert_false("value" in desc, "property descriptor has value but is supposed to be accessor");
                assert_false("writable" in desc, 'property descriptor has "writable" field but is supposed to be accessor');
                // TODO: ES5 doesn't seem to say whether desc should have a
                // .set property.
                assert_true(desc.enumerable, "property is not enumerable");
                assert_true(desc.configurable, "property is not configurable");
                // "The exception field getter is a Function object whose
                // behavior when invoked is as follows:"
                assert_equals(typeof desc.get, "function", "typeof getter");
                // "The value of the Function object’s “length” property is the
                // Number value 0."
                // This test is before the TypeError tests so that it's easiest
                // to see that Firefox 11a1 only fails one assert in this test.
                assert_equals(desc.get.length, 0, "getter length");
                // "Let O be the result of calling ToObject on the this value.
                // "If O is not a platform object representing an exception for
                // the exception on which the exception field was declared,
                // then throw a TypeError."
                // TODO: Test on a platform object representing an exception.
                assert_throws(new TypeError(), function()
                {
                    window[this.name].prototype[member.name];
                }.bind(this), "getting property on prototype object must throw TypeError");
                assert_throws(new TypeError(), function()
                {
                    desc.get.call({});
                }.bind(this), "calling getter on wrong object type must throw TypeError");
            }.bind(this), this.name + " exception: field " + member.name + " on exception interface prototype object");
        }
    }
}

//@}
IdlException.prototype.test_object = function(desc)
//@{
{
    var obj, exception = null;
    try
    {
        obj = eval(desc);
    }
    catch(e)
    {
        exception = e;
    }

    test(function()
    {
        assert_equals(exception, null, "Unexpected exception when evaluating object");
        assert_equals(typeof obj, "object", "wrong typeof object");

        // We can't easily test that its prototype is correct if there's no
        // interface object, or the object is from a different global
        // environment (not instanceof Object).  TODO: test in this case that
        // its prototype at least looks correct, even if we can't test that
        // it's actually correct.
        if (!this.has_extended_attribute("NoInterfaceObject")
        && (typeof obj != "object" || obj instanceof Object))
        {
            assert_own_property(window, this.name,
                                "window does not have own property " + format_value(this.name));
            assert_own_property(window[this.name], "prototype",
                                'exception "' + this.name + '" does not have own property "prototype"');

            // "The value of the internal [[Prototype]] property of the
            // exception object must be the exception interface prototype
            // object from the global environment the exception object is
            // associated with."
            assert_equals(Object.getPrototypeOf(obj),
                          window[this.name].prototype,
                          desc + "'s prototype is not " + this.name + ".prototype");
        }

        // "The class string of the exception object must be the identifier of
        // the exception."
        assert_class_string(obj, this.name, "class string of " + desc);
        // Stringifier is not defined for DOMExceptions, because message isn't
        // defined.
    }.bind(this), this.name + " must be represented by " + desc);

    for (var i = 0; i < this.members.length; i++)
    {
        var member = this.members[i];
        test(function()
        {
            assert_equals(exception, null, "Unexpected exception when evaluating object");
            assert_equals(typeof obj, "object", "wrong typeof object");
            assert_inherits(obj, member.name);
            if (member.type == "const")
            {
                assert_equals(obj[member.name], eval(member.value));
            }
            if (member.type == "field")
            {
                this.array.assert_type_is(obj[member.name], member.idlType);
            }
        }.bind(this), this.name + " exception: " + desc + ' must inherit property "' + member.name + '" with the proper type');
    }
}
//@}

