generate binary literals for enums that are already binary (#13376)

* generate binary literals for enums that are already binary

* adds test for binary enum int-max

src/EditorFeatures/CSharpTest/Diagnostics/GenerateEnumMember/GenerateEnumMemberTests.cs

@@ -129,6 +129,14 @@ public async Task TestWithDifferentStyles()
 @"class Program { void Main ( ) { Color . Blue ; } } enum Color { Red = 2 , Green = 1 << 5 , Blue = 33 } ");
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateEnumMember)]
+        public async Task TestBinary()
+        {
+            await TestAsync(
+@"class Program { void Main ( ) { Color . [|Blue|] ; } } enum Color { Red = 0b01 } ",
+@"class Program { void Main ( ) { Color . Blue ; } } enum Color { Red = 0b01 , Blue = 0b10 } ");
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateEnumMember)]
         public async Task TestHex1()
         {
@@ -177,6 +185,14 @@ public async Task TestGenerateEnumMemberOfTypeLong()
 @"class Program { void Main ( ) { Color . Blue ; } } enum Color : long { Red = long.MaxValue , Blue = long.MinValue } ");
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateEnumMember)]
+        public async Task TestGenerateAfterEnumWithLongMaxValueInBinary()
+        {
+            await TestAsync(
+@"class Program { void Main ( ) { Color . [|Blue|] ; } } enum Color : long { Red = 0b0111111111111111111111111111111111111111111111111111111111111111 } ",
+@"class Program { void Main ( ) { Color . Blue ; } } enum Color : long { Red = 0b0111111111111111111111111111111111111111111111111111111111111111 , Blue = 0b1000000000000000000000000000000000000000000000000000000000000000 } ");
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateEnumMember)]
         public async Task TestGenerateAfterEnumWithLongMaxValueInHex()
         {

src/EditorFeatures/VisualBasicTest/Diagnostics/GenerateEnumMember/GenerateEnumMemberTests.vb

@@ -34,6 +34,13 @@ NewLines("Module Program \n Sub Main(args As String()) \n Foo([|Color.Green|]) \
 NewLines("Module Program \n Sub Main(args As String()) \n Foo(Color.Green) \n End Sub \n End Module \n Enum Color \n Red = 1 \n Green = 2 \n End Enum"))
         End Function
 
+        <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateEnumMember)>
+        Public Async Function TestGenerateBinaryLiteral() As Task
+            Await TestAsync(
+NewLines("Module Program \n Sub Main(args As String()) \n Foo([|Color.Green|]) \n End Sub \n End Module \n Enum Color \n Red = &B01 \n End Enum"),
+NewLines("Module Program \n Sub Main(args As String()) \n Foo(Color.Green) \n End Sub \n End Module \n Enum Color \n Red = &B01 \n Green = &B10 \n End Enum"))
+        End Function
+
         <Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateEnumMember)>
         Public Async Function TestGenerateIntoLinearIncreasingSequence() As Task
             Await TestAsync(

src/Workspaces/CSharp/Portable/CodeGeneration/EnumMemberGenerator.cs

@@ -139,6 +139,11 @@ private static ExpressionSyntax CreateEnumMemberValue(EnumDeclarationSyntax dest
                                 return SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression,
                                     SyntaxFactory.Literal(numericText.Substring(0, 2) + value.ToString("X"), value));
                             }
+                            else if (numericText.StartsWith("0b", StringComparison.OrdinalIgnoreCase))
+                            {
+                                return SyntaxFactory.LiteralExpression(SyntaxKind.NumericLiteralExpression,
+                                    SyntaxFactory.Literal(numericText.Substring(0, 2) + Convert.ToString(value, 2), value));
+                            }
                         }
                     }
                 }

src/Workspaces/VisualBasic/Portable/CodeGeneration/EnumMemberGenerator.vb

@@ -121,6 +121,8 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.CodeGeneration
                                 End If
                             ElseIf numericText.StartsWith("&O", StringComparison.OrdinalIgnoreCase) Then
                                 Return SyntaxFactory.NumericLiteralExpression(SyntaxFactory.IntegerLiteralToken(numericText.Substring(0, 2) + Convert.ToString(value, 8), LiteralBase.Octal, TypeCharacter.None, IntegerUtilities.ToUnsigned(value)))
+                            ElseIf numericText.StartsWith("&B", StringComparison.OrdinalIgnoreCase) Then
+                                Return SyntaxFactory.NumericLiteralExpression(SyntaxFactory.IntegerLiteralToken(numericText.Substring(0, 2) + Convert.ToString(value, 2), LiteralBase.Binary, TypeCharacter.None, IntegerUtilities.ToUnsigned(value)))
                             End If
                         End If
                     End If