src/Compilers/VisualBasic/Test/Semantic/Semantics/UseSiteErrorTests.vb - main - githubmirror/roslyn

src/Compilers/VisualBasic/Test/Semantic/Semantics/UseSiteErrorTests.vb
1 771 строка67 KB
Tomáš Matoušek
Refactoring of extension methods in source packages (#78620) - take 2 (#78894)
26 июн 2025, 18:42
26 июн 2025, 18:4205fc006
' Licensed to the .NET Foundation under one or more agreements.
' The .NET Foundation licenses this file to you under the MIT license.
' See the LICENSE file in the project root for more information.

Imports Microsoft.CodeAnalysis.Collections
Imports Microsoft.CodeAnalysis.Test.Utilities
Imports Roslyn.Test.Utilities

Namespace Microsoft.CodeAnalysis.VisualBasic.UnitTests.Semantics

    Public Class UseSiteErrorTests
        Inherits BasicTestBase

        <Fact>
        Public Sub TestPropertyAccessorModOpt()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits ILErrors.ClassProperties
    Shared Sub M(c As ILErrors.ClassProperties)
        c.GetSet1 = c.GetSet1
        c.GetSet2 = c.GetSet2
        Dim value As Integer = c.GetSet3
        c.GetSet3 = value
    End Sub
    Sub M()
        Dim value As Integer = GetSet3
        GetSet3 = value
    End Sub
End Class
    </file>
            </compilation>
            Dim compilation = CompileWithMissingReference(source)
            CompilationUtils.AssertTheseDiagnostics(compilation,
<expected>
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        c.GetSet1 = c.GetSet1
        ~~~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        c.GetSet1 = c.GetSet1
                    ~~~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        c.GetSet2 = c.GetSet2
        ~~~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        c.GetSet2 = c.GetSet2
                    ~~~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Dim value As Integer = c.GetSet3
                               ~~~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        c.GetSet3 = value
        ~~~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Dim value As Integer = GetSet3
                               ~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        GetSet3 = value
        ~~~~~~~
</expected>)
        End Sub

        <Fact>
        Public Sub TestOverrideMethodReturnType()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits CSharpErrors.ClassMethods

    Public Overrides Function ReturnType1() As UnavailableClass
        Return Nothing
    End Function

    Public Overrides Function ReturnType2() As UnavailableClass()
        Return Nothing
    End Function
End Class
    </file>
            </compilation>

            ' CONSIDER: Dev10 doesn't report the cascading errors (ERR_InvalidOverrideDueToReturn2)
            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "ReturnType1").WithArguments("Public Overrides Function ReturnType1() As UnavailableClass", "Public Overridable Overloads Function ReturnType1() As UnavailableClass"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "ReturnType2").WithArguments("Public Overrides Function ReturnType2() As UnavailableClass()", "Public Overridable Overloads Function ReturnType2() As UnavailableClass()"))
        End Sub

        <Fact>
        Public Sub TestOverrideMethodReturnTypeModOpt()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits ILErrors.ClassMethods

    Public Overrides Function ReturnType1() As Integer
        Return 0
    End Function

    Public Overrides Function ReturnType2() As Integer()
        Return Nothing
    End Function
End Class
    </file>
            </compilation>

            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ReturnType1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ReturnType2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"))
        End Sub

        <Fact>
        Public Sub TestOverrideMethodParameterType()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits CSharpErrors.ClassMethods

    Public Overrides Sub ParameterType1(x As UnavailableClass)
    End Sub

    Public Overrides Sub ParameterType2(x As UnavailableClass())
    End Sub
End Class
    </file>
            </compilation>

            ' CONSIDER: Dev10 doesn't report the cascading errors (ERR_OverrideNotNeeded3)
            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_OverrideNotNeeded3, "ParameterType1").WithArguments("sub", "ParameterType1"),
                Diagnostic(ERRID.ERR_OverrideNotNeeded3, "ParameterType2").WithArguments("sub", "ParameterType2"))
        End Sub

        <Fact>
        Public Sub TestOverrideMethodParameterTypeModOpt()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits ILErrors.ClassMethods

    Public Overrides Sub ParameterType1(x As Integer)
    End Sub

    Public Overrides Sub ParameterType2(x As Integer())
    End Sub
End Class
    </file>
            </compilation>

            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ParameterType1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ParameterType2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"))
        End Sub

        <Fact>
        Public Sub TestImplementMethod()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Implements CSharpErrors.InterfaceMethods

