private static async Task VerifyFixAsync(Solution sln, IReadOnlyList <ImmutableArray <Diagnostic> > diagnostics, DiagnosticAnalyzer analyzer, CodeFixProvider fix, string fixedCode, string fixTitle = null, AllowCompilationErrors allowCompilationErrors = AllowCompilationErrors.No)
{
var fixableDiagnostics = diagnostics.SelectMany(x => x)
.Where(x => fix.FixableDiagnosticIds.Contains(x.Id))
.ToArray();
if (fixableDiagnostics.Length == 0)
{
var message = $"Code analyzed with {analyzer} did not generate any diagnostics fixable by {fix}.{Environment.NewLine}" +
$"The analyzed code contained the following diagnostics: {{{string.Join(", ", diagnostics.SelectMany(x => x).Select(d => d.Id))}}}{Environment.NewLine}" +
$"The code fix supports the following diagnostics: {{{string.Join(", ", fix.FixableDiagnosticIds)}}}";
throw new AssertException(message);
}
if (fixableDiagnostics.Length > 1)
{
var message = $"Code analyzed with {analyzer} generated more than one diagnostic fixable by {fix}.{Environment.NewLine}" +
$"The analyzed code contained the following diagnostics: {{{string.Join(", ", diagnostics.SelectMany(x => x).Select(d => d.Id))}}}{Environment.NewLine}" +
$"The code fix supports the following diagnostics: {{{string.Join(", ", fix.FixableDiagnosticIds)}}}{Environment.NewLine}" +
$"Maybe you meant to call AnalyzerAssert.FixAll?";
throw new AssertException(message);
}
var diagnostic = fixableDiagnostics.Single();
var fixedSolution = await Fix.ApplyAsync(sln, fix, diagnostic, fixTitle).ConfigureAwait(false);
if (ReferenceEquals(sln, fixedSolution))
{
throw new AssertException($"{fix} did not change any document.");
}
var fixedSource = await CodeReader.GetStringFromDocumentAsync(
fixedSolution.GetDocument(sln.GetDocument(diagnostic.Location.SourceTree).Id),
Formatter.Annotation,
CancellationToken.None)
.ConfigureAwait(false);
CodeAssert.AreEqual(fixedCode, fixedSource);
if (allowCompilationErrors == AllowCompilationErrors.No)
{
await VerifyNoCompilerErrorsAsync(fix, fixedSolution).ConfigureAwait(false);
}
}
private static async Task AreEqualAsync(IReadOnlyList <string> expected, Solution actual, string?messageHeader)
{
var actualCount = actual.Projects.SelectMany(x => x.Documents).Count();
if (expected.Count != actualCount)
{
throw new AssertException($"Expected {expected.Count} documents the fixed solution has {actualCount} documents.");
}
foreach (var project in actual.Projects)
{
foreach (var document in project.Documents)
{
var fixedSource = await CodeReader.GetStringFromDocumentAsync(document, CancellationToken.None).ConfigureAwait(false);
CodeAssert.AreEqual(FindExpected(fixedSource), fixedSource, messageHeader);
}
}
string FindExpected(string fixedSource)
{
var fixedNamespace = CodeReader.Namespace(fixedSource);
var fixedFileName = CodeReader.FileName(fixedSource);
var match = expected.FirstOrDefault(x => x == fixedSource);
if (match != null)
{
return(match);
}
foreach (var candidate in expected)
{
if (CodeReader.Namespace(candidate) == fixedNamespace &&
CodeReader.FileName(candidate) == fixedFileName)
{
return(candidate);
}
}
throw new AssertException($"The fixed solution contains a document {fixedFileName} in namespace {fixedNamespace} that is not in the expected documents.");
}
}
/// <summary>
/// Create a new instance of <see cref="ExpectedDiagnostic"/> with position.
