/// <summary>
/// https://tc39.es/ecma262/#sec-runtime-semantics-instantiatefunctionobject
/// </summary>
internal FunctionInstance InstantiateFunctionObject(JintFunctionDefinition functionDeclaration, EnvironmentRecord env)
{
var functionObject = new ScriptFunctionInstance(
Engine,
functionDeclaration,
env,
functionDeclaration.ThisMode)
{
_realm = _realm
};
functionObject.MakeConstructor();
return(functionObject);
}
/// <summary>
/// https://tc39.es/ecma262/#sec-createdynamicfunction
/// </summary>
private ObjectInstance Construct(JsValue[] arguments, JsValue newTarget)
{
var argCount = arguments.Length;
string p = "";
string body = "";
if (argCount == 1)
{
body = TypeConverter.ToString(arguments[0]);
}
else if (argCount > 1)
{
var firstArg = arguments[0];
p = TypeConverter.ToString(firstArg);
for (var k = 1; k < argCount - 1; k++)
{
var nextArg = arguments[k];
p += "," + TypeConverter.ToString(nextArg);
}
body = TypeConverter.ToString(arguments[argCount - 1]);
}
IFunction function = null;
try
{
string functionExpression;
if (argCount == 0)
{
functionExpression = "function f(){}";
}
else
{
functionExpression = "function f(";
if (p.IndexOf('/') != -1)
{
// ensure comments don't screw up things
functionExpression += "\n" + p + "\n";
}
else
{
functionExpression += p;
}
functionExpression += ")";
if (body.IndexOf('/') != -1)
{
// ensure comments don't screw up things
functionExpression += "{\n" + body + "\n}";
}
else
{
functionExpression += "{" + body + "}";
}
}
var parser = new JavaScriptParser(functionExpression, ParserOptions);
function = (IFunction)parser.ParseScript().Body[0];
}
catch (ParserException)
{
ExceptionHelper.ThrowSyntaxError(_realm);
}
// TODO generators etc, rewrite logic
var proto = GetPrototypeFromConstructor(newTarget, static intrinsics => intrinsics.Function.PrototypeObject);
var functionObject = new ScriptFunctionInstance(
Engine,
function,
_realm.GlobalEnv,
function.Strict,
proto)
{
_realm = _realm
};
functionObject.MakeConstructor();
// the function is not actually a named function
functionObject.SetFunctionName(_functionNameAnonymous, force: true);
return(functionObject);
}
