public void TestEncodeAndDecode(
[Values(
ParserActionKind.Fail,
ParserActionKind.Accept,
ParserActionKind.Reduce,
ParserActionKind.Shift
)]
ParserActionKind kind,
[Values(0, 1, 1024, ushort.MaxValue)]
int value1)
{
int cell = ParserAction.Encode(kind, value1);
var action = ParserAction.Decode(cell);
if (kind == ParserActionKind.Fail)
{
Assert.AreEqual(kind, action.Kind);
}
else
{
Assert.IsNotNull(action);
Assert.AreEqual(kind, action.Kind);
Assert.AreEqual(value1, action.Value1);
}
Assert.AreEqual(kind, ParserAction.GetKind(cell));
Assert.AreEqual(value1, ParserAction.GetId(cell));
}
private bool TryResolveShiftReduce(int actionX, int actionY, int incomingToken, out int output)
{
output = 0;
int shiftAction, reduceAction;
if (ParserAction.IsShift(actionX) &&
ParserAction.GetKind(actionY) == ParserActionKind.Reduce)
{
shiftAction = actionX;
reduceAction = actionY;
}
else if (ParserAction.IsShift(actionY) &&
ParserAction.GetKind(actionX) == ParserActionKind.Reduce)
{
shiftAction = actionY;
reduceAction = actionX;
}
else
{
// Unsupported conflict type. Use first action
output = actionX;
return(false);
}
var shiftTokenPrecedence = grammar.GetTermPrecedence(incomingToken);
var reduceRulePrecedence = grammar.GetProductionPrecedence(ParserAction.GetId(reduceAction));
if (shiftTokenPrecedence == null && reduceRulePrecedence == null)
{
// In case of conflict prefer shift over reduce
output = shiftAction;
return(false);
}
else if (shiftTokenPrecedence == null)
{
output = reduceAction;
}
else if (reduceRulePrecedence == null)
{
output = shiftAction;
}
else if (Precedence.IsReduce(reduceRulePrecedence, shiftTokenPrecedence))
{
output = reduceAction;
}
else
{
output = shiftAction;
}
return(true);
}