/// </summary>
/// <param name="codeWithErrorsIndicated">The code with error position indicated..</param>
/// <param name="cleanedSources"><paramref name="codeWithErrorsIndicated"/> without errors indicated.</param>
/// <returns>A new instance of <see cref="ExpectedDiagnostic"/>.</returns>
public ExpectedDiagnostic WithPositionFromCodeWithErrorsIndicated(string codeWithErrorsIndicated, out string cleanedSources)
{
var positions = CodeReader.FindLinePositions(codeWithErrorsIndicated).ToArray();
if (positions.Length == 0)
{
throw new ArgumentException("Expected one error position indicated, was zero.", nameof(codeWithErrorsIndicated));
}
if (positions.Length > 1)
{
throw new ArgumentException($"Expected one error position indicated, was {positions.Length}.", nameof(codeWithErrorsIndicated));
}
cleanedSources = codeWithErrorsIndicated.Replace("↓", string.Empty);
var fileName = CodeReader.FileName(codeWithErrorsIndicated);
var position = positions[0];
return(new ExpectedDiagnostic(this.Id, this.Message, new FileLinePositionSpan(fileName, position, position)));
}
/// <summary>
/// Get the expected diagnostics and cleaned sources.
/// </summary>
/// <param name="analyzerId">The descriptor diagnosticId that is expected to produce diagnostics.</param>
/// <param name="message">The expected message for the diagnostics, can be null.</param>
/// <param name="code">The code with errors indicated.</param>
/// <returns>An instance of <see cref="DiagnosticsAndSources"/>.</returns>
public static DiagnosticsAndSources CreateFromCodeWithErrorsIndicated(string analyzerId, string?message, IReadOnlyList <string> code)
{
if (analyzerId is null)
{
throw new ArgumentNullException(nameof(analyzerId));
}
if (code is null)
{
throw new ArgumentNullException(nameof(code));
}
var diagnostics = new List <ExpectedDiagnostic>();
var cleanedSources = new List <string>();
foreach (var source in code)
{
var positions = CodeReader.FindLinePositions(source).ToArray();
if (positions.Length == 0)
{
cleanedSources.Add(source);
continue;
}
cleanedSources.Add(source.Replace("↓", string.Empty));
var fileName = CodeReader.FileName(source);
diagnostics.AddRange(positions.Select(p => new ExpectedDiagnostic(analyzerId, message, new FileLinePositionSpan(fileName, p, p))));
}
if (diagnostics.Count == 0)
{
throw new InvalidOperationException("Expected code to have at least one error position indicated with '↓'");
}
return(new DiagnosticsAndSources(diagnostics, cleanedSources));
}
public SourceMetadata(string code)
{
this.Code = code;
this.FileName = CodeReader.FileName(code);
this.Namespace = CodeReader.Namespace(code);
}
private static async Task AssertNoCompilerErrorsAsync(CodeFixProvider codeFix, Solution fixedSolution)
{
var diagnostics = await Analyze.GetDiagnosticsAsync(fixedSolution).ConfigureAwait(false);
var introducedDiagnostics = diagnostics
.SelectMany(x => x)
.Where(IsIncluded)
.ToArray();
if (introducedDiagnostics.Select(x => x.Id)
.Except(DiagnosticSettings.AllowedErrorIds())
.Any())
{
var errorBuilder = StringBuilderPool.Borrow();
errorBuilder.AppendLine($"{codeFix} introduced syntax error{(introducedDiagnostics.Length > 1 ? "s" : string.Empty)}.");
foreach (var introducedDiagnostic in introducedDiagnostics)
{
var errorInfo = await introducedDiagnostic.ToStringAsync(fixedSolution).ConfigureAwait(false);
errorBuilder.AppendLine($"{errorInfo}");
}
errorBuilder.AppendLine("First source file with error is:");
var sources = await Task.WhenAll(fixedSolution.Projects.SelectMany(p => p.Documents).Select(d => CodeReader.GetStringFromDocumentAsync(d, Formatter.Annotation, CancellationToken.None)));
var lineSpan = introducedDiagnostics.First().Location.GetMappedLineSpan();
var match = sources.SingleOrDefault(x => CodeReader.FileName(x) == lineSpan.Path);
errorBuilder.Append(match);
errorBuilder.AppendLine();
throw AssertException.Create(errorBuilder.Return());
}
}
/// <summary>
/// Create a <see cref="Solution"/> for <paramref name="code"/>
/// Each unique namespace in <paramref name="code"/> is added as a project.
