137 xunit define codefixes for exceptionasserts assert.throws (#284)

* feat: add xunit Assert.Throws & Assert.ThrowsAsync

* feat: add xunit Assert.ThrowsAny & Assert.ThrowsAnyAsync

* feat: add xunit Assert.Throws*

Author: Meir017

src/FluentAssertions.Analyzers.Tests/Tips/XunitTests.cs

@@ -694,6 +694,81 @@ public void AssertEquivalent_TestAnalyzer(string arguments, string assertion) =>
         public void AssertEquivalent_TestCodeFix(string oldAssertion, string newAssertion)
             => VerifyCSharpFix("object actual, object expected", oldAssertion, newAssertion);
 
+        [DataTestMethod]
+        [DataRow("Action action", "Assert.Throws(typeof(ArgumentException), action);")]
+        [DataRow("Action action, Type exceptionType", "Assert.Throws(exceptionType, action);")]
+        [DataRow("Action action", "Assert.Throws<NullReferenceException>(action);")]
+        [DataRow("Action action", "Assert.Throws<ArgumentException>(\"propertyName\", action);")]
+        [Implemented]
+        public void AssertThrows_TestAnalyzer(string arguments, string assertion) 
+            => VerifyCSharpDiagnostic(arguments, assertion);
+
+        [DataTestMethod]
+        [DataRow("Action action", 
+            /* oldAssertion */ "Assert.Throws(typeof(ArgumentException), action);",
+            /* newAssertion */ "action.Should().ThrowExactly<ArgumentException>();")]
+        [DataRow("Action action", 
+            /* oldAssertion */ "Assert.Throws<NullReferenceException>(action);",
+            /* newAssertion */ "action.Should().ThrowExactly<NullReferenceException>();")]
+        [DataRow("Action action", 
+            /* oldAssertion */ "Assert.Throws<ArgumentException>(\"propertyName\", action);",
+            /* newAssertion */ "action.Should().ThrowExactly<ArgumentException>().WithParameterName(\"propertyName\");")]
+        [Implemented]
+        public void AssertThrows_TestCodeFix(string arguments, string oldAssertion, string newAssertion) 
+            => VerifyCSharpFix(arguments, oldAssertion, newAssertion);
+
+        [DataTestMethod]
+        [DataRow("Func<Task> action", "Assert.ThrowsAsync(typeof(ArgumentException), action);")]
+        [DataRow("Func<Task> action, Type exceptionType", "Assert.ThrowsAsync(exceptionType, action);")]
+        [DataRow("Func<Task> action", "Assert.ThrowsAsync<NullReferenceException>(action);")]
+        [DataRow("Func<Task> action", "Assert.ThrowsAsync<ArgumentException>(\"propertyName\", action);")]
+        [Implemented]
+        public void AssertThrowsAsync_TestAnalyzer(string arguments, string assertion) 
+            => VerifyCSharpDiagnostic(arguments, assertion);
+
+        [DataTestMethod]
+        [DataRow("Func<Task> action", 
+            /* oldAssertion */ "Assert.ThrowsAsync(typeof(ArgumentException), action);",
+            /* newAssertion */ "action.Should().ThrowExactlyAsync<ArgumentException>();")]
+        [DataRow("Func<Task> action", 
+            /* oldAssertion */ "Assert.ThrowsAsync<NullReferenceException>(action);",
+            /* newAssertion */ "action.Should().ThrowExactlyAsync<NullReferenceException>();")]
+        [DataRow("Func<Task> action", 
+            /* oldAssertion */ "Assert.ThrowsAsync<ArgumentException>(\"propertyName\", action);",
+            /* newAssertion */ "action.Should().ThrowExactlyAsync<ArgumentException>().WithParameterName(\"propertyName\");")]
+        [Implemented]
+        public void AssertThrowsAsync_TestCodeFix(string arguments, string oldAssertion, string newAssertion) 
+            => VerifyCSharpFix(arguments, oldAssertion, newAssertion);
+
+        [DataTestMethod]
+        [DataRow("Action action", "Assert.ThrowsAny<NullReferenceException>(action);")]
+        [Implemented]
+        public void AssertThrowsAny_TestAnalyzer(string arguments, string assertion) 
+            => VerifyCSharpDiagnostic(arguments, assertion);
+
+        [DataTestMethod]
+        [DataRow("Action action", 
+            /* oldAssertion */ "Assert.ThrowsAny<NullReferenceException>(action);",
+            /* newAssertion */ "action.Should().Throw<NullReferenceException>();")]
+        [Implemented]
+        public void AssertThrowsAny_TestCodeFix(string arguments, string oldAssertion, string newAssertion) 
+            => VerifyCSharpFix(arguments, oldAssertion, newAssertion);
+
+        [DataTestMethod]
+        [DataRow("Func<Task> action", "Assert.ThrowsAnyAsync<NullReferenceException>(action);")]
+        [Implemented]
+        public void AssertThrowsAnyAsync_TestAnalyzer(string arguments, string assertion) 
+            => VerifyCSharpDiagnostic(arguments, assertion);
+
+        [DataTestMethod]
+        [DataRow("Func<Task> action", 
+            /* oldAssertion */ "Assert.ThrowsAnyAsync<NullReferenceException>(action);",
+            /* newAssertion */ "action.Should().ThrowAsync<NullReferenceException>();")]
+        [Implemented]
+        public void AssertThrowsAnyAsync_TestCodeFix(string arguments, string oldAssertion, string newAssertion) 
+            => VerifyCSharpFix(arguments, oldAssertion, newAssertion);
+
+
         private void VerifyCSharpDiagnostic(string methodArguments, string assertion)
         {
             var source = GenerateCode.XunitAssertion(methodArguments, assertion);

