Improve diagnostics experience for public signing.

- VB: Report a warning about AssemblyKeyFile and AssemblyKeyName attributes being ignored by public signing.
- Disallow public signing for Net modules. The fact that the signing is public is not preserved in a module. The fact of signing is preserved by emitting attributes that are going to be ignored anyway if public signing is used.

Closes #11427.

src/Compilers/CSharp/Portable/CSharpResources.Designer.cs

@@ -7702,6 +7702,15 @@ internal class CSharpResources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Public signing is not supported for netmodules..
+        /// </summary>
+        internal static string ERR_PublicSignNetModule {
+            get {
+                return ResourceManager.GetString("ERR_PublicSignNetModule", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to The range variable &apos;{0}&apos; has already been declared.
         /// </summary>

src/Compilers/CSharp/Portable/CSharpResources.resx

@@ -3833,6 +3833,9 @@ You should consider suppressing the warning only if you're sure that you don't w
   <data name="ERR_PublicSignButNoKey" xml:space="preserve">
     <value>Public signing was specified and requires a public key, but no public key was specified.</value>
   </data>
+  <data name="ERR_PublicSignNetModule" xml:space="preserve">
+    <value>Public signing is not supported for netmodules.</value>
+  </data>
   <data name="WRN_DelaySignButNoKey" xml:space="preserve">
     <value>Delay signing was specified and requires a public key, but no public key was specified</value>
   </data>

src/Compilers/CSharp/Portable/Errors/ErrorCode.cs

@@ -1449,6 +1449,7 @@ internal enum ErrorCode
         ERR_VarInvocationLvalueReserved = 8199,
         ERR_ExpressionVariableInConstructorOrFieldInitializer = 8200,
         ERR_ExpressionVariableInQueryClause = 8201,
+        ERR_PublicSignNetModule = 8202,
         #endregion more stragglers for C# 7
     }
 }

src/Compilers/CSharp/Portable/Symbols/Source/SourceAssemblySymbol.cs

@@ -573,9 +573,16 @@ private void ValidateAttributeSemantics(DiagnosticBag diagnostics)
                 diagnostics.Add(ErrorCode.WRN_DelaySignButNoKey, NoLocation.Singleton);
             }
 
-            if (DeclaringCompilation.Options.PublicSign && !Identity.HasPublicKey)
+            if (DeclaringCompilation.Options.PublicSign)
             {
-                diagnostics.Add(ErrorCode.ERR_PublicSignButNoKey, NoLocation.Singleton);
+                if (_compilation.Options.OutputKind.IsNetModule())
+                {
+                    diagnostics.Add(ErrorCode.ERR_PublicSignNetModule, NoLocation.Singleton);
+                }
+                else if (!Identity.HasPublicKey)
+                {
+                    diagnostics.Add(ErrorCode.ERR_PublicSignButNoKey, NoLocation.Singleton);
+                }
             }
 
             // If the options and attributes applied on the compilation imply real signing,
@@ -790,7 +797,9 @@ private void DetectAttributeAndOptionConflicts(DiagnosticBag diagnostics)
                 }
             }
 
-            if (_compilation.Options.PublicSign && (object)this.AssemblyKeyContainerAttributeSetting != (object)CommonAssemblyWellKnownAttributeData.StringMissingValue)
+            if (_compilation.Options.PublicSign && 
+                !_compilation.Options.OutputKind.IsNetModule() &&
+                (object)this.AssemblyKeyContainerAttributeSetting != (object)CommonAssemblyWellKnownAttributeData.StringMissingValue)
             {
                 diagnostics.Add(ErrorCode.WRN_AttributeIgnoredWhenPublicSigning, NoLocation.Singleton, AttributeDescription.AssemblyKeyNameAttribute.FullName);
             }
@@ -825,7 +834,9 @@ private void DetectAttributeAndOptionConflicts(DiagnosticBag diagnostics)
                 }
             }
 
-            if (_compilation.Options.PublicSign && (object)this.AssemblyKeyFileAttributeSetting != (object)CommonAssemblyWellKnownAttributeData.StringMissingValue)
+            if (_compilation.Options.PublicSign &&
+                !_compilation.Options.OutputKind.IsNetModule() &&
+                (object)this.AssemblyKeyFileAttributeSetting != (object)CommonAssemblyWellKnownAttributeData.StringMissingValue)
             {
                 diagnostics.Add(ErrorCode.WRN_AttributeIgnoredWhenPublicSigning, NoLocation.Singleton, AttributeDescription.AssemblyKeyFileAttribute.FullName);
             }

src/Compilers/CSharp/Test/Emit/Attributes/InternalsVisibleToAndStrongNameTests.cs