/// </summary>
/// <param name="code">The code to create the solution from.</param>
/// <param name="compilationOptions">The <see cref="CSharpCompilationOptions"/>.</param>
/// <param name="metadataReferences">The metadata references.</param>
/// <param name="languageVersion">The <see cref="LanguageVersion"/>.</param>
/// <returns>A <see cref="Solution"/>.</returns>
public static Solution CreateSolution(IEnumerable <string> code, CSharpCompilationOptions compilationOptions, IEnumerable <MetadataReference> metadataReferences = null, LanguageVersion languageVersion = LanguageVersion.Latest)
{
var solutionInfo = SolutionInfo.Create(
SolutionId.CreateNewId("Test.sln"),
VersionStamp.Default,
projects: GetProjectInfos());
var solution = EmptySolution;
foreach (var projectInfo in solutionInfo.Projects)
{
solution = solution.AddProject(projectInfo.WithProjectReferences(FindReferences(projectInfo)));
}
return(solution);
IEnumerable <ProjectInfo> GetProjectInfos()
{
var byNamespace = new SortedDictionary <string, List <string> >();
foreach (var document in code)
{
var ns = CodeReader.Namespace(document);
if (byNamespace.TryGetValue(ns, out var doc))
{
doc.Add(document);
}
else
{
byNamespace[ns] = new List <string> {
document
};
}
}
var byProject = new SortedDictionary <string, List <KeyValuePair <string, List <string> > > >();
foreach (var kvp in byNamespace)
{
var last = byProject.Keys.LastOrDefault();
var ns = kvp.Key;
if (last != null &&
ns.Contains(last))
{
byProject[last].Add(kvp);
}
else
{
byProject.Add(ns, new List <KeyValuePair <string, List <string> > > {
kvp
});
}
}
foreach (var kvp in byProject)
{
var assemblyName = kvp.Key;
var projectId = ProjectId.CreateNewId(assemblyName);
yield return(ProjectInfo.Create(
projectId,
VersionStamp.Default,
assemblyName,
assemblyName,
LanguageNames.CSharp,
compilationOptions: compilationOptions,
metadataReferences: metadataReferences,
documents: kvp.Value.SelectMany(x => x.Value)
.Select(
x =>
{
var documentName = CodeReader.FileName(x);
return DocumentInfo.Create(
DocumentId.CreateNewId(projectId, documentName),
documentName,
sourceCodeKind: SourceCodeKind.Regular,
loader: new StringLoader(x));
}))
.WithParseOptions(CSharpParseOptions.Default.WithLanguageVersion(languageVersion)));
}
}
IEnumerable <ProjectReference> FindReferences(ProjectInfo projectInfo)
{
var references = new List <ProjectReference>();
foreach (var other in solutionInfo.Projects.Where(x => x.Id != projectInfo.Id))
{
if (projectInfo.Documents.Any(x => x.TextLoader is StringLoader stringLoader &&
(stringLoader.Code.Contains($"using {other.Name};") ||
stringLoader.Code.Contains($"{other.Name}."))))
{
references.Add(new ProjectReference(other.Id));
}
}
return(references);
}
}
/// <summary>
/// Verify that two strings of code are equal. Agnostic to end of line characters.
/// </summary>
/// <param name="expected">The expected code.</param>
/// <param name="actual">The actual code.</param>
/// <param name="messageHeader">The first line to add to the exception message on error.</param>
internal static void AreEqual(string expected, string actual, string messageHeader)
{
var expectedPos = 0;
var actualPos = 0;
var line = 1;
while (expectedPos < expected.Length && actualPos < actual.Length)
{
var ec = expected[expectedPos];
var ac = actual[actualPos];
if (ec == '\r' || ac == '\r')
{
if (ec == '\r')
{
expectedPos++;
}
if (ac == '\r')
{
actualPos++;
}
continue;
}
if (ec != ac)
{
if (IsAt(expected, expectedPos, "\\r") ||
IsAt(actual, actualPos, "\\r"))
{
if (IsAt(expected, expectedPos, "\\r"))
{
expectedPos += 2;
}
if (IsAt(actual, actualPos, "\\r"))
{
actualPos += 2;
}
continue;
}
var errorBuilder = StringBuilderPool.Borrow();
if (messageHeader != null)
{
errorBuilder.AppendLine(messageHeader);
}
if (!IsSingleLine(expected) ||
!IsSingleLine(actual))
{
errorBuilder.AppendLine(
CodeReader.TryGetFileName(expected, out var fileName)
? $"Mismatch on line {line} of file {fileName}."