src/FluentAssertions.Analyzers/Tips/DocumentEditorUtils.cs

@@ -15,10 +15,8 @@ public class DocumentEditorUtils
 {
     public static CreateChangedDocument RenameMethodToSubjectShouldAssertion(IInvocationOperation invocation, CodeFixContext context, string newName, int subjectIndex, int[] argumentsToRemove)
     {
-        var invocationExpression = (InvocationExpressionSyntax)invocation.Syntax;
-
-        return async ctx => await RewriteExpression(invocationExpression, [
-            ..Array.ConvertAll(argumentsToRemove, arg => EditAction.RemoveNode(invocationExpression.ArgumentList.Arguments[arg])),
+        return async ctx => await RewriteExpression(invocation, [
+            ..Array.ConvertAll(argumentsToRemove, arg => EditAction.RemoveInvocationArgument(arg)),
             EditAction.SubjectShouldAssertion(subjectIndex, newName)
         ], context, ctx);
     }
@@ -27,33 +25,39 @@ public static CreateChangedDocument RenameGenericMethodToSubjectShouldGenericAss
         => RenameMethodToSubjectShouldGenericAssertion(invocation, invocation.TargetMethod.TypeArguments, context, newName, subjectIndex, argumentsToRemove);
     public static CreateChangedDocument RenameMethodToSubjectShouldGenericAssertion(IInvocationOperation invocation, ImmutableArray<ITypeSymbol> genericTypes, CodeFixContext context, string newName, int subjectIndex, int[] argumentsToRemove)
     {
-        var invocationExpression = (InvocationExpressionSyntax)invocation.Syntax;
-
-        return async ctx => await RewriteExpression(invocationExpression, [
-             ..Array.ConvertAll(argumentsToRemove, arg => EditAction.RemoveNode(invocationExpression.ArgumentList.Arguments[arg])),
-                EditAction.SubjectShouldGenericAssertion(subjectIndex, newName, genericTypes)
+        return async ctx => await RewriteExpression(invocation, [
+            ..Array.ConvertAll(argumentsToRemove, arg => EditAction.RemoveInvocationArgument(arg)),
+            EditAction.SubjectShouldGenericAssertion(subjectIndex, newName, genericTypes)
          ], context, ctx);
     }
 
     public static CreateChangedDocument RenameMethodToSubjectShouldAssertionWithOptionsLambda(IInvocationOperation invocation, CodeFixContext context, string newName, int subjectIndex, int optionsIndex)
     {
-        var invocationExpression = (InvocationExpressionSyntax)invocation.Syntax;
-
-        return async ctx => await RewriteExpression(invocationExpression, [
+        return async ctx => await RewriteExpression(invocation, [
             EditAction.SubjectShouldAssertion(subjectIndex, newName),
             EditAction.CreateEquivalencyAssertionOptionsLambda(optionsIndex)
         ], context, ctx);
     }
 
