public void AycockHorspoolAlgorithmShouldAcceptVulnerableGrammar()
{
var a = new TerminalLexerRule(
new CharacterTerminal('a'),
new TokenName("a"));
ProductionExpression
SPrime = "S'",
S = "S",
A = "A",
E = "E";
SPrime.Rule = S;
S.Rule = (Expr)S | (A + A + A + A);
A.Rule = (Expr)"a" | E;
var expression = new GrammarExpression(
SPrime,
new[] { SPrime, S, A, E });
var grammar = expression.ToGrammar();
var parseEngine = new ParseEngine(grammar);
parseEngine.Pulse(new VerbatimToken(a.TokenName, 0, "a"));
//var privateObject = new PrivateObject(parseEngine);
//var chart = privateObject.GetField("_chart") as Chart;
var chart = parseEngine.Chart;
Assert.IsNotNull(chart);
Assert.AreEqual(2, chart.Count);
Assert.IsTrue(parseEngine.IsAccepted());
}
public Regex Parse(string regularExpression)
{
var grammar = new RegexGrammar();
var parseEngine = new ParseEngine(grammar, new ParseEngineOptions());
var parseRunner = new ParseRunner(parseEngine, regularExpression);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse regular expression. Error at position {parseRunner.Position}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Error parsing regular expression. Error at position {parseRunner.Position}");
}
var parseTree = parseEngine.GetParseTree();
var regexVisitor = new RegexVisitor();
parseTree.Accept(regexVisitor);
return(regexVisitor.Regex);
}
public Regex Parse(string regularExpression)
{
var grammar = new RegexGrammar();
var parseEngine = new ParseEngine(grammar, new ParseEngineOptions(optimizeRightRecursion: true));
var parseRunner = new ParseRunner(parseEngine, regularExpression);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse regular expression. Error at position {parseRunner.Position}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Error parsing regular expression. Error at position {parseRunner.Position}");
}
var parseForest = parseEngine.GetParseForestRootNode();
var parseTree = new InternalTreeNode(
parseForest as IInternalForestNode,
new SelectFirstChildDisambiguationAlgorithm());
var regexVisitor = new RegexVisitor();
parseTree.Accept(regexVisitor);
return(regexVisitor.Regex);
}
public void EbnfParserShouldParseComplexGrammarWithRepeat()
{
var stringBuilder = new StringBuilder()
//.AppendLine("file = ws directives ws ;")
.AppendLine("file = \"1\" { \"2\" } \"1\";");
//.AppendLine("directives = directive { ows directive };")
//.AppendLine("directive = \"0\" | \"1\"; ");
var actual = Parse(stringBuilder.ToString());
var grammar = new EbnfGrammar();
var parseEngine = new ParseEngine(grammar, new ParseEngineOptions(false));
var parseRunner = new ParseRunner(parseEngine, stringBuilder.ToString());
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse Ebnf. Error at position {parseRunner.Position}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Unable to parse Ebnf. Error at position {parseRunner.Position}");
}
var parseForest = parseEngine.GetParseForestRootNode();
var visitor = new LoggingForestNodeVisitor(Console.Out);
parseForest.Accept(visitor);
}
public IEbnfDefinition Parse(string ebnf)
{
var grammar = new EbnfGrammar();
var parseEngine = new ParseEngine(
grammar,
new ParseEngineOptions());
var parseRunner = new ParseRunner(parseEngine, ebnf);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse Ebnf. Error at line {parseRunner.Line}, column {parseRunner.Column}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Ebnf parse not accepted. Error at line {parseRunner.Line}, column {parseRunner.Column}.");
}
var parseTree = parseEngine.GetParseTree();
var ebnfVisitor = new EbnfVisitor();
parseTree.Accept(ebnfVisitor);
return(ebnfVisitor.Definition);
}
#pragma warning disable CC0091 // Use static method
public EbnfDefinition Parse(string ebnf)
{
var grammar = new EbnfGrammar();
var parseEngine = new ParseEngine(
grammar,
new ParseEngineOptions(
optimizeRightRecursion: true,
loggingEnabled: false));
var parseRunner = new ParseRunner(parseEngine, ebnf);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse Ebnf. Error at line {parseRunner.Line}, column {parseRunner.Column}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Ebnf parse not accepted. Error at line {parseRunner.Line}, column {parseRunner.Column}.");
}
var parseForest = parseEngine.GetParseForestRootNode();
var parseTree = new InternalTreeNode(
parseForest as IInternalForestNode,
new SelectFirstChildDisambiguationAlgorithm());
var ebnfVisitor = new EbnfVisitor();
parseTree.Accept(ebnfVisitor);
return(ebnfVisitor.Definition);
}
public void Test_AycockHorspoolAlgorithm_That_Vulnerable_Grammar_Accepts_Input()
{
var a = new TerminalLexerRule(
new Terminal('a'),
new TokenType("a"));
var grammar = new GrammarBuilder("S'")
.Production("S'", r => r
.Rule("S"))
.Production("S", r => r
.Rule("A", "A", "A", "A"))
.Production("A", r => r
.Rule(a)
.Rule("E"))
.Production("E", r => r
.Lambda())
.ToGrammar();
var parseEngine = new ParseEngine(grammar);
parseEngine.Pulse(new Token("a", 0, a.TokenType));
var privateObject = new PrivateObject(parseEngine);