: $"Mismatch on line {line}.");
}
var expectedLine = expected.Split('\n')[line - 1].Trim('\r');
var actualLine = actual.Split('\n')[line - 1].Trim('\r');
var diffPos = DiffPos(expectedLine, actualLine);
errorBuilder.AppendLine($"Expected: {expectedLine}")
.AppendLine($"Actual: {actualLine}")
.AppendLine($" {new string(' ', diffPos)}^");
if (!IsSingleLine(expected) ||
!IsSingleLine(actual))
{
errorBuilder.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine();
}
throw new AssertException(errorBuilder.Return());
}
if (ec == '\n')
{
line++;
}
expectedPos++;
actualPos++;
}
while (expectedPos < expected.Length && expected[expectedPos] == '\r')
{
expectedPos++;
}
while (actualPos < actual.Length && actual[actualPos] == '\r')
{
actualPos++;
}
if (expectedPos == expected.Length && actualPos == actual.Length)
{
return;
}
var messageBuilder = StringBuilderPool.Borrow();
if (messageHeader != null)
{
messageBuilder.AppendLine(messageHeader);
}
messageBuilder.AppendLine(CodeReader.TryGetFileName(expected, out var name) ? $"Mismatch at end of file {name}." : "Mismatch at end.")
.Append("Expected: ").AppendLine(GetEnd(expected))
.Append("Actual: ").AppendLine(GetEnd(actual))
.AppendLine($" {new string(' ', DiffPos(GetEnd(expected), GetEnd(actual)))}^");
if (!IsSingleLine(expected) ||
!IsSingleLine(actual))
{
messageBuilder.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine();
}
throw new AssertException(messageBuilder.Return());
bool IsSingleLine(string text)
{
bool foundNewLine = false;
foreach (var c in text)
{
switch (c)
{
case '\r':
case '\n':
foundNewLine = true;
break;
default:
if (foundNewLine)
{
return(false);
}
break;
}
}
return(true);
}
int DiffPos(string expectedLine, string actualLine)
{
var diffPos = Math.Min(expectedLine.Length, actualLine.Length);
for (var i = 0; i < Math.Min(expectedLine.Length, actualLine.Length); i++)
{
if (expectedLine[i] != actualLine[i])
{
diffPos = i;
break;
}
}
return(diffPos);
}
string GetEnd(string text)
{
bool lastLine = false;
var builder = StringBuilderPool.Borrow();
for (var i = text.Length - 1; i >= 0; i--)
{
switch (text[i])
{
case '\r':
if (lastLine)
{
return(builder.Return());
}
builder.Insert(0, "\\r");
break;
case '\n':
if (lastLine)
{
return(builder.Return());
}
builder.Insert(0, "\\n");
break;
default:
lastLine = true;
builder.Insert(0, text[i]);
break;
}
}
return(builder.Return());
}
}
private static async Task VerifyNoCompilerErrorsAsync(CodeFixProvider fix, Solution fixedSolution)
{
var diagnostics = await Analyze.GetDiagnosticsAsync(fixedSolution).ConfigureAwait(false);
var introducedDiagnostics = diagnostics
.SelectMany(x => x)
.Where(IsIncluded)
.ToArray();
if (introducedDiagnostics.Select(x => x.Id)
#pragma warning disable CS0618 // Suppress until removed. Will be replaced with Metadatareferences.FromAttributes()
.Except(SuppressedDiagnostics)
#pragma warning restore CS0618 // Suppress until removed. Will be replaced with Metadatareferences.FromAttributes()
.Any())
{
var errorBuilder = StringBuilderPool.Borrow();
errorBuilder.AppendLine($"{fix.GetType().Name} introduced syntax error{(introducedDiagnostics.Length > 1 ? "s" : string.Empty)}.");
foreach (var introducedDiagnostic in introducedDiagnostics)
{
errorBuilder.AppendLine($"{introducedDiagnostic.ToErrorString()}");
}
var sources = await Task.WhenAll(fixedSolution.Projects.SelectMany(p => p.Documents).Select(d => CodeReader.GetStringFromDocumentAsync(d, CancellationToken.None)));
errorBuilder.AppendLine("First source file with error is:");
var lineSpan = introducedDiagnostics.First().Location.GetMappedLineSpan();
if (sources.TrySingle(x => CodeReader.FileName(x) == lineSpan.Path, out var match))
{
errorBuilder.AppendLine(match);
}
else if (sources.TryFirst(x => CodeReader.FileName(x) == lineSpan.Path, out _))
{
errorBuilder.AppendLine($"Found more than one document for {lineSpan.Path}.");
foreach (string source in sources.Where(x => CodeReader.FileName(x) == lineSpan.Path))
{
errorBuilder.AppendLine(source);
}
}
else
{
errorBuilder.AppendLine($"Did not find a single document for {lineSpan.Path}.");
}
throw new AssertException(errorBuilder.Return());
}
}
/// <summary>
/// Verify that two strings of code are equal. Agnostic to end of line characters.