-    private static async Task<Document> RewriteExpression(InvocationExpressionSyntax invocationExpression, Action<DocumentEditor, InvocationExpressionSyntax>[] actions, CodeFixContext context, CancellationToken cancellationToken)
+    public static async Task<Document> RewriteExpression(IInvocationOperation invocation, Action<EditActionContext>[] actions, CodeFixContext context, CancellationToken cancellationToken)
     {
+        var invocationExpression = (InvocationExpressionSyntax)invocation.Syntax;
+
         var editor = await DocumentEditor.CreateAsync(context.Document, cancellationToken);
+        var editActionContext = new EditActionContext(editor, invocationExpression);
 
         foreach (var action in actions)
         {
-            action(editor, invocationExpression);
+            action(editActionContext);
         }
 
         return editor.GetChangedDocument();
     }
 }
+
+public class EditActionContext(DocumentEditor editor, InvocationExpressionSyntax invocationExpression) {
+    public DocumentEditor Editor { get; } = editor;
+    public InvocationExpressionSyntax InvocationExpression { get; } = invocationExpression;
+    
+    public InvocationExpressionSyntax FluentAssertion { get; set; }
+}

src/FluentAssertions.Analyzers/Tips/Editing/EditAction.cs

@@ -8,15 +8,18 @@ namespace FluentAssertions.Analyzers;
 
 public static class EditAction
 {
-    public static Action<DocumentEditor, InvocationExpressionSyntax> RemoveNode(SyntaxNode node)
-        => (editor, invocationExpression) => editor.RemoveNode(node);
+    public static Action<EditActionContext> RemoveNode(SyntaxNode node)
+        => context => context.Editor.RemoveNode(node);
 
-    public static Action<DocumentEditor, InvocationExpressionSyntax> SubjectShouldAssertion(int argumentIndex, string assertion)
-        => (editor, invocationExpression) => new SubjectShouldAssertionAction(argumentIndex, assertion).Apply(editor, invocationExpression);
+    public static Action<EditActionContext> RemoveInvocationArgument(int argumentIndex)
+        => context => context.Editor.RemoveNode(context.InvocationExpression.ArgumentList.Arguments[argumentIndex]);
 
-    public static Action<DocumentEditor, InvocationExpressionSyntax> SubjectShouldGenericAssertion(int argumentIndex, string assertion, ImmutableArray<ITypeSymbol> genericTypes)
-        => (editor, invocationExpression) => new SubjectShouldGenericAssertionAction(argumentIndex, assertion, genericTypes).Apply(editor, invocationExpression);
+    public static Action<EditActionContext> SubjectShouldAssertion(int argumentIndex, string assertion)
+        => context => new SubjectShouldAssertionAction(argumentIndex, assertion).Apply(context);
 
-    public static Action<DocumentEditor, InvocationExpressionSyntax> CreateEquivalencyAssertionOptionsLambda(int optionsIndex)
-        => (editor, invocationExpression) => new CreateEquivalencyAssertionOptionsLambdaAction(optionsIndex).Apply(editor, invocationExpression);
+    public static Action<EditActionContext> SubjectShouldGenericAssertion(int argumentIndex, string assertion, ImmutableArray<ITypeSymbol> genericTypes)
+        => context => new SubjectShouldGenericAssertionAction(argumentIndex, assertion, genericTypes).Apply(context);
+
+    public static Action<EditActionContext> CreateEquivalencyAssertionOptionsLambda(int optionsIndex)
+        => context => new CreateEquivalencyAssertionOptionsLambdaAction(optionsIndex).Apply(context.Editor, context.InvocationExpression);
 }

src/FluentAssertions.Analyzers/Tips/Editing/RemoveNodeAction.cs

@@ -1,10 +1,11 @@
 using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Editing;
 
 namespace FluentAssertions.Analyzers;
 