var chart = privateObject.GetField("_chart") as Chart;
Assert.IsNotNull(chart);
Assert.AreEqual(2, chart.Count);
Assert.IsTrue(parseEngine.IsAccepted());
}
public IInternalTreeNode Parse(string source)
{
var grammar = MakeGrammar();
var parseEngine = new ParseEngine(
grammar,
new ParseEngineOptions(loggingEnabled: true));
var parseRunner = new ParseRunner(parseEngine, source);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse expression. Error at line {parseRunner.Line+1}, column {parseRunner.Column+1}.");
}
Console.WriteLine("-----");
Console.ReadKey(true);
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"expression parse not accepted. Error at line {parseRunner.Line+1}, column {parseRunner.Column+1}.");
}
return(parseEngine.GetParseTree());
}
public void ParseEngineCanParseNullableGrammar()
{
var parseEngine = new ParseEngine(new NullableGrammar());
var input = "aaaa";
var tokenType = new TokenType("a");
for (int i = 0; i < input.Length; i++)
{
var result = parseEngine.Pulse(new Token("a", i, tokenType));
Assert.IsTrue(result, $"Error at position {i}");
}
Assert.IsTrue(parseEngine.IsAccepted(), "Parse was not accepted");
}
public void RunParse(IReadOnlyList <IToken> tokens)
{
foreach (var token in tokens)
{
if (!ParseEngine.Pulse(token))
{
Assert.Fail($"Parse Failed at Position {ParseEngine.Location}");
}
}
if (!ParseEngine.IsAccepted())
{
Assert.Fail("Parse was not accepted");
}
}
public void RunParse(IReadOnlyList <IToken> tokens)
{
for (int i = 0; i < tokens.Count; i++)
{
if (!ParseEngine.Pulse(tokens[i]))
{
Assert.Fail($"Parse Failed at Position {ParseEngine.Location}");
}
}
if (!ParseEngine.IsAccepted())
{
Assert.Fail($"Parse was not accepted");
}
}
public void Test_Bnf_That_Parses_Large_Grammar_In_File()
{
var bnf = File.ReadAllText(Path.Combine(TestContext.TestDeploymentDir, "Bnf", "AnsiC.bnf"));
Assert.IsFalse(string.IsNullOrEmpty(bnf));
var grammar = new BnfGrammar();
var parseEngine = new ParseEngine(grammar);
var parseInterface = new ParseInterface(parseEngine, bnf);
while (!parseInterface.EndOfStream())
{
if (!parseInterface.Read())
Assert.Fail("Error Parsing At Position {0}", parseInterface.Position);
}
Assert.IsTrue(parseEngine.IsAccepted());
}
public void Test_NodeWalker_That_Walks_Simple_Regex()
{
var regexGrammar = new RegexGrammar();
var regexParseEngine = new ParseEngine(regexGrammar);
var regexParseInterface = new ParseInterface(regexParseEngine, @"[(]\d[)]");
while (!regexParseInterface.EndOfStream())
{
if (!regexParseInterface.Read())
Assert.Fail("error parsing input at position {0}", regexParseInterface.Position);
}
Assert.IsTrue(regexParseEngine.IsAccepted());
var nodeVisitor = new NodeVisitor();
var root = regexParseEngine.GetRoot();
root.Accept(nodeVisitor);
Assert.AreEqual(34, nodeVisitor.VisitLog.Count);
}
public void BnfShouldParseLargeGrammarInFile()
{
var bnf = File.ReadAllText(Path.Combine(Directory.GetCurrentDirectory(), "Bnf", "AnsiC.bnf"));
Assert.IsFalse(string.IsNullOrEmpty(bnf));
var grammar = new BnfGrammar();
var parseEngine = new ParseEngine(grammar);
var parseRunner = new ParseRunner(parseEngine, bnf);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
Assert.Fail($"Error Parsing At Position {parseRunner.Position}");
}
}
Assert.IsTrue(parseEngine.IsAccepted());
}
private static InternalTreeNode GetTreeNode(Grammar grammar, string input)
{
var parseEngine = new ParseEngine(grammar);
var parseRunner = new ParseRunner(parseEngine, input);
while (!parseRunner.EndOfStream())
{
Assert.IsTrue(parseRunner.Read());
}
Assert.IsTrue(parseEngine.IsAccepted());
var parseForest = parseEngine.GetParseForestRootNode();
Assert.IsNotNull(parseForest);
var internalNode = parseForest;
var treeNode = new InternalTreeNode(internalNode);
return(treeNode);
}
private static InternalTreeNode GetTreeNode(IGrammar grammar, string input)
{
var parseEngine = new ParseEngine(grammar);
var parseRunner = new ParseRunner(parseEngine, input);
while (!parseRunner.EndOfStream())
{
Assert.IsTrue(parseRunner.Read());
}
Assert.IsTrue(parseEngine.IsAccepted());
var parseForest = parseEngine.GetParseForestRootNode();
Assert.IsTrue(parseForest is IInternalForestNode);
var internalNode = parseForest as IInternalForestNode;
var disambiguationAlgorithm = new SelectFirstChildDisambiguationAlgorithm();
var treeNode = new InternalTreeNode(internalNode, disambiguationAlgorithm);
return(treeNode);
}
public void NodeVisitorShouldWalkSimpleRegex()
{
var regexGrammar = new RegexGrammar();
var regexParseEngine = new ParseEngine(regexGrammar);
var regexLexer = new ParseRunner(regexParseEngine, @"[(]\d[)]");
while (!regexLexer.EndOfStream())
{
if (!regexLexer.Read())
{
Assert.Fail($"error parsing input at position {regexLexer.Position}");
}
}
Assert.IsTrue(regexParseEngine.IsAccepted());
var nodeVisitor = new LoggingNodeVisitor(
new SelectFirstChildDisambiguationAlgorithm());
var root = regexParseEngine.GetParseForestRootNode();
root.Accept(nodeVisitor);
Assert.AreEqual(31, nodeVisitor.VisitLog.Count);
}