    Public Function ReturnType1() As UnavailableClass Implements CSharpErrors.InterfaceMethods.ReturnType1
        Return Nothing
    End Function
    Public Function ReturnType2() As UnavailableClass() Implements CSharpErrors.InterfaceMethods.ReturnType2
        Return Nothing
    End Function

    Public Sub ParameterType1(x As UnavailableClass) Implements CSharpErrors.InterfaceMethods.ParameterType1
    End Sub
    Public Sub ParameterType2(x As UnavailableClass()) Implements CSharpErrors.InterfaceMethods.ParameterType2
    End Sub
End Class
    </file>
            </compilation>

            ' CONSIDER: Dev10 doesn't report the cascading errors (ERR_IdentNotMemberOfInterface4, ERR_UnimplementedMember3)
            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceMethods.ReturnType1").WithArguments("ReturnType1", "ReturnType1", "function", "InterfaceMethods"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceMethods.ReturnType2").WithArguments("ReturnType2", "ReturnType2", "function", "InterfaceMethods"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceMethods.ParameterType1").WithArguments("ParameterType1", "ParameterType1", "sub", "InterfaceMethods"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceMethods.ParameterType2").WithArguments("ParameterType2", "ParameterType2", "sub", "InterfaceMethods"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceMethods").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceMethods").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceMethods").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceMethods").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"))
        End Sub

        <Fact>
        Public Sub TestImplementMethodModOpt()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Implements ILErrors.InterfaceMethods

    Public Function ReturnType1() As Integer Implements ILErrors.InterfaceMethods.ReturnType1
        Return 0
    End Function
    Public Function ReturnType2() As Integer() Implements ILErrors.InterfaceMethods.ReturnType2
        Return Nothing
    End Function

    Public Sub ParameterType1(x As Integer) Implements ILErrors.InterfaceMethods.ParameterType1
    End Sub
    Public Sub ParameterType2(x As Integer()) Implements ILErrors.InterfaceMethods.ParameterType2
    End Sub
End Class
    </file>
            </compilation>

            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ReturnType1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ReturnType2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ParameterType1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "ParameterType2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"))
        End Sub

        <Fact>
        Public Sub TestOverridePropertyType()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits CSharpErrors.ClassProperties

    Public Overrides ReadOnly Property Get1 As UnavailableClass
        Get
            Return Nothing
        End Get
    End Property
    Public Overrides ReadOnly Property Get2 As UnavailableClass()
        Get
            Return Nothing
        End Get
    End Property

    Public Overrides WriteOnly Property Set1 As UnavailableClass
        Set(value As UnavailableClass)
        End Set
    End Property

    Public Overrides WriteOnly Property Set2 As UnavailableClass()
        Set(value As UnavailableClass())
        End Set
    End Property

    Public Overrides Property GetSet1 As UnavailableClass
        Get
            Return Nothing
        End Get
        Set(value As UnavailableClass)
        End Set
    End Property
    Public Overrides Property GetSet2 As UnavailableClass()
        Get
            Return Nothing
        End Get
        Set(value As UnavailableClass())
        End Set
    End Property
End Class
    </file>
            </compilation>

            ' CONSIDER: it might be nice to suppress the extra ERR_UndefinedType1 that we see for each setter
            ' CONSIDER: Dev10 doesn't report the cascading errors (ERR_InvalidOverrideDueToReturn2)
            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "Get1").WithArguments("Public Overrides ReadOnly Property Get1 As UnavailableClass", "Public Overridable Overloads ReadOnly Property Get1 As UnavailableClass"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "Get2").WithArguments("Public Overrides ReadOnly Property Get2 As UnavailableClass()", "Public Overridable Overloads ReadOnly Property Get2 As UnavailableClass()"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "Set1").WithArguments("Public Overrides WriteOnly Property Set1 As UnavailableClass", "Public Overridable Overloads WriteOnly Property Set1 As UnavailableClass"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "Set2").WithArguments("Public Overrides WriteOnly Property Set2 As UnavailableClass()", "Public Overridable Overloads WriteOnly Property Set2 As UnavailableClass()"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "GetSet1").WithArguments("Public Overrides Property GetSet1 As UnavailableClass", "Public Overridable Overloads Property GetSet1 As UnavailableClass"),
                Diagnostic(ERRID.ERR_InvalidOverrideDueToReturn2, "GetSet2").WithArguments("Public Overrides Property GetSet2 As UnavailableClass()", "Public Overridable Overloads Property GetSet2 As UnavailableClass()"))
        End Sub

        <Fact>
        Public Sub TestOverridePropertyTypeModOpt()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits ILErrors.ClassProperties

