public ScriptFunction()
{
_varParamKind = ScriptVarParamKind.Direct;
}
protected DynamicCustomFunction(MethodInfo method)
{
Method = method ?? throw new ArgumentNullException(nameof(method));
_returnType = method.ReturnType;
Parameters = method.GetParameters();
#if !SCRIBAN_NO_ASYNC
IsAwaitable = method.ReturnType.GetMethod(nameof(Task.GetAwaiter)) != null;
#endif
_paramsIndex = -1;
if (Parameters.Length > 0)
{
// Check if we have TemplateContext+SourceSpan as first parameters
if (typeof(TemplateContext).IsAssignableFrom(Parameters[0].ParameterType))
{
_hasTemplateContext = true;
if (Parameters.Length > 1)
{
_hasSpan = typeof(SourceSpan).IsAssignableFrom(Parameters[1].ParameterType);
}
}
var lastParam = Parameters[Parameters.Length - 1];
if (lastParam.ParameterType.IsArray)
{
foreach (var param in lastParam.GetCustomAttributes(typeof(ParamArrayAttribute), false))
{
_varParamKind = ScriptVarParamKind.LastParameter;
_paramsElementType = lastParam.ParameterType.GetElementType();
_paramsIndex = Parameters.Length - 1;
break;
}
}
}
_expectedNumberOfParameters = Parameters.Length;
_firstIndexOfUserParameters = 0;
if (_varParamKind == ScriptVarParamKind.None)
{
for (int i = 0; i < Parameters.Length; i++)
{
if (Parameters[i].IsOptional)
{
_optionalParameterCount++;
}
}
}
if (_hasTemplateContext)
{
_firstIndexOfUserParameters++;
if (_hasSpan)
{
_firstIndexOfUserParameters++;
}
}
_expectedNumberOfParameters -= _firstIndexOfUserParameters;
_minimumRequiredParameters = _expectedNumberOfParameters - _optionalParameterCount;
if (_varParamKind == ScriptVarParamKind.LastParameter)
{
_minimumRequiredParameters--;
}
// Compute parameters
_parameterInfos = new ScriptParameterInfo[_expectedNumberOfParameters];
for (int i = 0; i < _expectedNumberOfParameters; i++)
{
var realIndex = _firstIndexOfUserParameters + i;
var parameterInfo = Parameters[realIndex];
var parameterType = realIndex == Parameters.Length - 1 && _varParamKind == ScriptVarParamKind.LastParameter ? _paramsElementType : parameterInfo.ParameterType;
_parameterInfos[i] = parameterInfo.HasDefaultValue
? new ScriptParameterInfo(parameterType, parameterInfo.Name, parameterInfo.DefaultValue)
: new ScriptParameterInfo(parameterType, parameterInfo.Name);
}
}