/// IdlInterface ///
function IdlInterface(obj) { IdlExceptionOrInterface.call(this, obj); }
IdlInterface.prototype = Object.create(IdlExceptionOrInterface.prototype);
IdlInterface.prototype.test_self = function()
//@{
{
    test(function()
    {
        // "For every interface that is not declared with the
        // [NoInterfaceObject] extended attribute, a corresponding property
        // must exist on the interface’s relevant namespace object. The name of
        // the property is the identifier of the interface, and its value is an
        // object called the interface object. The property has the attributes
        // { [[Writable]]: true, [[Enumerable]]: false, [[Configurable]]: true
        // }."
        // TODO: Should we test here that the property is actually writable
        // etc., or trust getOwnPropertyDescriptor?
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));
        var desc = Object.getOwnPropertyDescriptor(window, this.name);
        assert_false("get" in desc, "window's property " + format_value(this.name) + " has getter");
        assert_false("set" in desc, "window's property " + format_value(this.name) + " has setter");
        assert_true(desc.writable, "window's property " + format_value(this.name) + " is not writable");
        assert_false(desc.enumerable, "window's property " + format_value(this.name) + " is enumerable");
        assert_true(desc.configurable, "window's property " + format_value(this.name) + " is not configurable");

        // "Interface objects are always function objects."
        // "If an object is defined to be a function object, then it has
        // characteristics as follows:"
        // "Its [[Prototype]] internal property is the Function prototype
        // object."
        // Note: This doesn't match browsers as of December 2011, see
        // http://www.w3.org/Bugs/Public/show_bug.cgi?id=14813
        assert_equals(Object.getPrototypeOf(window[this.name]), Function.prototype,
                      "prototype of window's property " + format_value(this.name) + " is not Function.prototype");
        // "Its [[Get]] internal property is set as described in ECMA-262
        // section 15.3.5.4."
        // Not much to test for this.
        // "Its [[Construct]] internal property is set as described in ECMA-262
        // section 13.2.2."
        // Tested below if no constructor is defined.  TODO: test constructors
        // if defined.
        // "Its [[HasInstance]] internal property is set as described in
        // ECMA-262 section 15.3.5.3, unless otherwise specified."
        // TODO
        // "Its [[Class]] internal property is “Function”."
        // String() returns something implementation-dependent, because it calls
        // Function#toString.
        assert_class_string(window[this.name], "Function", "class string of " + this.name);

        if (!this.has_extended_attribute("Constructor"))
        {
            // "The internal [[Call]] method of the interface object behaves as
            // follows . . .
            //
            // "If I was not declared with a [Constructor] extended attribute,
            // then throw a TypeError."
            assert_throws(new TypeError(), function()
            {
                window[this.name]();
            }.bind(this), "interface object didn't throw TypeError when called as a function");
            assert_throws(new TypeError(), function()
            {
                new window[this.name]();
            }.bind(this), "interface object didn't throw TypeError when called as a constructor");
        }
    }.bind(this), this.name + " interface: existence and properties of interface object");

    if (this.has_extended_attribute("Constructor"))
    {
        test(function()
        {
            assert_own_property(window, this.name,
                                "window does not have own property " + format_value(this.name));

            // "Interface objects for interfaces declared with a [Constructor]
            // extended attribute must have a property named “length” with
            // attributes { [[Writable]]: false, [[Enumerable]]: false,
            // [[Configurable]]: false } whose value is a Number determined as
            // follows: . . .
            // "Return the length of the shortest argument list of the entries
            // in S."
            // TODO: Variadic constructors.  Should generalize this so that it
            // works for testing operation length too (currently we just don't
            // support multiple operations with the same identifier).
            var expected_length = this.extAttrs
                .filter(function(attr) { return attr.name == "Constructor" })
                .map(function(attr) {
                    return attr.arguments ? attr.arguments.filter(
                        function(arg) {
                            return !arg.optional;
                        }).length : 0
                })
                .reduce(function(m, n) { return Math.min(m, n) });
            assert_own_property(window[this.name], "length");
            assert_equals(window[this.name].length, expected_length, "wrong value for " + this.name + ".length");
            var desc = Object.getOwnPropertyDescriptor(window[this.name], "length");
            assert_false("get" in desc, this.name + ".length has getter");
            assert_false("set" in desc, this.name + ".length has setter");
            assert_false(desc.writable, this.name + ".length is writable");
            assert_false(desc.enumerable, this.name + ".length is enumerable");
            assert_false(desc.configurable, this.name + ".length is configurable");
        }.bind(this), this.name + " interface constructor");
    }

    // TODO: Test named constructors if I find any interfaces that have them.

    test(function()
    {
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));