    Public Overrides ReadOnly Property Get1 As Integer
        Get
            Return 0
        End Get
    End Property
    Public Overrides ReadOnly Property Get2 As Integer()
        Get
            Return Nothing
        End Get
    End Property

    Public Overrides WriteOnly Property Set1 As Integer
        Set(value As Integer)
        End Set
    End Property

    Public Overrides WriteOnly Property Set2 As Integer()
        Set(value As Integer())
        End Set
    End Property

    Public Overrides Property GetSet1 As Integer
        Get
            Return 0
        End Get
        Set(value As Integer)
        End Set
    End Property
    Public Overrides Property GetSet2 As Integer()
        Get
            Return Nothing
        End Get
        Set(value As Integer())
        End Set
    End Property
End Class
    </file>
            </compilation>

            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "Get1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "Get2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "Set1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "Set2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "GetSet1").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "GetSet2").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"))
        End Sub

        <Fact>
        Public Sub TestImplementProperty()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Implements CSharpErrors.InterfaceProperties

    Public ReadOnly Property Get1 As UnavailableClass Implements CSharpErrors.InterfaceProperties.Get1
        Get
            Return Nothing
        End Get
    End Property
    Public ReadOnly Property Get2 As UnavailableClass() Implements CSharpErrors.InterfaceProperties.Get2
        Get
            Return Nothing
        End Get
    End Property

    Public WriteOnly Property Set1 As UnavailableClass Implements CSharpErrors.InterfaceProperties.Set1
        Set(value As UnavailableClass)
        End Set
    End Property

    Public WriteOnly Property Set2 As UnavailableClass() Implements CSharpErrors.InterfaceProperties.Set2
        Set(value As UnavailableClass())
        End Set
    End Property

    Public Property GetSet1 As UnavailableClass Implements CSharpErrors.InterfaceProperties.GetSet1
        Get
            Return Nothing
        End Get
        Set(value As UnavailableClass)
        End Set
    End Property
    Public Property GetSet2 As UnavailableClass() Implements CSharpErrors.InterfaceProperties.GetSet2
        Get
            Return Nothing
        End Get
        Set(value As UnavailableClass())
        End Set
    End Property
End Class
    </file>
            </compilation>

            ' CONSIDER: it might be nice to suppress the extra ERR_UndefinedType1 that we see for each setter
            ' CONSIDER: Dev10 doesn't report the cascading errors (ERR_IdentNotMemberOfInterface4, ERR_UnimplementedMember3)
            CompileWithMissingReference(source).VerifyDiagnostics(
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_UndefinedType1, "UnavailableClass").WithArguments("UnavailableClass"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceProperties.Get1").WithArguments("Get1", "Get1", "property", "InterfaceProperties"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceProperties.Get2").WithArguments("Get2", "Get2", "property", "InterfaceProperties"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceProperties.Set1").WithArguments("Set1", "Set1", "property", "InterfaceProperties"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceProperties.Set2").WithArguments("Set2", "Set2", "property", "InterfaceProperties"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceProperties.GetSet1").WithArguments("GetSet1", "GetSet1", "property", "InterfaceProperties"),
                Diagnostic(ERRID.ERR_IdentNotMemberOfInterface4, "CSharpErrors.InterfaceProperties.GetSet2").WithArguments("GetSet2", "GetSet2", "property", "InterfaceProperties"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceProperties").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceProperties").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceProperties").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceProperties").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceProperties").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"),
                Diagnostic(ERRID.ERR_UnreferencedAssembly3, "CSharpErrors.InterfaceProperties").WithArguments("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", "UnavailableClass"))
        End Sub

        <Fact>
        Public Sub TestImplementPropertyModOpt()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Implements ILErrors.InterfaceProperties

    Public ReadOnly Property Get1 As Integer Implements ILErrors.InterfaceProperties.Get1
        Get
            Return 0
        End Get
    End Property
    Public ReadOnly Property Get2 As Integer() Implements ILErrors.InterfaceProperties.Get2
        Get
            Return Nothing
        End Get
    End Property

    Public WriteOnly Property Set1 As Integer Implements ILErrors.InterfaceProperties.Set1
        Set(value As Integer)
        End Set
    End Property

    Public WriteOnly Property Set2 As Integer() Implements ILErrors.InterfaceProperties.Set2
        Set(value As Integer())
        End Set
    End Property

