public bool MoveNext()
{
InitlializeTokenBufferIfEmpty();
if (CurrentSymbol == LexiconSymbol.SkipMaterial ||
CurrentSymbol == LexiconSymbol.NA)
{
CurrentTokenBuffer.Clear();
}
while (!TokenStreamReader.EndOfStream)
{
var rawCharacter = TokenStreamReader.Read();
var convertedCharacter = Convert.ToChar(rawCharacter);
var singleToken = LanguageTokens.FindLexiconSymbol(convertedCharacter);
CurrentTokenBuffer.Add(convertedCharacter);
var validTokenBuffer = LanguageTokens.FindLexiconSymbol(CurrentTokenBuffer);
var tempValidTokenBuffer = validTokenBuffer;
var rulesToApply = validTokenBuffer;
rulesToApply = Rules.Select(appliedRule => rulesToApply = appliedRule(singleToken, rulesToApply, CurrentSymbol))
.Where(ls => ls != LexiconSymbol.NA)
.LastOrDefault();
if (rulesToApply != tempValidTokenBuffer)
{
validTokenBuffer = rulesToApply;
}
if (CurrentTokenBuffer.Count > 0 && validTokenBuffer == LexiconSymbol.Assign)
{
CurrentTokenBuffer.RemoveAt(CurrentTokenBuffer.Count - 1);
}
CurrentSymbol = validTokenBuffer;
var mayStopSymbol = LanguageTokens.FindLexiconSymbol(new List <char>()
{
convertedCharacter
});
if (mayStopSymbol == LexiconSymbol.SkipMaterial)
{
CurrentSymbol = mayStopSymbol;
}
if (CurrentSymbol != LexiconSymbol.NA)
{
return(true);
}
}
return(false);
}
internal static IEnumerable <IVbAttribute> GetAttributes(TokenStreamReader reader)
{
bool didEncounterAttributes = false;
while (!reader.IsEOF)
{
IToken token = reader.Read();
switch (token.Type)
{
case TokenType.Word:
{
if (token.EqualsStringInvariant(AnalyzerConstants.Attribute_TokenName))
{
didEncounterAttributes = true;
List <IToken> lineTokens = new List <IToken>();
lineTokens.Add(token);
lineTokens.AddRange(reader.GetUntilEOL());
if (lineTokens.Count == 4)
{
yield return(new VbAttribute()
{
Location = lineTokens[0].Location,
Name = lineTokens[1].Content,
Value = lineTokens[3].Content.Replace("\"", ""),
});
}
}
else
{
/* If we had attributes previously, it is now valid to break execution here.
* VB Classic files always end their "preamble" or "header" with an "Attribute" block.
* After that block, the user code is starting.
*/
if (didEncounterAttributes)
{
yield break;
}
}
}
break;
default:
case TokenType.EOL:
case TokenType.EOF:
continue;
}
}
}
internal static IEnumerable <IVbMethod> GetMethods(TokenStreamReader reader)
{
bool isInMethod = false;
VbMethodType methodType = VbMethodType.Sub;
// Remembers the complete signature for easier construction later.
List <IToken> signatureTokens = new List <IToken>();
IToken previous = null;
VbMethod method = null;
while (!reader.IsEOF)
{
if (!reader.IsBOF)
{
previous = reader.GetPrevious();
}
IToken token = reader.Read();
if (token.Type == TokenType.Word)
{
if (token.EqualsStringInvariant(AnalyzerConstants.Method_Sub) ||
token.EqualsStringInvariant(AnalyzerConstants.Method_Function) ||
token.EqualsStringInvariant(AnalyzerConstants.Method_Property))
{
if (isInMethod)
{
if (previous.EqualsStringInvariant(AnalyzerConstants.End))
{
method.EndStatementLocation = token.Location;
isInMethod = false;
}
continue;
}
isInMethod = true;
methodType = (VbMethodType)Enum.Parse(typeof(VbMethodType), token.Content, true);
method = new VbMethod();
// Properties have Let/Get/Set next... eat that and store it.
if (methodType == VbMethodType.Property)
{
IToken propertyAcc = reader.Read();
method = new VbProperty()
{
Accessor = (VbPropertyAccessor)Enum.Parse(typeof(VbPropertyAccessor), propertyAcc.Content, true),
};
}
method.Visibility = MemberVisibility.Default;
method.Location = token.Location;
method.MethodKind = methodType;
/* Check if there was a visibility-modifier preceeding this method. If so, add it to our signature and correct source location to point to that token.