        // "The interface object must also have a property named “prototype”
        // with attributes { [[Writable]]: false, [[Enumerable]]: false,
        // [[Configurable]]: false } whose value is an object called the
        // interface prototype object. This object has properties that
        // correspond to the attributes and operations defined on the
        // interface, and is described in more detail in section 4.5.3 below."
        assert_own_property(window[this.name], "prototype",
                            'interface "' + this.name + '" does not have own property "prototype"');
        var desc = Object.getOwnPropertyDescriptor(window[this.name], "prototype");
        assert_false("get" in desc, this.name + ".prototype has getter");
        assert_false("set" in desc, this.name + ".prototype has setter");
        assert_false(desc.writable, this.name + ".prototype is writable");
        assert_false(desc.enumerable, this.name + ".prototype is enumerable");
        assert_false(desc.configurable, this.name + ".prototype is configurable");

        // Next, test that the [[Prototype]] of the interface prototype object
        // is correct. (This is made somewhat difficult by the existence of
        // [NoInterfaceObject].)
        // TODO: Aryeh thinks there's at least other place in this file where
        //       we try to figure out if an interface prototype object is
        //       correct. Consolidate that code.

        // "The interface prototype object for a given interface A must have an
        // internal [[Prototype]] property whose value is as follows:
        // "If A is not declared to inherit from another interface, then the
        // value of the internal [[Prototype]] property of A is the Array
        // prototype object ([ECMA-262], section 15.4.4) if the interface was
        // declared with ArrayClass, or the Object prototype object otherwise
        // ([ECMA-262], section 15.2.4).
        // "Otherwise, A does inherit from another interface. The value of the
        // internal [[Prototype]] property of A is the interface prototype
        // object for the inherited interface."
        var inherit_interface, inherit_interface_has_interface_object;
        if (this.base) {
            inherit_interface = this.base;
            inherit_interface_has_interface_object =
                !this.array
                     .members[inherit_interface]
                     .has_extended_attribute("NoInterfaceObject");
        } else if (this.has_extended_attribute('ArrayClass')) {
            inherit_interface = 'Array';
            inherit_interface_has_interface_object = true;
        } else {
            inherit_interface = 'Object';
            inherit_interface_has_interface_object = true;
        }
        if (inherit_interface_has_interface_object) {
            assert_own_property(window, inherit_interface,
                                'should inherit from ' + inherit_interface + ', but window has no such property');
            assert_own_property(window[inherit_interface], 'prototype',
                                'should inherit from ' + inherit_interface + ', but that object has no "prototype" property');
            assert_equals(Object.getPrototypeOf(window[this.name].prototype),
                          window[inherit_interface].prototype,
                          'prototype of ' + this.name + '.prototype is not ' + inherit_interface + '.prototype');
        } else {
            // We can't test that we get the correct object, because this is the
            // only way to get our hands on it. We only test that its class
            // string, at least, is correct.
            assert_class_string(Object.getPrototypeOf(window[this.name].prototype),
                                inherit_interface + 'Prototype',
                                'Class name for prototype of ' + this.name +
                                '.prototype is not "' + inherit_interface + 'Prototype"');
        }

        // "The class string of an interface prototype object is the
        // concatenation of the interface’s identifier and the string
        // “Prototype”."
        assert_class_string(window[this.name].prototype, this.name + "Prototype",
                            "class string of " + this.name + ".prototype");
        // String() should end up calling {}.toString if nothing defines a
        // stringifier.
        if (!this.has_stringifier()) {
            assert_equals(String(window[this.name].prototype), "[object " + this.name + "Prototype]",
                    "String(" + this.name + ".prototype)");
        }
    }.bind(this), this.name + " interface: existence and properties of interface prototype object");

    test(function()
    {
        assert_own_property(window, this.name,
                            "window does not have own property " + format_value(this.name));
        assert_own_property(window[this.name], "prototype",
                            'interface "' + this.name + '" does not have own property "prototype"');