    Public Property GetSet1 As Integer Implements ILErrors.InterfaceProperties.GetSet1
        Get
            Return 0
        End Get
        Set(value As Integer)
        End Set
    End Property
    Public Property GetSet2 As Integer() Implements ILErrors.InterfaceProperties.GetSet2
        Get
            Return Nothing
        End Get
        Set(value As Integer())
        End Set
    End Property
End Class
    </file>
            </compilation>

            CompileWithMissingReference(source).AssertTheseDiagnostics(
<expected>
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
    Public ReadOnly Property Get1 As Integer Implements ILErrors.InterfaceProperties.Get1
                             ~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Get
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
    Public ReadOnly Property Get2 As Integer() Implements ILErrors.InterfaceProperties.Get2
                             ~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Get
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
    Public WriteOnly Property Set1 As Integer Implements ILErrors.InterfaceProperties.Set1
                              ~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Set(value As Integer)
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
    Public WriteOnly Property Set2 As Integer() Implements ILErrors.InterfaceProperties.Set2
                              ~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Set(value As Integer())
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
    Public Property GetSet1 As Integer Implements ILErrors.InterfaceProperties.GetSet1
                    ~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Get
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Set(value As Integer)
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
    Public Property GetSet2 As Integer() Implements ILErrors.InterfaceProperties.GetSet2
                    ~~~~~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Get
        ~~~
BC30652: Reference required to assembly 'Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' containing the type 'UnavailableClass'. Add one to your project.
        Set(value As Integer())
        ~~~
</expected>)
        End Sub

        <Fact()>
        Public Sub CompilerGeneratedAttributeNotRequired()
            Dim compilation1 = CompilationUtils.CreateEmptyCompilationWithReferences(
            <compilation name="CompilerGeneratedAttributeNotRequired">
                <file name="a.vb">
Class C
    Property Goo as Integer 
End Class
    </file>
            </compilation>, Enumerable.Empty(Of MetadataReference)())

