public void GrammarModelGivenNullStartShouldResolveStartFromProductions()
{
var S = new ProductionModel("S");
var A = new ProductionModel("A");
var B = new ProductionModel("B");
S.AddWithAnd(A);
S.AddWithAnd(B);
A.AddWithAnd(new LexerRuleModel(new StringLiteralLexerRule("a")));
A.AddWithAnd(B);
B.AddWithAnd(new LexerRuleModel(new StringLiteralLexerRule("b")));
var grammarModel = new GrammarModel();
grammarModel.Productions.Add(S);
grammarModel.Productions.Add(A);
grammarModel.Productions.Add(B);
var grammar = grammarModel.ToGrammar();
Assert.AreEqual(3, grammar.Productions.Count);
Assert.IsNotNull(grammar.Start);
}
public void GrammarModelConstructorGivenOnlyStartProductionShouldTraverseRecursiveStructureOnlyOnce()
{
var S = new ProductionModel("S");
var A = new ProductionModel("A");
S.AddWithAnd(S);
S.AddWithOr(A);
A.AddWithAnd(new LexerRuleModel(new StringLiteralLexerRule("a")));
var grammarModel = new GrammarModel(S);
var grammar = grammarModel.ToGrammar();
Assert.AreEqual(3, grammar.Productions.Count);
}
public void GrammarModelConstructorGivenOnlyStartProductionShouldDiscoverLinkedProductions()
{
var S = new ProductionModel("S");
var A = new ProductionModel("A");
var B = new ProductionModel("B");
var C = new ProductionModel("C");
S.AddWithAnd(A);
A.AddWithAnd(B);
A.AddWithOr(C);
B.AddWithAnd(new LexerRuleModel(new StringLiteralLexerRule("b")));
C.AddWithAnd(new LexerRuleModel(new StringLiteralLexerRule("c")));
var grammarModel = new GrammarModel(S);
var grammar = grammarModel.ToGrammar();
Assert.AreEqual(5, grammar.Productions.Count);
}
IEnumerable<ProductionModel> Factor(EbnfFactor factor, ProductionModel currentProduction)
{
switch (factor.NodeType)
{
case EbnfNodeType.EbnfFactorGrouping:
var grouping = factor as EbnfFactorGrouping;
foreach (var production in Grouping(grouping, currentProduction))
yield return production;
break;
case EbnfNodeType.EbnfFactorOptional:
var optional = factor as EbnfFactorOptional;
foreach (var production in Optional(optional, currentProduction))
yield return production;
break;
case EbnfNodeType.EbnfFactorRepetition:
var repetition = factor as EbnfFactorRepetition;
foreach (var production in Repetition(repetition, currentProduction))
yield return production;
break;
case EbnfNodeType.EbnfFactorIdentifier:
var identifier = factor as EbnfFactorIdentifier;
var nonTerminal = GetNonTerminalFromQualifiedIdentifier(identifier.QualifiedIdentifier);
currentProduction.AddWithAnd(new NonTerminalModel(nonTerminal));
break;
case EbnfNodeType.EbnfFactorLiteral:
var literal = factor as EbnfFactorLiteral;
var stringLiteralRule = new StringLiteralLexerRule(literal.Value);
currentProduction.AddWithAnd( new LexerRuleModel(stringLiteralRule));
break;
case EbnfNodeType.EbnfFactorRegex:
var regex = factor as EbnfFactorRegex;
var nfa = _thompsonConstructionAlgorithm.Transform(regex.Regex);
var dfa = _subsetConstructionAlgorithm.Transform(nfa);
var dfaLexerRule = new DfaLexerRule(dfa, regex.Regex.ToString());
currentProduction.AddWithAnd(new LexerRuleModel(dfaLexerRule));
break;
}
}
IEnumerable<ProductionModel> Repetition(EbnfFactorRepetition repetition, ProductionModel currentProduction)
{
var name = repetition.ToString();
var nonTerminal = new NonTerminal(name);
var repetitionProduction = new ProductionModel(nonTerminal);
currentProduction.AddWithAnd(new NonTerminalModel(nonTerminal));
var expression = repetition.Expression;
foreach (var production in Expression(expression, repetitionProduction))
yield return production;
repetitionProduction.AddWithAnd(new NonTerminalModel(nonTerminal));
repetitionProduction.Lambda();
yield return repetitionProduction;
}
IEnumerable<ProductionModel> Optional(EbnfFactorOptional optional, ProductionModel currentProduction)
{
var name = optional.ToString();
var nonTerminal = new NonTerminal(name);
var optionalProduction = new ProductionModel(nonTerminal);
currentProduction.AddWithAnd(new NonTerminalModel(nonTerminal));
var expression = optional.Expression;
foreach (var production in Expression(expression, optionalProduction))
yield return production;
optionalProduction.Lambda();
yield return optionalProduction;
}
IEnumerable<ProductionModel> Grouping(EbnfFactorGrouping grouping, ProductionModel currentProduction)
{
var name = grouping.ToString();
var nonTerminal = new NonTerminal(name);
var groupingProduction = new ProductionModel(nonTerminal);
currentProduction.AddWithAnd(new NonTerminalModel(nonTerminal));
var expression = grouping.Expression;
foreach (var production in Expression(expression, groupingProduction))
yield return production;
yield return groupingProduction;
}
public void GrammarModelToGrammarShouldCreateGrammar()
{
var grammarModel = new GrammarModel();
var S = new ProductionModel("S");
var A = new ProductionModel("A");
var B = new ProductionModel("B");
var a = new StringLiteralLexerRule("a");
var b = new StringLiteralLexerRule("b");
var space = new StringLiteralLexerRule(" ");
S.AddWithAnd(A.LeftHandSide);
S.AddWithAnd(B.LeftHandSide);
S.AddWithOr(B.LeftHandSide);
A.AddWithAnd(new LexerRuleModel(a));
B.AddWithAnd(new LexerRuleModel(b));
grammarModel.Productions.Add(S);
grammarModel.Productions.Add(A);
grammarModel.Productions.Add(B);
grammarModel.IgnoreRules.Add(new LexerRuleModel(space));
grammarModel.Start = S;
var grammar = grammarModel.ToGrammar();
Assert.AreEqual(4, grammar.Productions.Count);
Assert.AreEqual(1, grammar.Ignores.Count);
}