        // "If the [NoInterfaceObject] extended attribute was not specified on
        // the interface, then the interface prototype object must also have a
        // property named “constructor” with attributes { [[Writable]]: true,
        // [[Enumerable]]: false, [[Configurable]]: true } whose value is a
        // reference to the interface object for the interface."
        assert_own_property(window[this.name].prototype, "constructor",
                            this.name + '.prototype does not have own property "constructor"');
        var desc = Object.getOwnPropertyDescriptor(window[this.name].prototype, "constructor");
        assert_false("get" in desc, this.name + ".prototype.constructor has getter");
        assert_false("set" in desc, this.name + ".prototype.constructor has setter");
        assert_true(desc.writable, this.name + ".prototype.constructor is not writable");
        assert_false(desc.enumerable, this.name + ".prototype.constructor is enumerable");
        assert_true(desc.configurable, this.name + ".prototype.constructor in not configurable");
        assert_equals(window[this.name].prototype.constructor, window[this.name],
                      this.name + '.prototype.constructor is not the same object as ' + this.name);
    }.bind(this), this.name + ' interface: existence and properties of interface prototype object\'s "constructor" property');
}

//@}
IdlInterface.prototype.test_members = function()
//@{
{
    for (var i = 0; i < this.members.length; i++)
    {
        var member = this.members[i];
        if (member.untested)
        {
            continue;
        }
        if (member.type == "const")
        {
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));

                // "For each constant defined on an interface A, there must be
                // a corresponding property on the interface object, if it
                // exists."
                assert_own_property(window[this.name], member.name);
                // "The value of the property is that which is obtained by
                // converting the constant’s IDL value to an ECMAScript
                // value."
                assert_equals(window[this.name][member.name], eval(member.value),
                              "property has wrong value");
                // "The property has attributes { [[Writable]]: false,
                // [[Enumerable]]: true, [[Configurable]]: false }."
                var desc = Object.getOwnPropertyDescriptor(window[this.name], member.name);
                assert_false("get" in desc, "property has getter");
                assert_false("set" in desc, "property has setter");
                assert_false(desc.writable, "property is writable");
                assert_true(desc.enumerable, "property is not enumerable");
                assert_false(desc.configurable, "property is configurable");
            }.bind(this), this.name + " interface: constant " + member.name + " on interface object");
            // "In addition, a property with the same characteristics must
            // exist on the interface prototype object."
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));
                assert_own_property(window[this.name], "prototype",
                                    'interface "' + this.name + '" does not have own property "prototype"');

                assert_own_property(window[this.name].prototype, member.name);
                assert_equals(window[this.name].prototype[member.name], eval(member.value),
                              "property has wrong value");
                var desc = Object.getOwnPropertyDescriptor(window[this.name], member.name);
                assert_false("get" in desc, "property has getter");
                assert_false("set" in desc, "property has setter");
                assert_false(desc.writable, "property is writable");
                assert_true(desc.enumerable, "property is not enumerable");
                assert_false(desc.configurable, "property is configurable");
            }.bind(this), this.name + " interface: constant " + member.name + " on interface prototype object");
        }
        else if (member.type == "attribute")
        {
            if (member.has_extended_attribute("Unforgeable"))
            {
                // We do the checks in test_interface_of instead
                continue;
            }
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));
                assert_own_property(window[this.name], "prototype",
                                    'interface "' + this.name + '" does not have own property "prototype"');

                // TODO: Needs to test for LenientThis.
                assert_throws(new TypeError(), function() {
                    window[this.name].prototype[member.name];
                }.bind(this), "getting property on prototype object must throw TypeError");

                do_interface_attribute_asserts(window[this.name].prototype, member);
            }.bind(this), this.name + " interface: attribute " + member.name);
        }
        else if (member.type == "operation")
        {
            // TODO: Need to correctly handle multiple operations with the same
            // identifier.
            if (!member.name)
            {
                // Unnamed getter or such
                continue;
            }
            test(function()
            {
                assert_own_property(window, this.name,
                                    "window does not have own property " + format_value(this.name));
                assert_own_property(window[this.name], "prototype",
                                    'interface "' + this.name + '" does not have own property "prototype"');