/// </summary>
/// <param name="expected">The expected code.</param>
/// <param name="actual">The actual code.</param>
/// <param name="messageHeader">The first line to add to the exception message on error.</param>
internal static void AreEqual(string expected, string actual, string messageHeader)
{
var expectedPos = 0;
var actualPos = 0;
var line = 1;
while (expectedPos < expected.Length && actualPos < actual.Length)
{
var ec = expected[expectedPos];
var ac = actual[actualPos];
if (ec == '\r' || ac == '\r')
{
if (ec == '\r')
{
expectedPos++;
}
if (ac == '\r')
{
actualPos++;
}
continue;
}
if (ec != ac)
{
var errorBuilder = StringBuilderPool.Borrow();
if (messageHeader != null)
{
errorBuilder.AppendLine(messageHeader);
}
errorBuilder.AppendLine($"Mismatch on line {line} of file {CodeReader.FileName(expected)}");
var expectedLine = expected.Split('\n')[line - 1].Trim('\r');
var actualLine = actual.Split('\n')[line - 1].Trim('\r');
var diffPos = Math.Min(expectedLine.Length, actualLine.Length);
for (var i = 0; i < Math.Min(expectedLine.Length, actualLine.Length); i++)
{
if (expectedLine[i] != actualLine[i])
{
diffPos = i;
break;
}
}
errorBuilder.AppendLine($"Expected: {expectedLine}")
.AppendLine($"Actual: {actualLine}")
.AppendLine($" {new string(' ', diffPos)}^")
.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine();
throw AssertException.Create(errorBuilder.Return());
}
if (ec == '\n')
{
line++;
}
expectedPos++;
actualPos++;
}
while (expectedPos < expected.Length && expected[expectedPos] == '\r')
{
expectedPos++;
}
while (actualPos < actual.Length && actual[actualPos] == '\r')
{
actualPos++;
}
if (expectedPos == expected.Length && actualPos == actual.Length)
{
return;
}
if (messageHeader != null)
{
var message = StringBuilderPool.Borrow()
.AppendLine(messageHeader)
.AppendLine($"Mismatch at end of file {CodeReader.FileName(expected)}")
.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine()
.Return();
throw AssertException.Create(message);
}
else
{
var message = StringBuilderPool.Borrow()
.AppendLine($"Mismatch at end of file {CodeReader.FileName(expected)}")
.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine()
.Return();
throw AssertException.Create(message);
}
}
/// <summary>
/// Verifies that
/// 1. <paramref name="solution"/> produces the expected diagnostics
/// 2. The code fix fixes the code.