-public class SubjectShouldAssertionAction : IEditAction
+public class SubjectShouldAssertionAction
 {
     private readonly int _argumentIndex;
     protected readonly string _assertion;
@@ -15,13 +16,21 @@ public SubjectShouldAssertionAction(int argumentIndex, string assertion)
         _assertion = assertion;
     }
 
-    public void Apply(DocumentEditor editor, InvocationExpressionSyntax invocationExpression)
+    public void Apply(EditActionContext context)
     {
-        var generator = editor.Generator;
-        var subject = invocationExpression.ArgumentList.Arguments[_argumentIndex];
+        var generator = context.Editor.Generator;
+        var arguments = context.InvocationExpression.ArgumentList.Arguments;
+
+        var subject = arguments[_argumentIndex];
         var should = generator.InvocationExpression(generator.MemberAccessExpression(subject.Expression, "Should"));
-        editor.RemoveNode(subject);
-        editor.ReplaceNode(invocationExpression.Expression, generator.MemberAccessExpression(should, GenerateAssertion(generator)).WithTriviaFrom(invocationExpression.Expression));
+        context.Editor.RemoveNode(subject);
+
+        var memberAccess = (MemberAccessExpressionSyntax) generator.MemberAccessExpression(should, GenerateAssertion(generator)).WithTriviaFrom(context.InvocationExpression.Expression);
+
+        context.Editor.ReplaceNode(context.InvocationExpression.Expression, memberAccess);
+        context.FluentAssertion = context.InvocationExpression
+            .WithExpression(memberAccess)
+            .WithArgumentList(SyntaxFactory.ArgumentList(arguments.RemoveAt(_argumentIndex)));
     }
 
     protected virtual SyntaxNode GenerateAssertion(SyntaxGenerator generator) => generator.IdentifierName(_assertion);

src/FluentAssertions.Analyzers/Tips/Editing/SubjectShouldAssertionAction.cs

@@ -1,10 +1,10 @@
 using System.Collections.Immutable;
 using System.Composition;
-using System.Runtime.InteropServices.ComTypes;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CodeFixes;
 using Microsoft.CodeAnalysis.Operations;
 using CreateChangedDocument = System.Func<System.Threading.CancellationToken, System.Threading.Tasks.Task<Microsoft.CodeAnalysis.Document>>;
+using SF = Microsoft.CodeAnalysis.CSharp.SyntaxFactory;
 
 namespace FluentAssertions.Analyzers;
 