            AssertTheseDiagnostics(compilation1, <errors>
BC30002: Type 'System.Void' is not defined.
Class C
~~~~~~~~
BC31091: Import of type 'Object' from assembly or module 'CompilerGeneratedAttributeNotRequired.dll' failed.
Class C
      ~
BC30002: Type 'System.Void' is not defined.
    Property Goo as Integer 
    ~~~~~~~~~~~~~~~~~~~~~~~
BC30002: Type 'System.Int32' is not defined.
    Property Goo as Integer 
                    ~~~~~~~                                                    
                                                </errors>)

            ' the important bit here is, that there is no complaint about a missing CompilerGeneratedAttribute..ctor.
            For Each diag In compilation1.GetDiagnostics()
                Assert.DoesNotContain("System.Runtime.CompilerServices.CompilerGeneratedAttribute", diag.GetMessage, StringComparison.Ordinal)
            Next
        End Sub

        ''' <summary>
        ''' First, compile the provided source with all assemblies and confirm that there are no errors.
        ''' Then, compile the provided source again without the unavailable assembly and return the result.
        ''' </summary>
        Private Shared Function CompileWithMissingReference(sources As XElement) As VisualBasicCompilation
            Dim unavailableAssemblyReference = TestReferences.SymbolsTests.UseSiteErrors.Unavailable
            Dim csharpAssemblyReference = TestReferences.SymbolsTests.UseSiteErrors.CSharp
            Dim ilAssemblyReference = TestReferences.SymbolsTests.UseSiteErrors.IL
            Dim successfulCompilation = CreateCompilationWithMscorlib40AndReferences(sources, New MetadataReference() {unavailableAssemblyReference, csharpAssemblyReference, ilAssemblyReference})
            successfulCompilation.VerifyDiagnostics()
            Dim failingCompilation = CreateCompilationWithMscorlib40AndReferences(sources, New MetadataReference() {csharpAssemblyReference, ilAssemblyReference})
            Return failingCompilation
        End Function

        <Fact>
        <WorkItem(14267, "https://github.com/dotnet/roslyn/issues/14267")>
        Public Sub MissingTypeKindBasisTypes()
            Dim source1 =
            <compilation>
                <file name="a.vb">
Public Structure A
End Structure

Public Enum B
    x
End Enum

Public Class C
End Class

Public Delegate Sub D()

Public Interface I1
End Interface
    </file>
            </compilation>

            Dim compilation1 = CreateEmptyCompilationWithReferences(source1, options:=TestOptions.ReleaseDll, references:={MinCorlibRef})
            compilation1.VerifyEmitDiagnostics()

            Assert.Equal(TypeKind.Struct, compilation1.GetTypeByMetadataName("A").TypeKind)
            Assert.Equal(TypeKind.Enum, compilation1.GetTypeByMetadataName("B").TypeKind)
            Assert.Equal(TypeKind.Class, compilation1.GetTypeByMetadataName("C").TypeKind)
            Assert.Equal(TypeKind.Delegate, compilation1.GetTypeByMetadataName("D").TypeKind)
            Assert.Equal(TypeKind.Interface, compilation1.GetTypeByMetadataName("I1").TypeKind)

            Dim source2 =
            <compilation>
                <file name="a.vb">
Interface I2
    Function M(a As A, b As B, c As C, d As D) As I1
End Interface
    </file>
            </compilation>

            Dim compilation2 = CreateEmptyCompilationWithReferences(source2, options:=TestOptions.ReleaseDll, references:={compilation1.EmitToImageReference(), MinCorlibRef})

            compilation2.VerifyEmitDiagnostics()
            CompileAndVerify(compilation2)

            Assert.Equal(TypeKind.Struct, compilation2.GetTypeByMetadataName("A").TypeKind)
            Assert.Equal(TypeKind.Enum, compilation2.GetTypeByMetadataName("B").TypeKind)
            Assert.Equal(TypeKind.Class, compilation2.GetTypeByMetadataName("C").TypeKind)
            Assert.Equal(TypeKind.Delegate, compilation2.GetTypeByMetadataName("D").TypeKind)
            Assert.Equal(TypeKind.Interface, compilation2.GetTypeByMetadataName("I1").TypeKind)

            Dim compilation3 = CreateEmptyCompilationWithReferences(source2, options:=TestOptions.ReleaseDll, references:={compilation1.ToMetadataReference(), MinCorlibRef})

            compilation3.VerifyEmitDiagnostics()
            CompileAndVerify(compilation3)

            Assert.Equal(TypeKind.Struct, compilation3.GetTypeByMetadataName("A").TypeKind)
            Assert.Equal(TypeKind.Enum, compilation3.GetTypeByMetadataName("B").TypeKind)
            Assert.Equal(TypeKind.Class, compilation3.GetTypeByMetadataName("C").TypeKind)
            Assert.Equal(TypeKind.Delegate, compilation3.GetTypeByMetadataName("D").TypeKind)
            Assert.Equal(TypeKind.Interface, compilation3.GetTypeByMetadataName("I1").TypeKind)

            Dim compilation4 = CreateEmptyCompilationWithReferences(source2, options:=TestOptions.ReleaseDll, references:={compilation1.EmitToImageReference()})

            compilation4.AssertTheseDiagnostics(<expected>
BC30652: Reference required to assembly 'mincorlib, Version=0.0.0.0, Culture=neutral, PublicKeyToken=ce65828c82a341f2' containing the type 'ValueType'. Add one to your project.
    Function M(a As A, b As B, c As C, d As D) As I1
                    ~
BC30652: Reference required to assembly 'mincorlib, Version=0.0.0.0, Culture=neutral, PublicKeyToken=ce65828c82a341f2' containing the type '[Enum]'. Add one to your project.
    Function M(a As A, b As B, c As C, d As D) As I1
                            ~
BC30652: Reference required to assembly 'mincorlib, Version=0.0.0.0, Culture=neutral, PublicKeyToken=ce65828c82a341f2' containing the type 'MulticastDelegate'. Add one to your project.
    Function M(a As A, b As B, c As C, d As D) As I1
                                            ~
                                                </expected>)

            Dim a = compilation4.GetTypeByMetadataName("A")
            Dim b = compilation4.GetTypeByMetadataName("B")
            Dim c = compilation4.GetTypeByMetadataName("C")
            Dim d = compilation4.GetTypeByMetadataName("D")
            Dim i1 = compilation4.GetTypeByMetadataName("I1")
            Assert.Equal(TypeKind.Class, a.TypeKind)
            Assert.NotNull(a.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Class, b.TypeKind)
            Assert.NotNull(b.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Class, c.TypeKind)