@@ -423,6 +423,36 @@ public class C {}
             Assert.True(identity.HasPublicKey);
             AssertEx.Equal(identity.PublicKey, s_publicKey);
             Assert.Equal(CorFlags.ILOnly | CorFlags.StrongNameSigned, metadata.Module.PEReaderOpt.PEHeaders.CorHeader.Flags);
+
+            c = CreateCompilationWithMscorlib(source, options: TestOptions.ReleaseModule.WithCryptoPublicKey(s_publicKey).WithPublicSign(true));
+
+            c.VerifyDiagnostics(
+                // error CS8201: Public signing is not supported for netmodules.
+                Diagnostic(ErrorCode.ERR_PublicSignNetModule).WithLocation(1, 1)
+            );
+
+            c = CreateCompilationWithMscorlib(source, options: TestOptions.ReleaseModule.WithCryptoKeyFile(s_publicKeyFile).WithPublicSign(true));
+
+            c.VerifyDiagnostics(
+                // error CS7091: Attribute 'System.Reflection.AssemblyKeyFileAttribute' given in a source file conflicts with option 'CryptoKeyFile'.
+                Diagnostic(ErrorCode.ERR_CmdOptionConflictsSource).WithArguments("System.Reflection.AssemblyKeyFileAttribute", "CryptoKeyFile").WithLocation(1, 1),
+                // error CS8201: Public signing is not supported for netmodules.
+                Diagnostic(ErrorCode.ERR_PublicSignNetModule).WithLocation(1, 1)
+            );
+
+            var snk = Temp.CreateFile().WriteAllBytes(TestResources.General.snKey);
+
+            string source1 = @"
+[assembly: System.Reflection.AssemblyKeyName(""roslynTestContainer"")] 
+[assembly: System.Reflection.AssemblyKeyFile(@""" + snk.Path + @""")] 
+public class C {}
+";
+
+            c = CreateCompilationWithMscorlib(source1, options: TestOptions.ReleaseModule.WithCryptoKeyFile(snk.Path).WithPublicSign(true));
+            c.VerifyDiagnostics(
+                // error CS8201: Public signing is not supported for netmodules.
+                Diagnostic(ErrorCode.ERR_PublicSignNetModule).WithLocation(1, 1)
+            );
         }
 
         [Fact, WorkItem(9150, "https://github.com/dotnet/roslyn/issues/9150")]

src/Compilers/VisualBasic/Portable/Errors/Errors.vb

@@ -1721,6 +1721,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
 
         ERR_NewWithTupleTypeSyntax = 37280
         ERR_PredefinedValueTupleTypeMustBeStruct = 37281
+        ERR_PublicSignNetModule = 37282
 
         '// WARNINGS BEGIN HERE
         WRN_UseOfObsoleteSymbol2 = 40000
@@ -1941,7 +1942,9 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
         WRN_NoAnalyzerInAssembly = 42377
         WRN_UnableToLoadAnalyzer = 42378
 
-        ' // AVAILABLE                             42379 - 49998
+        WRN_AttributeIgnoredWhenPublicSigning = 42379
+
+        ' // AVAILABLE                             42380 - 49998
         ERRWRN_Last = WRN_UnableToLoadAnalyzer + 1
 
         '// HIDDENS AND INFOS BEGIN HERE

src/Compilers/VisualBasic/Portable/Symbols/Source/SourceAssemblySymbol.vb

@@ -1193,8 +1193,12 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Symbols
                     diagnostics.Add(ERRID.WRN_DelaySignButNoKey, NoLocation.Singleton)
                 End If
 
-                If DeclaringCompilation.Options.PublicSign AndAlso Not Identity.HasPublicKey Then
-                    diagnostics.Add(ERRID.ERR_PublicSignNoKey, NoLocation.Singleton)
+                If DeclaringCompilation.Options.PublicSign Then
+                    If DeclaringCompilation.Options.OutputKind.IsNetModule() Then
+                        diagnostics.Add(ERRID.ERR_PublicSignNetModule, NoLocation.Singleton)
+                    ElseIf Not Identity.HasPublicKey Then
+                        diagnostics.Add(ERRID.ERR_PublicSignNoKey, NoLocation.Singleton)
+                    End If
                 End If
 