                // "For each unique identifier of an operation defined on the
                // interface, there must be a corresponding property on the
                // interface prototype object (if it is a regular operation) or
                // the interface object (if it is a static operation), unless
                // the effective overload set for that identifier and operation
                // and with an argument count of 0 (for the ECMAScript language
                // binding) has no entries."
                //
                // TODO: The library doesn't seem to support static operations.
                assert_own_property(window[this.name].prototype, member.name,
                    "interface prototype object missing non-static operation");

                var desc = Object.getOwnPropertyDescriptor(window[this.name].prototype, member.name);
                // "The property has attributes { [[Writable]]: true,
                // [[Enumerable]]: true, [[Configurable]]: true }."
                assert_false("get" in desc, "property has getter");
                assert_false("set" in desc, "property has setter");
                assert_true(desc.writable, "property is not writable");
                assert_true(desc.enumerable, "property is not enumerable");
                assert_true(desc.configurable, "property is not configurable");
                // "The value of the property is a Function object whose
                // behavior is as follows . . ."
                assert_equals(typeof window[this.name].prototype[member.name], "function",
                              "property must be a function");
                // "The value of the Function object’s “length” property is
                // a Number determined as follows:
                // ". . .
                // "Return the length of the shortest argument list of the
                // entries in S."
                //
                // TODO: Doesn't handle overloading or variadic arguments.
                assert_equals(window[this.name].prototype[member.name].length,
                    member.arguments.filter(function(arg) {
                        return !arg.optional;
                    }).length,
                    "property has wrong .length");

                // Make some suitable arguments
                var args = member.arguments.map(function(arg) {
                    return create_suitable_object(arg.type);
                });

                // "Let O be a value determined as follows:
                // ". . .
                // "Otherwise, throw a TypeError."
                // This should be hit if the operation is not static, there is
                // no [ImplicitThis] attribute, and the this value is null.
                //
                // TODO: We currently ignore the static and [ImplicitThis]
                // cases.
                assert_throws(new TypeError(), function() {
                    window[this.name].prototype[member.name].apply(null, args);
                }, "calling operation with this = null didn't throw TypeError");

                // ". . . If O is not null and is also not a platform object
                // that implements interface I, throw a TypeError."
                //
                // TODO: Test a platform object that implements some other
                // interface.  (Have to be sure to get inheritance right.)
                assert_throws(new TypeError(), function() {
                    window[this.name].prototype[member.name].apply({}, args);
                }, "calling operation with this = {} didn't throw TypeError");
            }.bind(this), this.name + " interface: operation " + member.name +
            "(" + member.arguments.map(function(m) { return m.type.idlType; }) +
            ")");
        }
        // TODO: check more member types, like stringifier
    }
}

//@}
IdlInterface.prototype.test_object = function(desc)
//@{
{
    var obj, exception = null;
    try
    {
        obj = eval(desc);
    }
    catch(e)
    {
        exception = e;
    }

    // TODO: WebIDLParser doesn't currently support named legacycallers, so I'm
    // not sure what those would look like in the AST
    var expected_typeof = this.members.some(function(member)
    {
        return member.legacycaller
            || ("idlType" in member && member.idlType.legacycaller)
            || ("idlType" in member && typeof member.idlType == "object"
            && "idlType" in member.idlType && member.idlType.idlType == "legacycaller");
    }) ? "function" : "object";

    this.test_primary_interface_of(desc, obj, exception, expected_typeof);
    var current_interface = this;
    while (current_interface)
    {
        if (!(current_interface.name in this.array.members))
        {
            throw "Interface " + current_interface.name + " not found (inherited by " + this.name + ")";
        }
        if (current_interface.prevent_multiple_testing && current_interface.already_tested)
        {
            return;
        }
        current_interface.test_interface_of(desc, obj, exception, expected_typeof);
        current_interface = this.array.members[current_interface.base];
    }
}

//@}
IdlInterface.prototype.test_primary_interface_of = function(desc, obj, exception, expected_typeof)
//@{
{
    // We can't easily test that its prototype is correct if there's no
    // interface object, or the object is from a different global environment
    // (not instanceof Object).  TODO: test in this case that its prototype at
    // least looks correct, even if we can't test that it's actually correct.
    if (!this.has_extended_attribute("NoInterfaceObject")
    && (typeof obj != expected_typeof || obj instanceof Object))
    {
        test(function()
        {
            assert_equals(exception, null, "Unexpected exception when evaluating object");
            assert_equals(typeof obj, expected_typeof, "wrong typeof object");
            assert_own_property(window, this.name,
                                "window does not have own property " + format_value(this.name));
            assert_own_property(window[this.name], "prototype",
                                'interface "' + this.name + '" does not have own property "prototype"');