            Assert.Null(c.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Class, d.TypeKind)
            Assert.NotNull(d.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Interface, i1.TypeKind)
            Assert.Null(i1.GetUseSiteErrorInfo())

            Dim compilation5 = CreateEmptyCompilationWithReferences(source2, options:=TestOptions.ReleaseDll, references:={compilation1.ToMetadataReference()})

            compilation5.VerifyEmitDiagnostics()
            ' ILVerify: no corlib
            CompileAndVerify(compilation5, verify:=Verification.FailsILVerify)

            Assert.Equal(TypeKind.Struct, compilation5.GetTypeByMetadataName("A").TypeKind)
            Assert.Equal(TypeKind.Enum, compilation5.GetTypeByMetadataName("B").TypeKind)
            Assert.Equal(TypeKind.Class, compilation5.GetTypeByMetadataName("C").TypeKind)
            Assert.Equal(TypeKind.Delegate, compilation5.GetTypeByMetadataName("D").TypeKind)
            Assert.Equal(TypeKind.Interface, compilation5.GetTypeByMetadataName("I1").TypeKind)

            Dim compilation6 = CreateEmptyCompilationWithReferences(source2, options:=TestOptions.ReleaseDll, references:={compilation1.EmitToImageReference(), MscorlibRef})

            compilation6.AssertTheseDiagnostics(<expected>
BC30652: Reference required to assembly 'mincorlib, Version=0.0.0.0, Culture=neutral, PublicKeyToken=ce65828c82a341f2' containing the type 'ValueType'. Add one to your project.
    Function M(a As A, b As B, c As C, d As D) As I1
                    ~
BC30652: Reference required to assembly 'mincorlib, Version=0.0.0.0, Culture=neutral, PublicKeyToken=ce65828c82a341f2' containing the type '[Enum]'. Add one to your project.
    Function M(a As A, b As B, c As C, d As D) As I1
                            ~
BC30652: Reference required to assembly 'mincorlib, Version=0.0.0.0, Culture=neutral, PublicKeyToken=ce65828c82a341f2' containing the type 'MulticastDelegate'. Add one to your project.
    Function M(a As A, b As B, c As C, d As D) As I1
                                            ~
                                                </expected>)

            a = compilation6.GetTypeByMetadataName("A")
            b = compilation6.GetTypeByMetadataName("B")
            c = compilation6.GetTypeByMetadataName("C")
            d = compilation6.GetTypeByMetadataName("D")
            i1 = compilation6.GetTypeByMetadataName("I1")
            Assert.Equal(TypeKind.Class, a.TypeKind)
            Assert.NotNull(a.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Class, b.TypeKind)
            Assert.NotNull(b.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Class, c.TypeKind)
            Assert.Null(c.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Class, d.TypeKind)
            Assert.NotNull(d.GetUseSiteErrorInfo())
            Assert.Equal(TypeKind.Interface, i1.TypeKind)
            Assert.Null(i1.GetUseSiteErrorInfo())

            Dim compilation7 = CreateEmptyCompilationWithReferences(source2, options:=TestOptions.ReleaseDll, references:={compilation1.ToMetadataReference(), MscorlibRef})

            compilation7.VerifyEmitDiagnostics()
            CompileAndVerify(compilation7)

            Assert.Equal(TypeKind.Struct, compilation7.GetTypeByMetadataName("A").TypeKind)
            Assert.Equal(TypeKind.Enum, compilation7.GetTypeByMetadataName("B").TypeKind)
            Assert.Equal(TypeKind.Class, compilation7.GetTypeByMetadataName("C").TypeKind)
            Assert.Equal(TypeKind.Delegate, compilation7.GetTypeByMetadataName("D").TypeKind)
            Assert.Equal(TypeKind.Interface, compilation7.GetTypeByMetadataName("I1").TypeKind)
        End Sub

        <Fact, WorkItem(15435, "https://github.com/dotnet/roslyn/issues/15435")>
        Public Sub TestGettingAssemblyIdsFromDiagnostic1()
            Dim source =
            <compilation>
                <file name="a.vb">
Class C
    Inherits ILErrors.ClassMethods

    Public Overrides Function ReturnType1() As Integer
        Return 0
    End Function

    Public Overrides Function ReturnType2() As Integer()
        Return Nothing
    End Function
End Class
    </file>
            </compilation>

            Dim compilation = CompileWithMissingReference(source)
            Dim Diagnostics = compilation.GetDiagnostics()
            Assert.True(Diagnostics.Any(Function(d) d.Code = ERRID.ERR_UnreferencedAssembly3))

            For Each d In Diagnostics
                If d.Code = ERRID.ERR_UnreferencedAssembly3 Then
                    Dim actualAssemblyId = compilation.GetUnreferencedAssemblyIdentities(d).Single()
                    Dim expectedAssemblyId As AssemblyIdentity = Nothing
                    AssemblyIdentity.TryParseDisplayName("Unavailable, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null", expectedAssemblyId)

                    Assert.Equal(actualAssemblyId, expectedAssemblyId)
                End If
            Next
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_01()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
      .maxstack  8
      ldc.i4.s   123
      ret
    } 
} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Function get_P() As Integer
        Return Nothing
    End Function
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'get_P' has a return type that is not supported or parameter types that are not supported.
    Overrides Function get_P() As Integer
                       ~~~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_02()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
      .maxstack  8
      ldc.i4.s   123
      ret
    } 

    .property instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Readonly Property P As Integer
        Get
            Return Nothing
        End Get
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30643: Property 'CL1.P' is of an unsupported type.
    Overrides Readonly Property P As Integer
                                ~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_03()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
      .maxstack  8
      ldc.i4.s   123
      ret
    } 

    .property instance int32 P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Readonly Property P As Integer
        Get
            Return Nothing
        End Get
