BizHawk/ExternalProjects/BizHawk.Analyzer/NoTargetTypedThrowAnalyzer.cs

59 lines
1.9 KiB
C#

namespace BizHawk.Analyzers;
using System.Collections.Immutable;
using Microsoft.CodeAnalysis;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.Diagnostics;
using Microsoft.CodeAnalysis.Operations;
[DiagnosticAnalyzer(LanguageNames.CSharp)]
public sealed class NoTargetTypedThrowAnalyzer : DiagnosticAnalyzer
{
private const string ERR_MSG_IMPLICIT = "Specify `Exception` (or a more precise type) explicitly";
private static readonly DiagnosticDescriptor DiagNoTargetTypedThrow = new(
id: "BHI1007",
title: "Don't use target-typed new for throw expressions",
messageFormat: "{0}",
category: "Usage",
defaultSeverity: DiagnosticSeverity.Warning,
isEnabledByDefault: true);
public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics { get; } = ImmutableArray.Create(DiagNoTargetTypedThrow);
public override void Initialize(AnalysisContext context)
{
context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
context.EnableConcurrentExecution();
context.RegisterOperationAction(
oac =>
{
var exceptionOp = ((IThrowOperation) oac.Operation).Exception;
if (exceptionOp is null) return; // re-`throw;`
void Fail(string message)
=> oac.ReportDiagnostic(Diagnostic.Create(DiagNoTargetTypedThrow, exceptionOp.Syntax.GetLocation(), message));
switch (exceptionOp.Kind)
{
case OperationKind.ObjectCreation:
case OperationKind.Invocation:
case OperationKind.PropertyReference:
case OperationKind.LocalReference:
return;
case OperationKind.Conversion:
if (((IConversionOperation) exceptionOp).Operand.Syntax
.IsKind(SyntaxKind.ImplicitObjectCreationExpression))
{
break;
}
return;
default:
Fail($"Argument to throw expression was of an unexpected kind: {exceptionOp.GetType().FullName}");
return;
}
Fail(ERR_MSG_IMPLICIT);
},
OperationKind.Throw);
}
}