            // "The value of the internal [[Prototype]] property of the
            // platform object is the interface prototype object of the primary
            // interface from the platform object’s associated global
            // environment."
            assert_equals(Object.getPrototypeOf(obj),
                          window[this.name].prototype,
                          desc + "'s prototype is not " + this.name + ".prototype");
        }.bind(this), this.name + " must be primary interface of " + desc);
    }

    // "The class string of a platform object that implements one or more
    // interfaces must be the identifier of the primary interface of the
    // platform object."
    test(function()
    {
        assert_equals(exception, null, "Unexpected exception when evaluating object");
        assert_equals(typeof obj, expected_typeof, "wrong typeof object");
        assert_class_string(obj, this.name, "class string of " + desc);
        if (!this.has_stringifier())
        {
            assert_equals(String(obj), "[object " + this.name + "]", "String(" + desc + ")");
        }
    }.bind(this), "Stringification of " + desc);
}

//@}
IdlInterface.prototype.test_interface_of = function(desc, obj, exception, expected_typeof)
//@{
{
    // TODO: Indexed and named properties, more checks on interface members
    this.already_tested = true;

    for (var i = 0; i < this.members.length; i++)
    {
        var member = this.members[i];
        if (member.has_extended_attribute("Unforgeable"))
        {
            test(function()
            {
                assert_equals(exception, null, "Unexpected exception when evaluating object");
                assert_equals(typeof obj, expected_typeof, "wrong typeof object");
                do_interface_attribute_asserts(obj, member);
            }.bind(this), this.name + " interface: " + desc + ' must have own property "' + member.name + '"');
        }
        else if ((member.type == "const"
        || member.type == "attribute"
        || member.type == "operation")
        && member.name)
        {
            test(function()
            {
                assert_equals(exception, null, "Unexpected exception when evaluating object");
                assert_equals(typeof obj, expected_typeof, "wrong typeof object");
                assert_inherits(obj, member.name);
                if (member.type == "const")
                {
                    assert_equals(obj[member.name], eval(member.value));
                }
                if (member.type == "attribute")
                {
                    // Attributes are accessor properties, so they might
                    // legitimately throw an exception rather than returning
                    // anything.
                    var property, thrown = false;
                    try
                    {
                        property = obj[member.name];
                    }
                    catch (e)
                    {
                        thrown = true;
                    }
                    if (!thrown)
                    {
                        this.array.assert_type_is(property, member.idlType);
                    }
                }
                if (member.type == "operation")
                {
                    assert_equals(typeof obj[member.name], "function");
                }
            }.bind(this), this.name + " interface: " + desc + ' must inherit property "' + member.name + '" with the proper type (' + i + ')');
        }
        // TODO: This is wrong if there are multiple operations with the same
        // identifier.
        // TODO: Test passing arguments of the wrong type.
        if (member.type == "operation" && member.name && member.arguments.length)
        {
            test(function()
            {
                assert_equals(exception, null, "Unexpected exception when evaluating object");
                assert_equals(typeof obj, expected_typeof, "wrong typeof object");
                assert_inherits(obj, member.name);
                var args = [];
                for (var i = 0; i < member.arguments.length; i++)
                {
                    if (member.arguments[i].optional)
                    {
                        break;
                    }
                    assert_throws(new TypeError(), function()
                    {
                        obj[member.name].apply(obj, args);
                    }.bind(this), "Called with " + i + " arguments");

                    args.push(create_suitable_object(member.arguments[i].type));
                }
            }.bind(this), this.name + " interface: calling " + member.name +
            "(" + member.arguments.map(function(m) { return m.type.idlType; }) +
            ") on " + desc + " with too few arguments must throw TypeError");
        }
    }
}

//@}
IdlInterface.prototype.has_stringifier = function()
//@{
{
    if (this.members.some(function(member) { return member.stringifier })) {
        return true;
    }
    if (this.base &&
        this.array.members[this.base].has_stringifier()) {
        return true;
    }
    return false;
}