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_04()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) set_P(int32 x) cil managed
    {
      .maxstack  8
      ret
    } 

    .property instance int32 P()
    {
      .set instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides WriteOnly Property P As Integer
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Set
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_05()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
      .maxstack  8
      ldc.i4.s   123
      ret
    } 

    .method public hidebysig newslot virtual
            instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) set_P(int32 x) cil managed
    {
      .maxstack  8
      ret
    } 

    .property instance int32 P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
      .set instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Property P As Integer
        Get
            Return Nothing
        End Get
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Set
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_06()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance int32 get_P() cil managed
    {
      .maxstack  8
      ldc.i4.s   123
      ret
    } 

    .method public hidebysig newslot virtual
            instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) set_P(int32 x) cil managed
    {
      .maxstack  8
      ret
    } 

    .property instance int32 P()
    {
      .get instance int32 CL1::get_P()
      .set instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Property P As Integer
        Get
            Return Nothing
        End Get
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)
            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Set
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_07()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig newslot virtual
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
      .maxstack  8
      ldc.i4.s   123
      ret
    } 

    .method public hidebysig newslot virtual
            instance void set_P(int32 x) cil managed
    {
      .maxstack  8
      ret
    } 

    .property instance int32 P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
      .set instance void CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Property P As Integer
        Get
            Return Nothing
        End Get
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub OverrideWithModreq_08()
            Dim ilSource = <![CDATA[
.class public auto ansi beforefieldinit CL1
       extends[mscorlib] System.Object
{
    .method public hidebysig specialname rtspecialname
            instance void  .ctor() cil managed
    {
      // Code size       7 (0x7)
      .maxstack  1
      IL_0000: ldarg.0
      IL_0001: call instance void[mscorlib] System.Object::.ctor()
      IL_0006: ret
    }

    .method public hidebysig specialname newslot virtual 
        instance void add_E (
            class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst) 'value'
        ) cil managed 
    {
      ret
    }

    .method public hidebysig specialname newslot virtual 
        instance void remove_E (
            class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst) 'value'
        ) cil managed 
    {
      ret
    }

    .event [mscorlib]System.Action E
    {
        .addon instance void CL1::add_E(class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst))
        .removeon instance void CL1::remove_E(class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst))
    }
} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Inherits CL1

    Overrides Custom Event E As System.Action
        AddHandler(d As System.Action)
        End AddHandler
        RemoveHandler(d As System.Action)
        End RemoveHandler
        RaiseEvent
        End RaiseEvent
    End Event
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30243: 'Overrides' is not valid on an event declaration.
    Overrides Custom Event E As System.Action
    ~~~~~~~~~
BC40004: event 'E' conflicts with event 'E' in the base class 'CL1' and should be declared 'Shadows'.
    Overrides Custom Event E As System.Action
                           ~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_01()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
    } 
} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Function get_P() As Integer Implements CL1.get_P
        Return Nothing
    End Function
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'get_P' has a return type that is not supported or parameter types that are not supported.
    Function get_P() As Integer Implements CL1.get_P
             ~~~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_02()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
    } 

    .property instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    ReadOnly Property P As Integer Implements CL1.P
        Get
            Return Nothing
        End Get
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30643: Property 'CL1.P' is of an unsupported type.
    ReadOnly Property P As Integer Implements CL1.P
                      ~
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_03()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
    } 

    .property instance int32 P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    ReadOnly Property P As Integer Implements CL1.P
        Get
            Return Nothing
        End Get
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_04()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) set_P(int32 x) cil managed
    {
    } 

    .property instance int32 P()
    {
      .set instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    WriteOnly Property P As Integer Implements CL1.P
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Set
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_05()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
    } 

    .method public hidebysig newslot specialname abstract virtual 
            instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) set_P(int32 x) cil managed
    {
    } 

    .property instance int32 P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
      .set instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Property P As Integer Implements CL1.P
        Get
