public void ShouldApplyMultipleMutations()
{
// Arrange
var target = new RegexMutantOrchestrator(@"^[abc]\d?");
// Act
var result = target.Mutate();
// Assert
result.Count().ShouldBeGreaterThanOrEqualTo(4);
}
public void ShouldRemoveAnchor()
{
// Arrange
var target = new RegexMutantOrchestrator("^abc");
// Act
var result = target.Mutate();
// Assert
var mutation = result.ShouldHaveSingleItem();
mutation.OriginalNode.ToString().ShouldBe("^");
mutation.ReplacementNode.ShouldBeNull();
mutation.ReplacementPattern.ShouldBe("abc");
mutation.DisplayName.ShouldBe("Regex anchor removal mutation");
mutation.Description.ShouldBe("Anchor \"^\" was removed at offset 0.");
}
public void ShouldUnnegateNegatedCharacterClass()
{
// Arrange
var target = new RegexMutantOrchestrator("abc[^XY]");
// Act
var result = target.Mutate();
// Assert
var mutation = result.ShouldHaveSingleItem();
mutation.OriginalNode.ToString().ShouldBe("[^XY]");
mutation.ReplacementNode.ToString().ShouldBe("[XY]");
mutation.ReplacementPattern.ShouldBe("abc[XY]");
mutation.DisplayName.ShouldBe("Regex character class negation mutation");
mutation.Description.ShouldBe("Character class \"[^XY]\" was replaced with \"[XY]\" at offset 3.");
}
public void ShouldRemoveLazyQuantifier()
{
// Arrange
var target = new RegexMutantOrchestrator("abcX??");
// Act
var result = target.Mutate();
// Assert
var mutation = result.ShouldHaveSingleItem();
mutation.OriginalNode.ToString().ShouldBe("X??");
mutation.ReplacementNode.ToString().ShouldBe("X");
mutation.ReplacementPattern.ShouldBe("abcX");
mutation.DisplayName.ShouldBe("Regex quantifier removal mutation");
mutation.Description.ShouldBe("Quantifier \"??\" was removed at offset 4.");
}
public void ShouldNegateUnnegatedCharacterClassShorthand()
{
// Arrange
var target = new RegexMutantOrchestrator(@"abc\d");
// Act
var result = target.Mutate();
// Assert
var mutation = result.ShouldHaveSingleItem();
mutation.OriginalNode.ToString().ShouldBe("\\d");
mutation.ReplacementNode.ToString().ShouldBe("\\D");
mutation.ReplacementPattern.ShouldBe("abc\\D");
mutation.DisplayName.ShouldBe("Regex character class shorthand negation mutation");
mutation.Description.ShouldBe("Character class shorthand \"\\d\" was replaced with \"\\D\" at offset 3.");
}
public override IEnumerable <Mutation> ApplyMutations(ObjectCreationExpressionSyntax node)
{
string name = node.Type.ToString();
if (name == typeof(Regex).Name || name == typeof(Regex).FullName)
{
var arguments = node.ArgumentList.Arguments;
var namedArgument = arguments.Where(argument => argument.NameColon?.Name.Identifier.ValueText == PatternArgumentName).FirstOrDefault();
var patternArgument = namedArgument ?? node.ArgumentList.Arguments.FirstOrDefault();
var patternExpression = patternArgument?.Expression;
if (patternExpression?.Kind() == SyntaxKind.StringLiteralExpression)
{
var currentValue = ((LiteralExpressionSyntax)patternExpression).Token.ValueText;
var regexMutantOrchestrator = new RegexMutantOrchestrator(currentValue);
var replacementValues = regexMutantOrchestrator.Mutate();
foreach (RegexMutation regexMutation in replacementValues)
{
try
{
_ = new Regex(regexMutation.ReplacementPattern);
}
catch (ArgumentException exception)
{
Logger.LogDebug($"RegexMutator created mutation {currentValue} -> {regexMutation.ReplacementPattern} which is an invalid regular expression:\n{exception.Message}");
continue;
}
yield return(new Mutation()
{
OriginalNode = patternExpression,
ReplacementNode = SyntaxFactory.LiteralExpression(SyntaxKind.StringLiteralExpression, SyntaxFactory.Literal(regexMutation.ReplacementPattern)),
DisplayName = regexMutation.DisplayName,
Type = Mutator.Regex,
Description = regexMutation.Description
});
}
}
}
}