                 ' If the options and attributes applied on the compilation imply real signing,
@@ -1274,6 +1278,14 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Symbols
                         diagnostics.Add(ERRID.ERR_CmdOptionConflictsSource, NoLocation.Singleton, AttributeDescription.AssemblyKeyFileAttribute.FullName, "CryptoKeyFile")
                     End If
                 End If
+            ElseIf _compilation.Options.PublicSign Then
+                If Me.AssemblyKeyContainerAttributeSetting IsNot CommonAssemblyWellKnownAttributeData.StringMissingValue Then
+                    diagnostics.Add(ERRID.WRN_AttributeIgnoredWhenPublicSigning, NoLocation.Singleton, AttributeDescription.AssemblyKeyNameAttribute.FullName)
+                End If
+
+                If Me.AssemblyKeyFileAttributeSetting IsNot CommonAssemblyWellKnownAttributeData.StringMissingValue Then
+                    diagnostics.Add(ERRID.WRN_AttributeIgnoredWhenPublicSigning, NoLocation.Singleton, AttributeDescription.AssemblyKeyFileAttribute.FullName)
+                End If
             End If
         End Sub
 

src/Compilers/VisualBasic/Portable/VBResources.Designer.vb

@@ -9324,6 +9324,15 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
             End Get
         End Property
         
+        '''<summary>
+        '''  Looks up a localized string similar to Public signing is not supported for netmodules..
+        '''</summary>
+        Friend ReadOnly Property ERR_PublicSignNetModule() As String
+            Get
+                Return ResourceManager.GetString("ERR_PublicSignNetModule", resourceCulture)
+            End Get
+        End Property
+        
         '''<summary>
         '''  Looks up a localized string similar to Public sign was specified and requires a public key, but no public key was specified.
         '''</summary>
@@ -12675,6 +12684,24 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
             End Get
         End Property
         
+        '''<summary>
+        '''  Looks up a localized string similar to Attribute &apos;{0}&apos; is ignored when public signing is specified..
+        '''</summary>
+        Friend ReadOnly Property WRN_AttributeIgnoredWhenPublicSigning() As String
+            Get
+                Return ResourceManager.GetString("WRN_AttributeIgnoredWhenPublicSigning", resourceCulture)
+            End Get
+        End Property
+        
+        '''<summary>
+        '''  Looks up a localized string similar to Attribute is ignored when public signing is specified..
+        '''</summary>
+        Friend ReadOnly Property WRN_AttributeIgnoredWhenPublicSigning_Title() As String
+            Get
+                Return ResourceManager.GetString("WRN_AttributeIgnoredWhenPublicSigning_Title", resourceCulture)
+            End Get
+        End Property
+        
         '''<summary>
         '''  Looks up a localized string similar to Bad checksum value, non hex digits or odd number of hex digits..
         '''</summary>

src/Compilers/VisualBasic/Portable/VBResources.resx

@@ -4340,6 +4340,15 @@
   <data name="ERR_PublicSignNoKey" xml:space="preserve">
     <value>Public sign was specified and requires a public key, but no public key was specified</value>
   </data>
+  <data name="ERR_PublicSignNetModule" xml:space="preserve">
+    <value>Public signing is not supported for netmodules.</value>
+  </data>
+  <data name="WRN_AttributeIgnoredWhenPublicSigning" xml:space="preserve">
+    <value>Attribute '{0}' is ignored when public signing is specified.</value>
+  </data>
+  <data name="WRN_AttributeIgnoredWhenPublicSigning_Title" xml:space="preserve">
+    <value>Attribute is ignored when public signing is specified.</value>
+  </data>
   <data name="WRN_DelaySignButNoKey" xml:space="preserve">
     <value>Delay signing was specified and requires a public key, but no public key was specified.</value>
   </data>

src/Compilers/VisualBasic/Test/Emit/Attributes/InternalsVisibleToAndStrongNameTests.vb

@@ -337,7 +337,8 @@ End Class
     End Sub
 
     <Fact>
-    Public Sub PublicKeyFromOptions_OssSigned()
+    <WorkItem(11427, "https://github.com/dotnet/roslyn/issues/11427")>
+    Public Sub PublicKeyFromOptions_PublicSign()
         ' attributes are ignored
         Dim source =
 <compilation>
@@ -350,8 +351,13 @@ End Class
     </file>
 </compilation>
 
-        Dim c = CreateCompilationWithMscorlib(source, options:=TestOptions.ReleaseDll.WithCryptoPublicKey(s_publicKey))
-        c.VerifyDiagnostics()
+        Dim c = CreateCompilationWithMscorlib(source, options:=TestOptions.ReleaseDll.WithCryptoPublicKey(s_publicKey).WithPublicSign(True))
+        c.AssertTheseDiagnostics(
+            <expected>
+BC42379: Attribute 'System.Reflection.AssemblyKeyFileAttribute' is ignored when public signing is specified.
+BC42379: Attribute 'System.Reflection.AssemblyKeyNameAttribute' is ignored when public signing is specified.
+            </expected>
+            )
         Assert.True(ByteSequenceComparer.Equals(s_publicKey, c.Assembly.Identity.PublicKey))
 