            Return Nothing
        End Get
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseEmitDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Set
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_06()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance int32 get_P() cil managed
    {
    } 

    .method public hidebysig newslot specialname abstract virtual 
            instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) set_P(int32 x) cil managed
    {
    } 

    .property instance int32 P()
    {
      .get instance int32 CL1::get_P()
      .set instance void modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Property P As Integer Implements CL1.P
        Get
            Return Nothing
        End Get
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Set
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_07()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{
    .method public hidebysig newslot specialname abstract virtual 
            instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) get_P() cil managed
    {
    } 

    .method public hidebysig newslot specialname abstract virtual 
            instance void set_P(int32 x) cil managed
    {
    } 

    .property instance int32 P()
    {
      .get instance int32 modreq([mscorlib]System.Runtime.CompilerServices.IsConst) CL1::get_P()
      .set instance void CL1::set_P(int32)
    } 

} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Property P As Integer Implements CL1.P
        Get
            Return Nothing
        End Get
        Set
        End Set
    End Property
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseEmitDiagnostics(
<expected>
BC30657: 'P' has a return type that is not supported or parameter types that are not supported.
        Get
        ~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_08()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{

    .method public hidebysig specialname newslot abstract virtual 
        instance void add_E (
            class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst) 'value'
        ) cil managed 
    {
    }

    .method public hidebysig specialname newslot abstract virtual 
        instance void remove_E (
            class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst) 'value'
        ) cil managed 
    {
    }

    .event [mscorlib]System.Action E
    {
        .addon instance void CL1::add_E(class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst))
        .removeon instance void CL1::remove_E(class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst))
    }
} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Custom Event E As System.Action Implements CL1.E
        AddHandler(d As System.Action)
        End AddHandler
        RemoveHandler(d As System.Action)
        End RemoveHandler
        RaiseEvent
        End RaiseEvent
    End Event
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'E' has a return type that is not supported or parameter types that are not supported.
        AddHandler(d As System.Action)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
BC30657: 'E' has a return type that is not supported or parameter types that are not supported.
        RemoveHandler(d As System.Action)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_09()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{

    .method public hidebysig specialname newslot abstract virtual 
        instance void add_E (
            class [mscorlib]System.Action 'value'
        ) cil managed 
    {
    }

    .method public hidebysig specialname newslot abstract virtual 
        instance void remove_E (
            class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst) 'value'
        ) cil managed 
    {
    }

    .event [mscorlib]System.Action E
    {
        .addon instance void CL1::add_E(class [mscorlib]System.Action)
        .removeon instance void CL1::remove_E(class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst))
    }
} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Custom Event E As System.Action Implements CL1.E
        AddHandler(d As System.Action)
        End AddHandler
        RemoveHandler(d As System.Action)
        End RemoveHandler
        RaiseEvent
        End RaiseEvent
    End Event
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'E' has a return type that is not supported or parameter types that are not supported.
        RemoveHandler(d As System.Action)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
</expected>)
        End Sub

        <Fact()>
        <WorkItem(50327, "https://github.com/dotnet/roslyn/issues/50327")>
        Public Sub ImplementWithModreq_10()
            Dim ilSource = <![CDATA[
.class interface public abstract auto ansi CL1
{

    .method public hidebysig specialname newslot abstract virtual 
        instance void add_E (
            class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst) 'value'
        ) cil managed 
    {
    }

    .method public hidebysig specialname newslot abstract virtual 
        instance void remove_E (
            class [mscorlib]System.Action 'value'
        ) cil managed 
    {
    }

    .event [mscorlib]System.Action E
    {
        .addon instance void CL1::add_E(class [mscorlib]System.Action modreq([mscorlib]System.Runtime.CompilerServices.IsConst))
        .removeon instance void CL1::remove_E(class [mscorlib]System.Action)
    }
} // end of class CL1
]]>.Value

            Dim vbSource =
                <compilation>
                    <file name="c.vb"><![CDATA[
Class Test
    Implements CL1

    Custom Event E As System.Action Implements CL1.E
        AddHandler(d As System.Action)
        End AddHandler
        RemoveHandler(d As System.Action)
        End RemoveHandler
        RaiseEvent
        End RaiseEvent
    End Event
End Class
]]>
                    </file>
                </compilation>

            Dim compilation = CreateCompilationWithCustomILSource(vbSource, ilSource, options:=TestOptions.ReleaseDll)

            compilation.AssertTheseDiagnostics(
<expected>
BC30657: 'E' has a return type that is not supported or parameter types that are not supported.
        AddHandler(d As System.Action)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
</expected>)
        End Sub
    End Class
End Namespace