/// </summary>
/// <param name="analyzer">The analyzer to run on the code..</param>
/// <param name="fix">The code fix to apply.</param>
/// <param name="expectedDiagnostic">The expected diagnostic.</param>
/// <param name="solution">The code with error positions indicated.</param>
/// <param name="fixedCode">The expected code produced by the code fix.</param>
/// <param name="fixTitle">The title of the fix to apply if more than one.</param>
/// <param name="allowCompilationErrors">If compilation errors are accepted in the fixed code.</param>
public static void CodeFix(DiagnosticAnalyzer analyzer, CodeFixProvider fix, ExpectedDiagnostic expectedDiagnostic, Solution solution, string fixedCode, string fixTitle = null, AllowCompilationErrors allowCompilationErrors = AllowCompilationErrors.No)
{
VerifyAnalyzerSupportsDiagnostic(analyzer, expectedDiagnostic);
VerifyCodeFixSupportsAnalyzer(analyzer, fix);
var diagnostics = Analyze.GetDiagnostics(analyzer, solution);
var diagnosticsAndSources = DiagnosticsAndSources.Create(expectedDiagnostic, solution.Projects.SelectMany(x => x.Documents).Select(x => CodeReader.GetCode(x, null)).ToArray());
VerifyDiagnostics(diagnosticsAndSources, diagnostics);
VerifyFix(solution, diagnostics, analyzer, fix, fixedCode, fixTitle, allowCompilationErrors);
}
/// <summary>
/// Verify that two strings of code are equal. Agnostic to end of line characters.
/// </summary>
/// <param name="expected">The expected code.</param>
/// <param name="actual">The actual code.</param>
/// <param name="messageHeader">The first line to add to the exception message on error.</param>
internal static void AreEqual(string expected, string actual, string?messageHeader)
{
var expectedPos = 0;
var actualPos = 0;
var line = 1;
while (expectedPos < expected.Length && actualPos < actual.Length)
{
var ec = expected[expectedPos];
var ac = actual[actualPos];
if (ec == '\r' || ac == '\r')
{
if (ec == '\r')
{
expectedPos++;
}
if (ac == '\r')
{
actualPos++;
}
continue;
}
if (ec != ac)
{
if (IsAt(expected, expectedPos, "\\r") ||
IsAt(actual, actualPos, "\\r"))
{
if (IsAt(expected, expectedPos, "\\r"))
{
expectedPos += 2;
}
if (IsAt(actual, actualPos, "\\r"))
{
actualPos += 2;
}
continue;
}
var errorBuilder = StringBuilderPool.Borrow();
if (messageHeader != null)
{
errorBuilder.AppendLine(messageHeader);
}
if (!IsSingleLine(expected) ||
!IsSingleLine(actual))
{
errorBuilder.AppendLine(
CodeReader.TryGetFileName(expected, out var fileName)
? $"Mismatch on line {line} of file {fileName}."
: $"Mismatch on line {line}.");
}
var expectedLine = expected.Split('\n')[line - 1].Trim('\r');
var actualLine = actual.Split('\n')[line - 1].Trim('\r');
var diffPos = DiffPos(expectedLine, actualLine);
errorBuilder.AppendLine($"Expected: {expectedLine}")
.AppendLine($"Actual: {actualLine}")
.AppendLine($" {new string(' ', diffPos)}^");
if (!IsSingleLine(expected) ||
!IsSingleLine(actual))
{
errorBuilder.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine();
}
throw new AssertException(errorBuilder.Return());
}
if (ec == '\n')
{
line++;
}
expectedPos++;
actualPos++;
}
while (expectedPos < expected.Length && expected[expectedPos] == '\r')
{
expectedPos++;
}
while (actualPos < actual.Length && actual[actualPos] == '\r')
{
actualPos++;
}
if (expectedPos == expected.Length && actualPos == actual.Length)
{
return;
}
var messageBuilder = StringBuilderPool.Borrow();
if (messageHeader != null)
{
messageBuilder.AppendLine(messageHeader);
}
messageBuilder.AppendLine(CodeReader.TryGetFileName(expected, out var name) ? $"Mismatch at end of file {name}." : "Mismatch at end.")
.Append("Expected: ").AppendLine(GetEnd(expected))
.Append("Actual: ").AppendLine(GetEnd(actual))
.AppendLine($" {new string(' ', DiffPos(GetEnd(expected), GetEnd(actual)))}^");
if (!IsSingleLine(expected) ||
!IsSingleLine(actual))
{
messageBuilder.AppendLine("Expected:")
.Append(expected)
.AppendLine()
.AppendLine("Actual:")
.Append(actual)
.AppendLine();
}
throw new AssertException(messageBuilder.Return());