public IParseResult TryConvertToTokenStream(IStringStream inputStream, out ITokenStream tokenStream)
{
if (inputStream == null)
{
throw new ArgumentNullException();
}
tokenStream = new TokenStream();
while (!inputStream.IsEmpty())
{
var character = inputStream.LookAhead(0);
if (!_parserFactory.TryGetTokenParser(character, out var tokenParser))
{
return(new FailureParseResult(inputStream.CurrentPosition, RegSeedErrorType.InvalidInput));
}
var parseResult = tokenParser.TryGetToken(inputStream, out var token);
if (!parseResult.IsSuccess)
{
return(parseResult);
}
tokenStream.Append(token);
}
return(new SuccessParseResult(inputStream.CurrentPosition));
}
public void Pop_IncrementsCurrentPositionByOne_WhenAllStreamElementsAreCharacters()
{
var stream = new TokenStream();
stream.Append(Substitute.For <IToken>()).Append(Substitute.For <IToken>());
stream.Pop();
stream.Pop();
var result = stream.CurrentPosition;
Assert.AreEqual(2, result);
}
public void Pop_ReturnsFirstElement()
{
var token1 = Substitute.For <IToken>();
var token2 = Substitute.For <IToken>();
var token3 = Substitute.For <IToken>();
var stream = new TokenStream();
stream.Append(token1).Append(token2).Append(token3);
var result1 = stream.Pop();
var result2 = stream.Pop();
var result3 = stream.Pop();
Assert.AreEqual(token1, result1);
Assert.AreEqual(token2, result2);
Assert.AreEqual(token3, result3);
}