*/
MemberVisibility visibility = MemberVisibility.Default;
if (TryGetMemberVisibility(previous, out visibility))
{
// Set method location to the previous token (start of line).
method.Location = previous.Location;
}
method.Visibility = visibility;
method.Name = reader.GetUntil(false, null, TokenType.Symbol).GetString();
signatureTokens.AddRange(reader.GetUntilEOL());
bool success = false;
try
{
ParseSignatureIntoMethod(method, signatureTokens);
success = true;
}
catch (Exception)
{
// FIXME: The parser may peek() too far beyond EOF. Need to handle that!
}
if (success)
{
yield return(method);
}
signatureTokens.Clear();
}
}
}
}
private static void ParseSignatureIntoMethod(VbMethod method, IReadOnlyList <IToken> signatureTokens)
{
TokenStreamReader tokenReader = new TokenStreamReader(signatureTokens);
if (tokenReader.Peek().Type == TokenType.Symbol)
{
tokenReader.Read();
}
VbParameter parameter = new VbParameter();
while (!tokenReader.IsEOF)
{
// If it's already the end of the signature, leave the loop.
if (tokenReader.Peek().EqualsStringInvariant(")"))
{
tokenReader.Read();
break;
}
IToken token = tokenReader.Read();
if (IsParameterOptional(token))
{
parameter.IsOptional = true;
continue;
}
VbParameterAccess access = VbParameterAccess.Default;
if (IsParamaterAccessToken(token, out access))
{
parameter.Access = access;
continue;
}
/* Assume that if the next parameter is "As", then this is a parameter name.
* Also watch out for implicit parameters, which are parameters that don't declare a type (variant).
*/
IToken peek = tokenReader.Peek();
if (peek == null)
{
break;
}
if (peek.EqualsStringInvariant("As") ||
peek.Type == TokenType.Symbol)
{
parameter.Name = token.Content;
parameter.Location = token.Location;
if (peek.Type == TokenType.Symbol)
{
parameter.Type = VbTypes.Variant;
// Eat token.
tokenReader.Read();
}
else
{
// Eat token.
tokenReader.Read();
parameter.Type = new VbType()
{
TypeName = ReadUntilEOLIntoString(tokenReader, Delimiters)
};
}
/* Look ahead for an optional value declaration if this parameter is optional.
*/
if (parameter.IsOptional)
{
if (tokenReader.GetPrevious().Content == "=")
{
parameter.OptionalDefaultValue = ReadUntilEOLIntoString(tokenReader, Delimiters);
}
}
/* Add parameter and reset instance.
*/
method.AddParameter(parameter);
parameter = new VbParameter();
continue;
}
}
/* Specify "void" return "type" in advance; may be overridden.
*/
method.ReturnType = VbTypes.Void;
bool canHaveReturnType = false;
if (method.MethodKind == VbMethodType.Function)
{
canHaveReturnType = true;
}
else if (method.MethodKind == VbMethodType.Property)
{
IVbProperty property = (IVbProperty)method;
if (property.Accessor == VbPropertyAccessor.Get)
{
canHaveReturnType = true;
}
}
/* Look for a return type.
*/
if (canHaveReturnType)
{
method.ReturnType = VbTypes.Variant;
if (!tokenReader.IsEOF)
{
var returnTokens = tokenReader.GetUntilEOL().ToArray();
if (returnTokens[0].EqualsStringInvariant("As"))
{
string typeName = string.Concat(returnTokens.Skip(1).Select(_ => _.Content));
method.ReturnType = new VbType()
{
TypeName = typeName
};
}
}
}
}