//@}
function do_interface_attribute_asserts(obj, member)
//@{
{
    // "For each attribute defined on the interface, there must exist a
    // corresponding property. If the attribute was declared with the
    // [Unforgeable] extended attribute, then the property exists on every
    // object that implements the interface.  Otherwise, it exists on the
    // interface’s interface prototype object."
    //
    // This is called by test_self() with the prototype as obj, and by
    // test_interface_of() with the object as obj.
    assert_own_property(obj, member.name);

    // "The property has attributes { [[Get]]: G, [[Set]]: S, [[Enumerable]]:
    // true, [[Configurable]]: configurable }, where:
    // "configurable is false if the attribute was declared with the
    // [Unforgeable] extended attribute and true otherwise;
    // "G is the attribute getter, defined below; and
    // "S is the attribute setter, also defined below."
    var desc = Object.getOwnPropertyDescriptor(obj, member.name);
    assert_false("value" in desc, 'property descriptor has value but is supposed to be accessor');
    assert_false("writable" in desc, 'property descriptor has "writable" field but is supposed to be accessor');
    assert_true(desc.enumerable, "property is not enumerable");
    if (member.has_extended_attribute("Unforgeable"))
    {
        assert_false(desc.configurable, "[Unforgeable] property must not be configurable");
    }
    else
    {
        assert_true(desc.configurable, "property must be configurable");
    }

    // "The attribute getter is a Function object whose behavior when invoked
    // is as follows:
    // "...
    // "The value of the Function object’s “length” property is the Number
    // value 0."
    assert_equals(typeof desc.get, "function", "getter must be Function");
    assert_equals(desc.get.length, 0, "getter length must be 0");
    // TODO: Account for LenientThis
    assert_throws(new TypeError(), function()
    {
        desc.get.call({});
    }.bind(this), "calling getter on wrong object type must throw TypeError");

    // TODO: Test calling setter on the interface prototype (should throw
    // TypeError in most cases).
    //
    // "The attribute setter is undefined if the attribute is declared readonly
    // and has neither a [PutForwards] nor a [Replaceable] extended attribute
    // declared on it.  Otherwise, it is a Function object whose behavior when
    // invoked is as follows:
    // "...
    // "The value of the Function object’s “length” property is the Number
    // value 1."
    if (member.readonly
    && !member.has_extended_attribute("PutForwards")
    && !member.has_extended_attribute("Replaceable"))
    {
        assert_equals(desc.set, undefined, "setter must be undefined for readonly attributes");
    }
    else
    {
        assert_equals(typeof desc.set, "function", "setter must be function for PutForwards, Replaceable, or non-readonly attributes");
        assert_equals(desc.set.length, 1, "setter length must be 1");
    }
}
//@}

/// IdlInterfaceMember ///
function IdlInterfaceMember(obj)
//@{
{
    /**
     * obj is an object produced by the WebIDLParser.js "ifMember" production.
     * We just forward all properties to this object without modification,
     * except for special extAttrs handling.
     */
    for (var k in obj)
    {
        this[k] = obj[k];
    }
    if (!("extAttrs" in this))
    {
        this.extAttrs = [];
    }
}

//@}
IdlInterfaceMember.prototype = Object.create(IdlObject.prototype);

/// Internal helper functions ///
function create_suitable_object(type)
//@{
{
    /**
     * type is an object produced by the WebIDLParser.js "type" production.  We
     * return a JavaScript value that matches the type, if we can figure out
     * how.
     */
    if (type.nullable)
    {
        return null;
    }
    switch (type.idlType)
    {
        case "any":
        case "boolean":
            return true;

        case "byte": case "octet": case "short": case "unsigned short":
        case "long": case "unsigned long": case "long long":
        case "unsigned long long": case "float": case "double":
            return 7;

        case "DOMString":
            return "foo";

        case "object":
            return {a: "b"};

        case "Node":
            return document.createTextNode("abc");
    }
    return null;
}
//@}
})();
// vim: set expandtab shiftwidth=4 tabstop=4 foldmarker=@{,@} foldmethod=marker: