Fix MA0027 not firing for derived exception types

[Copilot]

MA0027 failed to report throw ex when ex was a derived exception type (e.g. InvalidOperationException). It only triggered for exactly System.Exception.

Root cause: Roslyn wraps the ILocalReferenceOperation in an implicit IConversionOperation (upcasting to Exception) for derived types. The analyzer's early-exit check operation.Exception is not ILocalReferenceOperation never unwrapped that conversion, so derived types were silently skipped.

Fix:

• Call UnwrapImplicitConversionOperations() before the pattern match in DoNotRemoveOriginalExceptionFromThrowStatementAnalyzer

// Before — missed derived types due to implicit upcast wrapping
if (operation.Exception is not ILocalReferenceOperation localReferenceOperation)

// After
if (operation.Exception.UnwrapImplicitConversionOperations() is not ILocalReferenceOperation localReferenceOperation)

• Added test ShouldReportDiagnostic_DerivedException covering the catch (InvalidOperationException ex) { throw ex; } case

Original prompt

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This section details on the original issue you should resolve

<issue_title>MA0027 is only reported when Exception is caught</issue_title>
<issue_description>### Version of the Meziantou.Analyzer NuGet package

3.0.11

Rule Identifier

MA0027

Target Framework

.NET 10.0

C# Language version

C# 14

Description

MA0027 appears to only be reported if the caught exception is exact of the exact type System.Exception and not for a derived type.

Reproduction Steps

Minimal code:

try
{
}
catch (InvalidOperationException ex)
{
    throw ex; // Only CA2200 and S3445 are reported
}

Other information

I see the following options:

• Fix MA0027
• Deprecate it in favor of CA2200</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes MA0027 is only reported when Exception is caught #1025

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