         Dim Metadata = ModuleMetadata.CreateFromImage(c.EmitToArray())
@@ -360,6 +366,41 @@ End Class
         Assert.True(identity.HasPublicKey)
         AssertEx.Equal(identity.PublicKey, s_publicKey)
         Assert.Equal(CorFlags.ILOnly Or CorFlags.StrongNameSigned, Metadata.Module.PEReaderOpt.PEHeaders.CorHeader.Flags)
+
+        c = CreateCompilationWithMscorlib(source, options:=TestOptions.ReleaseModule.WithCryptoPublicKey(s_publicKey).WithPublicSign(True))
+        c.AssertTheseDiagnostics(
+            <expected>
+BC37282: Public signing is not supported for netmodules.
+            </expected>
+            )
+
+        c = CreateCompilationWithMscorlib(source, options:=TestOptions.ReleaseModule.WithCryptoKeyFile(s_publicKeyFile).WithPublicSign(True))
+        c.AssertTheseDiagnostics(
+            <expected>
+BC37207: Attribute 'System.Reflection.AssemblyKeyFileAttribute' given in a source file conflicts with option 'CryptoKeyFile'.
+BC37282: Public signing is not supported for netmodules.
+            </expected>
+            )
+
+        Dim snk = Temp.CreateFile().WriteAllBytes(TestResources.General.snKey)
+
+        Dim source1 =
+<compilation>
+    <file name="a.vb"><![CDATA[
+<assembly: System.Reflection.AssemblyKeyName("roslynTestContainer")>
+<assembly: System.Reflection.AssemblyKeyFile("]]><%= snk.Path %><![CDATA[")>
+Public Class C
+End Class
+]]>
+    </file>
+</compilation>
+
+        c = CreateCompilationWithMscorlib(source1, options:=TestOptions.ReleaseModule.WithCryptoKeyFile(snk.Path).WithPublicSign(True))
+        c.AssertTheseDiagnostics(
+            <expected>
+BC37282: Public signing is not supported for netmodules.
+            </expected>
+            )
     End Sub
 
     <Fact>
@@ -1706,14 +1747,17 @@ End Class
         PublicSignCore(compilation)
     End Sub
 
-    Public Sub PublicSignCore(compilation As Compilation)
+    Public Sub PublicSignCore(compilation As Compilation, Optional assertNoDiagnostics As Boolean = True)
         Assert.True(compilation.Options.PublicSign)
         Assert.Null(compilation.Options.DelaySign)
 
         Dim stream As New MemoryStream()
         Dim emitResult = compilation.Emit(stream)
         Assert.True(emitResult.Success)
-        Assert.True(emitResult.Diagnostics.IsEmpty)
+        If assertNoDiagnostics Then
+            Assert.True(emitResult.Diagnostics.IsEmpty)
+        End If
+
         stream.Position = 0
 
         Using reader As New PEReader(stream)
@@ -1759,6 +1803,7 @@ End Class
         AssertTheseDiagnostics(c,
                                <errors>
 BC37254: Public sign was specified and requires a public key, but no public key was specified
+BC42379: Attribute 'System.Reflection.AssemblyKeyFileAttribute' is ignored when public signing is specified.
                                </errors>)
 
         Assert.True(c.Options.PublicSign)
@@ -1778,6 +1823,7 @@ End Class
         AssertTheseDiagnostics(c,
                                <errors>
 BC37254: Public sign was specified and requires a public key, but no public key was specified
+BC42379: Attribute 'System.Reflection.AssemblyKeyNameAttribute' is ignored when public signing is specified.
                                </errors>)
 
         Assert.True(c.Options.PublicSign)
@@ -1845,7 +1891,14 @@ End Class
         Dim snk = Temp.CreateFile().WriteAllBytes(TestResources.General.snKey)
         Dim options = TestOptions.ReleaseDll.WithCryptoKeyFile(snk.Path).WithPublicSign(True)
         Dim compilation = CreateCompilationWithMscorlib(source, options:=options)
-        PublicSignCore(compilation)
+
+        AssertTheseDiagnostics(compilation,
+                               <errors>
+BC42379: Attribute 'System.Reflection.AssemblyKeyFileAttribute' is ignored when public signing is specified.
+BC42379: Attribute 'System.Reflection.AssemblyKeyNameAttribute' is ignored when public signing is specified.
+                               </errors>)
+
+        PublicSignCore(compilation, assertNoDiagnostics:=False)
     End Sub
 
     <Fact>