@@ -33,7 +33,8 @@ protected override CreateChangedDocument TryComputeFix(IInvocationOperation invo
                 {
                     if (invocation.Arguments[2].Value is ILiteralOperation literal)
                     {
-                        return literal.ConstantValue.Value switch {
+                        return literal.ConstantValue.Value switch
+                        {
                             false => DocumentEditorUtils.RenameMethodToSubjectShouldAssertion(invocation, context, "BeEquivalentTo", subjectIndex: 1, argumentsToRemove: literal.IsImplicit ? [] : [2]),
                             _ => null
                         };
@@ -150,7 +151,52 @@ protected override CreateChangedDocument TryComputeFix(IInvocationOperation invo
                 return DocumentEditorUtils.RenameMethodToSubjectShouldAssertion(invocation, context, "BeInRange", subjectIndex: 0, argumentsToRemove: []);
             case "NotInRange" when ArgumentsCount(invocation, 3): // Assert.NotInRange<T>(T actual, T low, T high)
                 return DocumentEditorUtils.RenameMethodToSubjectShouldAssertion(invocation, context, "NotBeInRange", subjectIndex: 0, argumentsToRemove: []);
+            case "Throws" when ArgumentsCount(invocation, 1): // Assert.Throws<T>(Action testCode) where T : Exception
+                return DocumentEditorUtils.RenameGenericMethodToSubjectShouldGenericAssertion(invocation, context, "ThrowExactly", subjectIndex: 0, argumentsToRemove: []);
+            case "Throws" when ArgumentsAreTypeOf(invocation, t.Type, t.Action): // Assert.Throws(Type exceptionType, Action testCode)
+                {
+                    if (invocation.Arguments[0].Value is not ITypeOfOperation typeOf)
+                    {
+                        return null; // no fix for this
+                    }
+
+                    return DocumentEditorUtils.RenameMethodToSubjectShouldGenericAssertion(invocation, ImmutableArray.Create(typeOf.TypeOperand), context, "ThrowExactly", subjectIndex: 1, argumentsToRemove: [0]);
+                }
+            case "Throws" when ArgumentsAreTypeOf(invocation, t.String, t.Action): // Assert.Throws(string paramName, Action testCode)
+                return RewriteThrowArgumentExceptionAssertion("ThrowExactly");
+            case "ThrowsAsync" when ArgumentsCount(invocation, 1): // Assert.ThrowsAsync<T>(Func<Task> testCode) where T : Exception
+                return DocumentEditorUtils.RenameGenericMethodToSubjectShouldGenericAssertion(invocation, context, "ThrowExactlyAsync", subjectIndex: 0, argumentsToRemove: []);
+            case "ThrowsAsync" when ArgumentsAreTypeOf(invocation, t.Type, t.FuncOfTask): // Assert.ThrowsAsync(Type exceptionType, Func<Task> testCode)
+                {
+                    if (invocation.Arguments[0].Value is not ITypeOfOperation typeOf)
+                    {
+                        return null; // no fix for this
+                    }
+
+                    return DocumentEditorUtils.RenameMethodToSubjectShouldGenericAssertion(invocation, ImmutableArray.Create(typeOf.TypeOperand), context, "ThrowExactlyAsync", subjectIndex: 1, argumentsToRemove: [0]);
+                }
+            case "ThrowsAsync" when ArgumentsAreTypeOf(invocation, t.String, t.FuncOfTask): // Assert.ThrowsAsync(string paramName, Func<Task> testCode)
+                return RewriteThrowArgumentExceptionAssertion("ThrowExactlyAsync");
+            case "ThrowsAny" when ArgumentsCount(invocation, 1): // Assert.ThrowsAny<T>(Action testCode) where T : Exception
+                return DocumentEditorUtils.RenameGenericMethodToSubjectShouldGenericAssertion(invocation, context, "Throw", subjectIndex: 0, argumentsToRemove: []);
+            case "ThrowsAnyAsync" when ArgumentsCount(invocation, 1): // Assert.ThrowsAnyAsync<T>(Func<Task> testCode) where T : Exception
+                return DocumentEditorUtils.RenameGenericMethodToSubjectShouldGenericAssertion(invocation, context, "ThrowAsync", subjectIndex: 0, argumentsToRemove: []);
         }
         return null;
+
+        CreateChangedDocument RewriteThrowArgumentExceptionAssertion(string newName)
+        {
+            return ctx => DocumentEditorUtils.RewriteExpression(invocation, [
+                EditAction.SubjectShouldGenericAssertion(argumentIndex: 1, newName, invocation.TargetMethod.TypeArguments),
+                (editActionContext) =>
+                {
+                    var generator = editActionContext.Editor.Generator;
+                    var withParameterName = generator.MemberAccessExpression(editActionContext.FluentAssertion.WithArgumentList(SF.ArgumentList()), "WithParameterName");
+                    var chainedAssertion = generator.InvocationExpression(withParameterName, editActionContext.InvocationExpression.ArgumentList.Arguments[0]);
+
+                    editActionContext.Editor.ReplaceNode(editActionContext.InvocationExpression, chainedAssertion);
+                }
+            ], context, ctx);
+        }
     }
 }